tag:blogger.com,1999:blog-75808943489011059042024-03-18T02:48:46.948-07:00Safe FoodI am a professional food microbiologist. I created this blog to help ordinary folk and food manufacturers understand food safety so that we can reduce the incidence of food mediated illness. I would like it to become a resource for teachers in schools.
If readers send comments or questions, I'll try to incorporate them into future postings. Write to: FoodMicrobiologist.007@gmail.com
I hope you find the site useful and perhaps even thought-provoking.John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.comBlogger202125tag:blogger.com,1999:blog-7580894348901105904.post-44407437440446155132023-07-21T22:42:00.002-07:002023-07-21T22:42:56.957-07:00More on antibiotic resistant bacteria in natural waters and wild-harvested foods.<p>I wrote an article on 05/12/2012 about our isolation of antibiotic-resistant genes in bacteria in water and in stream and river muds, comparing pristine waters with polluted ones along a stretch of a river in the Waikato region of New Zealand.</p><p>I recently read another article by Jack Heinemann and Sophie Joy van Hamelsveld from University of Canterbury in Stuff: https://www.stuff.co.nz/pou-tiaki/300930926/antibioticresistant-bacteria-in-wild-cockles-and-watercress-putting-people-at-risk-of-serious-illness. It's worth a read.</p><div><br /></div><div>The article raises yet another concern about antibiotic resistance. The testing of water for recreational use does not guarantee that mahinga kai, wild-harvested foods, such as shellfish, are safe to eat. Shellfish can concentrate bacteria from the water to high levels, even when the tested water appears to be safe.</div>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-46415253335206576642023-02-15T23:51:00.001-08:002023-02-16T00:01:27.796-08:00Is the food still safe to eat?<p> For the past few days, New Zealand has suffered from high winds and extensive flooding as a result of Cyclone Gabrielle, which in some coastal areas has coincided with high tides. Many areas have been without power for extended periods and thousands of people have had to leave their homes, in some cases being rescued from the roofs of their houses.</p><p>I was interviewed by a radio journalist who wanted to ask questions about the safety of food and water. Any food that has been contaminated by the flood waters is, of course, not fit to eat. But what of foods that were in refrigerators and freezers?</p><p>This is a difficult question to answer. If the power has been off for a few hours and the refrigerator has not been opened, the food will probably be safe to eat, however, some areas are not likely to have power restored for several days. Some foods, such as yoghurt are naturally preserved by their acid content and will be shelf-stable even at room temperature for a few days. Hard cheeses will also be safe. Similarly, milk in sealed bottles will be OK for a couple of days. Vegetables are also shelf-stable for several days at room temperature, provided that they have not been in the water. Eggs have their shells to protect the contents, but it would be worth washing the shells to prevent contamination of the contents when they are cracked open. Perhaps a good guide is to think of supermarket displays - if the food such as fruit, potatoes, tomatoes and cabbages is sold from open counters, it can reasonably be expected to last for several days.</p><p>The big concern will be fish and meat. If the frozen food has thawed out completely, it may still be safe to eat if it is thoroughly cooked. if the food still has ice crystals in it, refreezing is possible. Beef and pork steaks are essentially sterile inside, so it is only necessary to cook the outside, remembering to cook the edges too. Fish is normally sold in fillets, so again, frying or barbecuing will render it safe, however, the food cannot be stored for another few days before consumption. I would be more concerned about chicken, which is always difficult to cook throughout because of the uneven thickness of drumsticks etc. In all cases, the critical thing is to get the temperature of the food above about 75C throughout. This will kill all vegetative (non-sporulated) bacterial cells. If a thermometer is used, it must be clean and inserted into the thickest part of the food. More care is required with minced meat. During the mincing operation, the outside of the meat is mixed in with the interior portions, so thorough cooking is required - medium-rare hamburgers are out! </p><p>Another, though not infallible guide is to look at the food and smell it - if it smells off, then don't eat it. Things like bacon sometimes become a bit slimy as a result of bacterial growth on the surface. If it is fried properly, it will be safe to eat, but may have off-flavours.</p><p>Of course, canned foods are safe, provided that there are no holes in the can. Similarly, sealed packages of snack foods, such as 'chippies' will be OK to eat and may make the kids feel a bit happier. It is a good idea always to have a supply of canned foods in the cupboard so that they are available in emergency situations like ours.</p><p>Another major concern is water. Some water treatment plants have been out of action for a couple of days as a result of power outages and some watersheds may have been swamped by flood waters. A number of water supply authorities have said that the tap water is safe to drink. However, if there is any doubt about its safety, it should be boiled. I was asked about water for making up baby formula. In that situation, I would always recommend using boiled water. Rural households often collect water from the house roof and store it in large tanks. In my opinion, this water will be safe, provided that the roof and tanks have not been inundated, but once again, if there is any doubt and the power is on, it should be boiled.</p><p>All of these questions will become more relevant when people are allowed to return to their dwellings. There may be a temptation to try to salvage food from refrigerators and cupboards. If there is any doubt, the safest thing to do is to dump it, as food poisoning will put even more stress on health services at this time.</p><p>Our next concern will be resupply. Many roads are impassable, leaving some towns completely cut off. Supermarkets are very short on stock, even if they have power to operate the tills. Foods may be in short supply for a while, but in addition, orchards and vegetable farms have been severely damaged, so shortages will continue for months. There may be more reliance on imports.</p><p>Odd Spot: if the cyclone were not enough to challenge the population, we also had a magnitude 6.3 earthquake yesterday. It was centred about 50km NE of Paraparaumu in the North Island, so it was under the sea. There have been no reports of injuries or damage, but it's something we could all have done without!</p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-82248387007394815352022-06-10T16:30:00.001-07:002022-06-10T16:41:31.476-07:00Will in vitro meat be the new SCP?<p> <span style="font-family: "Helvetica Neue"; font-size: 11px;">In the 1960s, several companies began development of Single Cell Protein (SCP) as a protein source for human and animal feed.</span><span style="font-family: "Helvetica Neue"; font-size: 11px;"> </span><span style="font-family: "Helvetica Neue"; font-size: 11px;">SCP refers to protein produced by microorganisms, such as bacteria, yeasts and unicellular algae.</span><span style="font-family: "Helvetica Neue"; font-size: 11px;"> </span><span style="font-family: "Helvetica Neue"; font-size: 11px;">This was not a new concept and can be traced back at least as far as 1936.</span></p>
<p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;">My first job was as a fermentation experimental officer at ICI in the UK, helping to develop the ICI Single Cell Protein Process. Several other companies were developing SCP for human and animal consumption. ICI intended to produce 1m te/yr by the 1990s; Shell was working on producing SCP as a by-product of gas oil dewaxing. Several other processes were based on mycoprotein from Fusarium <i>sp.- </i>‘Quorn’, and algae. These projects involved very significant effort and investment; it has been estimated that by 1983, the main players had invested in R&D a staggering $US 2.9 x 10<span style="font-size: 7.3px; font-stretch: normal; line-height: normal;"><sup>8</sup></span> in today’s terms.</p><p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;"><br /></p>
<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIywdX_CnEgV6EiExpR0BiDPmEpk1xppxn3FahaTZjOk5AXnkTz-2WQYwN4p9jV24Wj8YFEtfZS_A7X3U_a7G5p47mQ1YyFThyt4NfX5eNYZhUJZO2AFts4t9R0o_wstIY0-mOPkLTu1cdtqkY7N6CZksYryo5qn8_EqlUUb21Z7sx4iWQHBU_cx8oNA/s1226/Screen%20Shot%202022-06-11%20at%2011.14.03.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1226" data-original-width="818" height="259" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIywdX_CnEgV6EiExpR0BiDPmEpk1xppxn3FahaTZjOk5AXnkTz-2WQYwN4p9jV24Wj8YFEtfZS_A7X3U_a7G5p47mQ1YyFThyt4NfX5eNYZhUJZO2AFts4t9R0o_wstIY0-mOPkLTu1cdtqkY7N6CZksYryo5qn8_EqlUUb21Z7sx4iWQHBU_cx8oNA/w173-h259/Screen%20Shot%202022-06-11%20at%2011.14.03.png" width="173" /></a></div><blockquote style="border: none; margin: 0px 0px 0px 40px; padding: 0px; text-align: left;"><p style="text-align: center;"><span style="font-size: x-small;"><span style="font-weight: normal;">Image shows the ICI production fermenter for SCP. </span>60m tall with a capacity of <span style="font-family: "Helvetica Neue";">3,000m</span><span style="font-family: "Helvetica Neue"; font-stretch: normal; line-height: normal;"><sup>3</sup></span>. <span style="font-family: "Helvetica Neue"; font-stretch: normal; line-height: normal;"><sup> </sup></span> </span><i><span style="font-size: x-small;">I do not own the copyright of this image.</span></i></p></blockquote>
<p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;">The new processes were beset with problems. Bacterial cells contain relatively large amounts of RNA, which can result in gout and kidney stones in consumers, as purines increase plasma uric acid, so RNA reduction was required. Some products had undesirable taste, and considerable downstream processing was required to produce acceptable texture and mouthfeel. Consumer acceptance of food made from bacteria was also difficult to achieve. However, one of the greatest hurdles was the scale of operation required and the resulting cost of the product. Most of these processes, while being technological marvels, were not commercially successful. In fact, as far as I am aware, the only product now on the market is Quorn.</p>
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<p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;">Against this background, we see <i>in vitro </i>meat (IVM) or cultured meat, being developed as a sustainable food. It is also referred to as ‘Lab-grown meat’, illustrated by lumps of tissue apparently grown in Petri dishes, though this is perhaps somewhat misleading, as the scale of operation to produce sufficient product to be economically viable would require a facility similar in size to a modern dairy plant.<b> </b>To produce IVM, stem cells are collected from living animals and cultured in a reactor, using suitable culture media, which must be made up of food-grade components. Typically, vitamins, antibiotics, growth factors, such as calf serum, horse serum and chicken embryo extract are included, (though I have seen a recent report stating that calf serum is not necessary). The stem cells will differentiate into muscle cells under the influence of certain hormones. Obviously, strict sterility must be maintained, or contaminating bacteria will grow in the highly nutritious medium. The developing cells will require a supply of oxygen, carbon dioxide will be produced in the metabolic processes, and heat will have to be removed.</p>
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<p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;">Merely getting the muscle cells to grow is only part of the process - Since consumers want something that resembles meat as closely as possible, some form of three-dimensional scaffolding is usually required for the cells to fuse together to form organised tissues.</p>
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<p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;">For many people, the decision to purchase IVM will come down to taste, texture, appearance and cost. Estimates suggest that IVM will be twice the price of farmed meat. I saw recently a report that a burger pattie could cost around $11.35 I will be happy to eat IVM, but not if the product costs a lot more than my favourite grass-fed beef fillet steak.</p><p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;"><br /></p><p style="font-family: "Helvetica Neue"; font-size: 11px; font-stretch: normal; line-height: normal; margin: 0px;"><br /></p><div><br /></div>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-39709676552314648922021-07-08T19:25:00.000-07:002021-07-08T19:25:05.716-07:00Got the munchies?<p> Hands up anyone who, at any time during their lifetime, has scraped the cake mixing bowl and eaten the residues, or eaten raw cookie dough. Yes, I see a lot of you with your hands up! In a survey by Ardent Mills, Minnesota, 73% of respondents admitted to eating raw homemade cookie dough and 57% allowed children to lick the bowl and spoon after mixing cakes, while 65% admitted to eating store-bought cookie dough without cooking. In a 2009 outbreak of Escherichia coli O157 food poisoning in 30 U.S. states, 77 patients, mostly young females contracted the illness and 35 were hospitalised. A common factor revealed in the investigation was consumption of commercial raw cookie dough produced in a single plant. As a result, 3.6 million packages of ready-to-bake cookie dough were recalled.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-0BzA8vIFeHQ/YOeyLdaXeyI/AAAAAAAAJdQ/QKc_3ZENDXk2o6tNPjqQwFksiYJmzH8sQCLcBGAsYHQ/s1870/Screen%2BShot%2B2021-07-09%2Bat%2B14.18.10.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1252" data-original-width="1870" src="https://1.bp.blogspot.com/-0BzA8vIFeHQ/YOeyLdaXeyI/AAAAAAAAJdQ/QKc_3ZENDXk2o6tNPjqQwFksiYJmzH8sQCLcBGAsYHQ/s320/Screen%2BShot%2B2021-07-09%2Bat%2B14.18.10.png" width="320" /></a><br /></div><p>I used to beg my Mum not to use a spatula to scrape all the mixture from the bowl. Mum didn’t know much about food safety; she had no formal training and over the years had learned how to bake. Many younger people are probably in the same boat. Most of us know that you can possibly pick up Salmonella food poisoning from eating undercooked eggs or chicken, and that the foods likely to give you food poisoning include leafy greens and sprouts, raw shellfish and raw milk, though the latter usually ignites a flame war if you publish comments. <br /><br />So if you are asked why you should not eat raw cookie dough, what will you say is the risk? Salmonella in the uncooked eggs, right? What about the flour? In 2016, ten million pounds of raw flour were recalled owing to contamination with Escherichia coli. That year, the U.S. FDA and Centres for Disease Control and Prevention investigated infections by E.coli O121 occurring across the country. Some serotypes of this bacterium can produce Shiga toxins. A great deal is now known about Shiga toxins, but for our purposes here, we can say that ingestion of the toxin results in abdominal pain and watery diarrhoea, but may also cause haemorrhagic colitis, which is far more serious. <br /><br />The April 23 edition of Morbidity and Mortality Weekly Report discussed multi-state outbreaks of E. coli O26:H11 infections linked to raw flour in 2019. The investigators initially thought that ground beef was the source of the infection - patients interviewed reported eating ground beef and leafy greens. However, by the use of modern microbiological analytical techniques - Pulsed Field Gel Electrophoresis and Core Genome Multilocus Sequence Typing - they were able to show that the STEC O26:H11 isolates were different from those strains that had caused the ground beef illnesses in 2018.<br /><br />How does flour, which is dry and doesn’t support bacterial growth, come to be involved in E. coli food poisoning transmitted in raw cookie dough? Wheat flour is grown outdoors and may be contaminated from soil or birds and animals. Cattle and deer have no cell receptors for Shiga toxin, so may carry the toxigenic bacteria without ill effect. The milling process generally doesn’t include a lethal process step, so E. coli and Salmonella can survive into the finished product. These vegetative cells are killed during cooking, but may be present in raw dough and cake batter.<br /><br />Heat treatment of flour has been used in the past to destroy pathogens, but is expensive and has a negative impact on the properties of gluten, potentially making the flour unsuitable for baking. Various other treatments have been proposed, including cold plasma, electron beam and gamma irradiation, but these methods may meet with consumer resistance.<br /><br />A company based in Ontario, Canada has recently developed an organic, non-thermal treatment for flour that is a liquid added at the tempering stage of milling. However, as far as I am aware, this treatment is not yet used in commercial flour production. <br /><br />What about making home-made raw cookie dough safe? It is extraordinarily difficult to find information on how to pasteurise raw flour at home to make raw cookie dough treats. One blogger has described home pasteurisation of flour, using a 1200 watt microwave oven to heat the flour to 71C with a 55 second treatment. She based this treatment on advice from FDA and I estimate that the flour receives an F0 of around 4. <br /><br />FDA is now pushing the message “Don’t eat any raw cookie dough, cake mix, batter, or any other raw dough or batter product that is supposed to be cooked or baked” and “Follow package directions for cooking products containing flour at proper temperatures and for specified times”.<br />Indeed, some packages of flour in US now have a label warning consumers to “Cook before sneaking a taste”.<br /><br />Still want to risk it?<br /><br /></p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com1tag:blogger.com,1999:blog-7580894348901105904.post-63319550675977647032021-07-08T12:20:00.002-07:002021-07-08T19:25:59.716-07:00Subscriber e-mails discontinued<p> If you have been receiving e-mail notification of new posts on this blog, you need to be aware that <span class="w4txWc oJeWuf" id="c15" role="region">recently, the FeedBurner team released a system update
<a href="https://www.blogger.com/go/follow-by-email-deprecation-annoucement" target="_blank">
announcement
</a>
that the email subscription service will be discontinued in July 2021. </span></p><p><span class="w4txWc oJeWuf" id="c15" role="region"> </span><span class="w4txWc oJeWuf" id="c15" role="region">The blog will still exist and you can search earlier posts, but you will not be notified of new ones.</span></p><p><span class="w4txWc oJeWuf" id="c15" role="region">This is not under my control, but I apologist for any inconvenience or irritation that this causes you. </span></p><p><span class="w4txWc oJeWuf" id="c15" role="region">Please consider bookmarking this blog and check it occasionally <br /></span></p><p><span class="w4txWc oJeWuf" id="c15" role="region">Regards, John<br /></span></p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-57850752919706833002020-11-12T13:21:00.000-08:002020-11-12T13:21:00.702-08:00Hello Fresh fish causes food poisoning in New Zealand<p> At least three people have been treated in hospital for scombroid poisoning after eating Trevally from a meal kit supplied by Hello Fresh.</p><p>Histidine in the fish tissue can be converted to histamine by histidine decarboxylase, found in <i>Escherichia coli, Morganella morganii, </i>Proteus, Pseudomonas and Klebsiella species, which may occur naturally in the gills, skin and gut. If the fish is not properly handled after being caught and during transport and distribution, allowing the temperature to rise for an extended period, these bacteria can grow and produce sufficient histamine to cause an allergic reaction in the consumer. </p><p>Scombroid poisoning was originally named because Scombridae fish naturally contain higher levels of histidine. The range of symptoms varies, but includes nausea, headaches, vomiting and diarrhoea and possibly itching and a burning sensation in the lips.</p><p>Unfortunately, the fish may not appear to be spoiled and the enzyme remains active even after the bacteria have been killed, continuing to produce histamine under cold storage. Activity can resume when frozen fish is thawed. Histamine cannot be destroyed by cooking, so control of storage temperature is essential throughout the food chain.<br /></p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-59469775930451918332020-09-04T22:28:00.001-07:002020-09-06T00:31:29.738-07:00Nothing new under the Sun<p> Sorry! That was a click bait title. However, as far as food poisoning goes, there really is very little that is new - the same old suspects keep turning up.</p><p>I've written about <i>Clostridium botulinum </i>before (and you can find those posts by searching the labels). It has now caused food poisoning in Vietnam, this time in Minh Chay pate products, which have all been recalled. The outbreak is reported in <a href="https://www.foodsafetynews.com/2020/09/botulism-cases-linked-to-pate-in-vietnam/">Food Safety News</a>. The article includes a photograph of the product, which is packed in screw capped jars and possibly cans.</p><p>The Department of Food Safety, Ministry of Health, inspected the premises and found 'sanitary issues' with cleaning and drainage. The factory was instructed to cease production until the problems were fixed.</p><p>There is insufficient information in the article to make definitive pronouncements on the causes of the contamination, but some reasonable arguments can be made. <i>C. botulinum </i>releases a toxin when it sporulates, and for this it must grow. Since the bacterium is anaerobic, it requires the absence of oxygen. It appears, therefore, that the pate was contaminated during manufacture, possibly from the unclean factory environment, and the organism then grew in the sealed containers. The article doesn't state whether the product was hot-filled, or heat processed in the containers. In the former scenario, the spores of <i>C. botulinum </i>could germinate and grow in the product, eventually leading to toxin production. If the containers were heat processed after filling, it is possible that contaminated cooling water leaked into the containers through faulty seams or seals.</p><p>The toxin binds in the nerve synapses and prevents the secretion of acetyl choline, thus preventing nerve impulse transmission. This usually causes respiratory paralysis, so patients need support to breathe.</p><p>Interestingly, if you search for 'Botulin toxin' on-line, the first five hits refer to Botox, the cosmetic treatment to reduce frown lines and crows' feet. Food poisoning is mentioned almost as an afterthought.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-Oo7LtxVtvwk/X1SQJtko37I/AAAAAAAACi4/cECWjL7p_N0IU2NawIbpiDG02BVn60L5QCLcBGAsYHQ/s778/C%2Bbotulinum.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="772" data-original-width="778" src="https://1.bp.blogspot.com/-Oo7LtxVtvwk/X1SQJtko37I/AAAAAAAACi4/cECWjL7p_N0IU2NawIbpiDG02BVn60L5QCLcBGAsYHQ/s320/C%2Bbotulinum.jpeg" width="320" /></a></div>https://microbewiki.kenyon.edu/images/9/95/Screen_Shot_2014-04-21_at_9.23.54_PM.png<br /><p><br /><i></i></p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-71258916851982961882020-08-27T19:03:00.003-07:002021-07-09T12:30:05.919-07:00Infection transmission<p> The COVID-19 pandemic should have got us all thinking about infection transmission and control. Yet, the virus continues to spread.</p><p>I remember the pretty much the first laboratory class we did in Microbiology 101 was a demonstration of how infection transfers within a community. There were 24 students in the class.</p><p>First, everyone wiped their hands with a paper tissue, <b>one</b> of which had been contaminated with a bacterial culture. This organism was <i>Serratia marcescens</i>, which produces a bright red pigment when grown under the right conditions. A sequence grid was set up, so that everyone shook hands with one other class member and then plated their hand onto an agar plate.</p><p>The second round of hand shakes was then undertaken with different class members, without first washing our hands, and, again, hands were plated. This sequence continued until, by the end, everyone had shaken hands with about 10 classmates and plated their hands.</p><p>The plates were incubated, and a couple of days later were examined for the presence of the bright red colonies. Scoring the positives against the sequence grid, it was very obvious how the infection had spread throughout the class. Not everyone became infected initially, but the infection spread exponentially and after six rounds, everyone in the class was positive.</p><p>How is this relevant to COVID-19 spread? This virus is supposedly spread predominantly by droplet inhalation. However, an individual may become infected by touching their face with infected hands or perhaps by rubbing their eyes. The virus, like the <i>Serratia</i>, might be picked up on the hands from surfaces like door handles, wash basin surrounds, pens, or from shaking hands with a carrier etc. "OK, I don't touch my face and eyes". Are you sure? I used to lecture to classes of up to 130 students and occasionally counted how many were touching their face at any one time. (Yes, I know, I had put half of them to sleep and their heads were in their hands). Up to 60% of the class touched their faces and noses and eyes. A similar surreptitious survey found that up to 30% of students left the toilets without washing their hands!</p><p>The take-home message here is - "Wash and sanitise your hands regularly - many times a day; avoid hand shaking and kissing 😞 and if you are sick, STAY HOME. In fact, if you don't <i>have</i> to mix with people, stay away from them." Like in our first year experiment, there was no indication that any particular person was carrying the infection until two days later when the test results were available.</p><p><b>Update: </b>As of today, 10th July 2021, we have seen over 4 million people die of COVID-19 around the world and it is now obvious that the primary route of transmission is by inhalation of virus particles. Mask wearing significantly reduces the spread of the virus by trapping droplets and by wearing a mask, you are protecting others. In countries where people still gather together in crowds, the virus is spreading very fast and the delta variant, which is highly infectious, is ripping through the population.</p><p>If you are reading this update and you have the option, please GET VACCINATED, both for your own safety and the protection of your friends and family.<br /></p>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-4667729660538845062020-07-25T15:45:00.002-07:002020-07-25T16:03:22.027-07:00Should we switch to plant-based proteins?While New Zealand was in lockdown, I had ample opportunity to think about life, the universe and everything. Specifically, I was thinking about plant-based protein as human food. Recently, meals at home have exposed me a variety of new dishes and some of these were plant-based. I’m setting out these thoughts in the hope that they will stimulate conversation between readers.<br /><br />First, there is a strong drive from some members of the community to change from eating animal proteins to eating plant-based protein meals. Some of this is a concern for the welfare of animals and some is ideological. Probably the primary driver is health, but the second driver is sustainability and environmental concerns around our planet and its long term health. Is it really more healthy to eat only plant proteins? Is it truly better for the environment? There is concern that rivers and waterways are being polluted by our raising of animals for meat and milk, but will the production of plant proteins result in greater use of fertiliser and hence increase runoff? Methane emissions will decrease, but growth of legumes may ultimately result in increased nitrate leeching. Of course, traditional farming mixed plants and animals - the vegetables etc. were grown on land fertilised by animal manure, but if we no longer raise animals, that cycle will be eliminated. <br /><br />What is the point of trying to reproduce the taste, appearance and texture of products such as burgers, but using plant proteins? Really, that is just a sop to confirmed meat eaters. As I understand it, The Impossible Burger is more expensive to produce than the meal it is trying to emulate. Is there going to be resistance to the use of colours and flavours to simulate animal products? The key ingredient that gives the Impossible Burger its meaty taste and makes it bleed like meat when cut is soy leghemoglobin, derived from genetically engineered yeast. Production of the yeast by fermentation requires inputs of industrially manufactured, chemically synthesised ingredients. The safety of these inputs will be subject to regulatory approval and their use will not be universally accepted. Ikea is introducing a non-meat version of its traditional Swedish meatball and claims that conversion of about 20 per cent of its meatball sales to plant balls would mean around 8 per cent reduction of the climate footprint for the food business at Ikea. Meanwhile, KFC has announced that it is collaborating with 3-D Bioprinting Solutions to develop chicken nuggets made with cultured chicken cells and plant material. The thinking of food technologists and new product developers is way ahead of the general population.<br /><br />We all require iron in our diets, young or pregnant women particularly. The recommended daily allowance for vegetarians is 1.8 times higher than for people who eat meat. This is because heme iron from meat is more bioavailable than non-heme iron from plant-based foods, and meat, poultry, and seafood increase the absorption of non-heme iron. This is just one aspect of changing from eating animal protein to exclusively plant-based protein. There is any amount of information on the Internet regarding iron requirements and sources, but caution is required before believing everything!<br /><br />I really have no answers for these questions, but I think that the proponents of moving to an exclusive plant protein diet haven’t thought it through. Here are some questions that I’d like answered:<br /><br />Does New Zealand have sufficient agricultural land to produce all the plant protein we need to feed the population, assuming that we all move to consuming it? Much of our farming is on hill country. This is not suitable for crop production.<br /><br />Will the energy inputs for food production increase or decrease? We will need diesel to harvest the crops and energy to dry some of the products. With the shutdown of the Tiwai Point Aluminium smelter, there may be an opportunity to divert some of the surplus electricity to processing of plant proteins, but will that be enough or even practical?<br /><br />What of our exports? In 2019, dairy, eggs and honey earned NZ$16.3 billion and accounted for 27.9% of total exports, while meat earned NZ$8.03 billion - 13.9% of total exports. If meat and dairy were no longer produced here, that would be a loss of nearly 42% of our exports. In the current post COVID-19 era, it would be hard to replace those contributions.<br /><br />John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-48622149822002007032020-04-11T19:40:00.000-07:002020-04-11T19:40:15.909-07:00Safe Food in LockdownAre you tired of reading and hearing about COVID-19 yet? Are you totally confined to your home, or are you an essential service worker? How have things changed for you?<br />
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My on-line news service provides the ten top items each day as links. For the last two weeks, nine out of the ten have been about COVID-19 and mostly they provide depressing reading. I'm not going to rehash all that.<br />
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New Zealand, where I live, has closed its borders. <br />
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The majority of shops are closed, so our food shopping is mostly confined to visits to the supermarket, which may involve long queues and limited numbers of people in the building at any time, so the on-line ordering and collection option is popular. The 2-metre separation rule is now being followed by most people.<br />
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How does this affect our eating habits? Well, restaurants and fast food joints are closed, so we are all preparing many more meals at home from what we have on hand. This may involve substitution of ingredients, or complete change of menu at short notice. Not everyone is used to cooking meals at home and there may be a few disasters! <br />
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Do we need to worry about contracting the virus from our food? The best information I have is that this is a respiratory infection and you can't pick it up from food. Since it is a virus, it can't replicate in stored food, so the only concern is with contamination of the packaging. Survival time on surfaces seems to vary, but studies by CDC, researchers at various universities and FDA indicate that the survival time varies from a few hours to about three days, but it is important to remember that the AMOUNT of virus remaining may be as low as 0.01% of the original contamination. It is unlikely that you can contract the virus from food packaging, but it's a good idea to wipe the packaging down with a 1:48 dilution of household 6% bleach, (5mL 6% bleach into 240mL water) or just leave the packages unopened for a few days.<br />
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So, do we need to change our cooking and eating habits? Essentially, I think the answer is "No" but we do need to be very careful. Nobody wants to waste food, so it's likely that leftovers will be stored for future use. We don't want to burden our hospitals with food poisoning cases. Here are a few tips:<br />
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Keep leftovers refrigerated and reheat to at least 75C - use a thermometer<br />
Wash your hands thoroughly and frequently<br />
Don't touch your face<br />
Ensure that food is cooked properly (as you would normally) <br />
Be very wary of cross contamination of raw and cooked food<br />
Stay home; don't pop down to the corner store just to pick up a bottle of milk - plan your shopping.<br />
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Just a couple of final points:<br />
The experts now think that the wearing of masks available to the general public is not going to protect you from infection. Don't forget that the virus is tiny and if you get it in your eyes, it will run down your tear ducts into your nasal passages and can initiate an infection<br />
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I am now washing my hands more thoroughly and frequently than when I was working with green lipped mussels deliberately infected with high levels of Salmonella!John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com2tag:blogger.com,1999:blog-7580894348901105904.post-28264904976705551542019-08-17T00:56:00.000-07:002019-08-17T00:57:09.733-07:00Can this be real?<br />
It's amazing how a throwaway line can be picked up and takes on a life of its own. A New Zealand botanist referred to a lichen, <em><a href="https://www.inaturalist.org/taxa/355322-Xanthoparmelia-scabrosa">Xanthoparmelia scabrosa</a>, </em>as "Sexy Pavement Lichen" because it contains a PDE5 inhibitor. <i>See </i><span style="font-size: 16px;">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3083877/</span><br />
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<span style="font-size: 16px;">It appears that powdered <i>X. scabrosa</i> is being sold on-line as a Viagra alternative. It has even been reported that people are actually licking sidewalks! This is probably not a smart way to obtain a potential erectile disfuntion medication, as the inhibitor is not the same thing as Viagra and is also somewhat toxic, not to mention the contamination of the lichen from vehicle exhaust, dust and grit etc.</span><br />
<span style="font-size: 16px;"><br /></span><span style="font-size: 16px;">According to Tom Hale, writing for IFLScience, the US FDA analysed a sample of the powder bought on-line and found it consisted of 80% Viagra and 20% grass clippings <i>(really?)</i></span><br />
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<br />John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-45017659954837744812019-07-25T18:20:00.001-07:002019-07-25T18:20:38.775-07:00Listeria in smoked salmon - again.The Department of Health in Australia is investigating three separate cases of Listeriosis apparently associated with smoked salmon. There have been two deaths and one<br />
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This is not a reason to stop eating smoked salmon, or even cause for a massive recall. There is a couple of things we all need to know.<br />
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Firstly, no specific smoked salmon product has been recalled.<br />
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Secondly, the three cases were in three different states and occurred over the period 22nd February to 7th June. i.e. they were well separated both in location and time.<br />
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Thirdly, and probably most importantly, all three patients were over 70 years old and had other health conditions that may have predisposed them to infection by <i>Listeria.</i><br />
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This is a reminder that people who may be susceptible to listeriosis should avoid foods that are known to carry higher risk of infection.<br />
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<i>See: </i>https://foodsafetywithjaybee.blogspot.com/2011/01/listeria-hysteria.html and search the blog using keyword Listeria.<br />
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<br />John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-24154905247144390692019-07-09T20:02:00.002-07:002019-07-09T20:02:26.592-07:00A caffeine fix too farThis post is a little different from many of my articles, which have been predominantly about food microbiology.<br />
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The Sydney Morning Herald is reporting the death of a young man who dosed his protein shake with caffeine powder. <span class="sics-component__byline__author">Natassia Chrysanthos wrote an article published </span><span class="sics-component__byline__date">05:21, Jul 10 2019 about the man who returned home after celebrating New Year's Eve and made a hangover cure/workout shake and added pure caffeine powder.</span><br />
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<span class="sics-component__byline__date">Strangely, he messaged his friends that the shake tasted awful, but apparently continued to consume it. He was found dead on the bathroom floor next morning.</span><br />
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<span class="sics-component__byline__date">Caffeine is a central nervous system stimulant and we all know the lift we get from our morning cup of Joe. There is a number of benefits claimed for consumption of caffeine, but there are downsides. Caffeine withdrawal is real, particularly if you drink lots of coffee, as your body becomes tolerant of the chemical. Some people suffer headaches if they stop drinking coffee, probably because of its effect on the blood vessels of the brain.</span><br />
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<span class="sics-component__byline__date">The Mayo Clinic considers that up to 400 milligrams of caffeins is safe, and this is equivalent to about 4 cups of coffee. A teaspoonful of pure caffeine is equivalent to about 28 cups of coffee! An overdose can result in a rapid heartbeat and breathing difficulties, or may cause death due to convulsions or irregular heartbeat. </span><br />
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<span class="sics-component__byline__date">According to the FDA, it is practically impossible to measure a safe dose of highly concentrated caffeine using household utensils; the difference between a safe dose and potentially lethal amount is very small. In this case, the caffeine powder may have been given to the victim without a label.</span><br />
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<span class="sics-component__byline__date">It's very sad that a young, vibrant young man should die from consuming a home-made energy drink. We should all be aware that some chemicals that are normally found in foods and beverages can be toxic if consumed in larger amounts.</span><br />
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<span class="sics-component__byline__date"><br /></span>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-91969723210809449682019-06-22T22:37:00.001-07:002019-06-23T18:33:16.811-07:00Mussels unsafe if eaten rawMany people in New Zealand like to eat shellfish, such as mussels, raw. The Ministry of Health and New Zealand Food Safety Authority (Te Pou Oranga Kai O Aotearoa) has warned consumers NOT to eat fresh mussels harvested commercially in Coromandel, an area of the North Island, without cooking them to at least 65C.<br />
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The culprit for the current food poisonings is probably <i>Vibrio parahaemolyticus,</i> a bacterium found in marine, coastal and tidal waters, and most commonly causes gastroenteritis. It is not normally spread person to person, though poor personal hygiene, such as failure to wash hands after handling raw shellfish, could result in infections.<br />
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Symptoms usually occur within 24 hours of eating the infected food and include<br />
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<li>watery diarrhoea (occasionally bloody diarrhoea)</li>
<li>abdominal cramps</li>
<li>nausea</li>
<li>vomiting</li>
<li>fever</li>
<li>headache.</li>
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Image from Pathogen Profile Dictionary</div>
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https://www.ppdictionary.com/bacteria/gnbac/parahemolyticus.htm</div>
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There is a feeling among some experts that Vibrio parahaemolyticus entered New Zealand in imported fish or shellfish. Cross contamination in the markets then allowed its spread.</div>
John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-4491822998300272272019-05-01T21:03:00.000-07:002019-05-01T21:06:22.145-07:00Helpful Guide to Food Safety and Kitchen Clean-up - guest columnAs most readers know, I normally don't post comments that contain links to commercial sites. I get quite of lot of these, and in most cases, the writers are just trying to get clicks on their own sites.<br />
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However, occasionally a message comes along with useful information. I received an invitation recently to publish a guide to food safety and kitchen clean-up. This came from Cleaning Building Services New York.<br />
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<span style="background-color: transparent; color: #333333; font-family: "comfortaa" , cursive; font-size: 23pt; vertical-align: baseline; white-space: pre-wrap;">A Guide to Food Safety and Kitchen Clean Up</span></h1>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">An essential part of preparing a meal is making sure to use the proper food safety techniques. Without proper safety protocols your food can become contaminated and pass along foodborne illnesses to whomever eats or comes in contact with it. The </span><a href="https://www.cdc.gov/foodsafety/index.html" style="text-decoration: none;"><span style="background-color: transparent; color: #96c30c; font-family: "comfortaa" , cursive; font-size: 11pt; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">Centers for Disease Control and Prevention</span></a><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;"> (CDC) states that 48 million Americans become sick from foodborne illnesses each year. Of those 48 million people, 128,000 are so sick that they need to be hospitalized, and 3,000 people even die from the foodborne illness. To prevent foodborne illness from happening to you or your family, it is important to practice food safety protocols while handling, preparing, and storing all of your meals.</span></div>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Cleaning Up the Kitchen</span></h2>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Keeping your kitchen clean is an important step in food safety. After each meal, it is important to clean and sanitize all surfaces where food was prepared or handled. All surfaces should be washed thoroughly with hot water and soap. For a deeper clean the surfaces can even be washed with a diluted chemical mixture of 1 tablespoon bleach and one gallon of water. All cooking appliances used when preparing the meal should also be washed thoroughly inside and out. An important step that most people tend to forget about is cleaning out your refrigerator. You should be going through your refrigerator once a week to discard any expired items to prevent growing bacteria. Vegetables and Fruits should also be rinsed under water before being consumed to get rid of any pesticide residue. You should always clean your hands thoroughly after touching any raw meats or fish as well, this will help prevent transporting harmful bacteria.</span></div>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Know Your Temps</span></h2>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Foodborne Illness is caused by harmful bacteria, some of the most common being </span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; font-style: italic; vertical-align: baseline; white-space: pre-wrap;">Escherichia coli</span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">, </span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; font-style: italic; vertical-align: baseline; white-space: pre-wrap;">Salmonella</span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">, and </span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; font-style: italic; vertical-align: baseline; white-space: pre-wrap;">Staphylococcus</span><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">. This </span><a href="https://www.bbcleaningservice.com/blog/9-kitchen-hot-spots-germs/" style="text-decoration: none;"><span style="background-color: transparent; color: #96c30c; font-family: "comfortaa" , cursive; font-size: 11pt; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">harmful bacteria</span></a><span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;"> can be consumed by eating undercooked foods and can be prevented by making sure all food is being cooked to their accurate internal temperatures. This can be done by using a kitchen thermometer. Checking the internal temperature is especially important when preparing foods like meats, fish, poultry, and eggs. Before preparing a new recipe, be sure to research what temperatures your ingredients should be kept at to avoid them being in a danger zone for the harmful bacteria.</span></div>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Food Organization</span></h2>
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<span style="background-color: transparent; color: #373737; font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">When buying food at the grocery store, look for broken seals and damaged containers before putting them in the cart. Also, be sure to check expiration or sell by dates to only purchase fresh and safe to eat foods. When cashing out in the register line, be sure that your meat or fish is packaged separately to avoid juices spreading onto your other foods. Separation is key when storing your foods away at home as well. You should always store raw meat or seafood below any other foods in your refrigerator and place them in plastic bags to avoid contamination. If possible, use different cutting boards and other cooking utensils for meats or fish and veggies. If not, be sure to clean them thoroughly in between each use. Doing this will lessen the chances of leftover bacteria being transported from your raw meats or fish to your cut veggies and fruits.</span></div>
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<span style="font-family: "comfortaa" , cursive; font-size: 11pt; vertical-align: baseline; white-space: pre-wrap;">Source: </span><span style="color: #1155cc; font-family: "comfortaa" , cursive; font-size: 11pt; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;"><a href="https://www.cleaningservicenewyorkcity.com/blog/food-safety-kitchen-clean-up-guide/" style="text-decoration: none;">Cleaning Building Services</a></span></div>
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Other material from this source will appear on this blog from time to time.</div>
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Declaration: Safe Food Blog does not endorse Cleaning Building Services, not does it have any pecuniary interest in the company.John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-87357859412014438072018-12-27T18:55:00.000-08:002018-12-28T00:01:37.753-08:00McDonald's screen of death. I remain unsurprised.A recent post from IFLScience.com claims that microbiologists from London Metropolitan University conducted swabbing on touch screens in McDonald's restaurants in London and Birmingham, finding coliforms, <i>Bacillus</i> and <i>Listeria</i>. They also found <em>Staphylococcus</em>, <em>Pseudomonas</em>, <em>Enterococcus faecalis</em> and <em>Klebsiella</em>.<br />
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All of these bacteria are capably of causing infections, and you will find some discussion of these bacteria on this blog site - see labels.<br />
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But should we be surprised and should customers at McDonald's be concerned? Well, I am not at all suprised. If a microbiologist conducts swabbing in any public place, such as a supermarket, they will find all of these bacteria, perhaps on trolley handles, push plates on doors, in the toilets etc. As for the customers, if they are concerned, they could order their meal on the touch screen, then wash their hands, or use a hand sanitiser. Be honest - if you go to any fast food joint after you have been shopping in the mall, do you always wash your hands before you eat?<br />
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The original research was done for Metro (see https://metro.co.uk/2018/11/28/poo-found-on-every-mcdonalds-touchscreen-tested-8178486/). Not surprisingly, when this post was published on FaceBook, there were 1.2 thousand comments and nearly a thousand shares. My personal opinion is that this article was written and published for shock value and to boost circulation. Interestingly, a video clip posted on this same site showed that the majority of customers were not surprised by the findings and would still go and purchase food there.<br />
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Whatever you think of McDonald's or any other fast food outlet, in my opinion, the researchers are making a mountain out of a molehill, and IFLScience is making it worse. Don't pick on just one fast food chain, and think about how you protect yourself and your family from infection. <br />
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And while you are at it, think about a similar scenario in your own home.<br />
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<i><span style="color: purple;">Food for thought: How do you recognise the microbiologists around you? They are the people who use their little fingers or elbows to open doors, use a paper towel to turn the taps off in a public washbasin, use a knuckle on the touch screen and who often use hand sanitiser before eating in public<u>.</u></span></i>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-68952598238645835362018-11-05T14:04:00.000-08:002018-11-05T14:04:06.940-08:00Downside of reusable shopping bags?Supermarkets in New Zealand are discontinuing the use of single-use plastic bags as a contribution to reducing plastic pollution. (My personal view is that this is just scratching the surface of the problem - produce is still wrapped in plastic and just about everything we buy in the line of detergents, shampoos, hand creams, water etc. is packed in plastic).<br />
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Some supermarkets are offering free or very inexpensive fabric bags to carry home the purchases.<br />
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A New Zealand politician has jumped on this, quoting a discredited overseas study that suggests that the use of reusable fabric bags will result in some deaths from food poisoning.<br />
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The general opinion among experts, myself included, is that this is silly scaremongering. If meat and poultry is carried in these bags and blood or drip escapes the packaging, then the bag will be contaminated. If unwrapped salads, cured meats, cakes, pastries and bread are carried in the <i><b>same</b></i> bag, cross contamination may occur.<br />
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Just as in the kitchen, it is sensible to separate raw meats, which will be cooked, from foods that will be consumed without further cooking. Different chopping boards should be used for raw and cooked foods, and fabric bags used for raw meats should be washed regularly. This not rocket science.<br />
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Others have jumped on the bandwaggon, once again putting forward the suggestion that sale of raw chicken, which often contains <i>Campylobacter</i>, should be banned in favour of frozen products. Certainly, freezing reduces the numbers of <i>Campylobacter</i>, but does not eliminate it.<br />
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It seems to me that a slight change in mindset is required, together with a greater understanding of food hygiene.John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com1tag:blogger.com,1999:blog-7580894348901105904.post-13928922628922796352018-10-09T16:24:00.000-07:002018-10-12T11:06:49.146-07:0013,000 beef animals just went to the landfillI hope that caught your attention. I suppose you could argue that it was clickbait. The animals didn't literally walk to the landfill, but 6.9 million pounds of ground beef were recalled last week by a company called JBS because of fears that the meat was contaminated by <i>Salmonella enterica</i> serotype Newport (otherwise known as <i>S. </i>Newport<i>).</i><br />
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There is a <a href="https://newfoodeconomy.org/jbs-salmonella-newport-beef-recall-cull-dairy-cows/?utm_source=New+Food+Economy+Subscribers&utm_campaign=a74d533e69-EMAIL_CAMPAIGN_2018_10_09_08_53&utm_medium=email&utm_term=0_75a28a0eaf-a74d533e69-511575461" target="_blank">really good article</a> on this recall by Joe Fassler in The New Food Economy.<br />
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FSIS was notified of a salmonellosis outbreak on 5th September 2018 and subsequent traceback indicated that JBS was the common source. By 6th September, 57 patients in 16 states were identified as having Salmonellosis. The strain of <i>S. </i>Newport in this outbreak is being reported as being multiple antibiotic resistant, though, as far as I am aware, this reporting is based on previous outbreaks. Antibiotics are not normally used in treatment of human salmonellosis. Experts have also pointed out that cattle are the most common source of <i>S. </i>Newport.<br />
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As with many large outbreaks, the situtation is at best muddy. In general, <i>Salmonella </i>is found much less frequently in cattle herds than in chicken flocks. It is not considered an adulterant by the regulators. In some herds, the incidence of <i>Salmonella </i>is zero; in others it has been found at up to 53%. <i>Salmonella </i>enters the meat as a result of faecal contamination, from the animals or from the processing equipment. Processors are not required to test for <i>Salmonella, </i>so JBS would not have been aware of its presence in its products. Dairy cattle are not bred for meat production, but sick, low yielding cows are often culled and sent to meat works, where the meat, not being primal cuts, is ground and used with other meat in burger patties. Thus, the potentially contaminated meat is spread extensively throughout the production. You might argue that the company should test its products for <i>Salmonella </i>even though this is not a requirement. However, microbiological testing is actually unreliable as a food safety control, mainly because of the problem of getting a meaningful sample from the food, particularly if the contamination is at a low level.<br />
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Since the processors are not required to test for <i>Salmonella</i>, they cannot be compelled to recall the potentially contaminated product, but JBS has done this voluntarily. Well done!<br />
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However, several questions remain: why was this meat implicated in causing salmonellosis? There are probably many answers to this. Americans like their hamburgers rare or medium rare. USDA raised the minimum temperature for cooked hamburgers to 160 degrees Farenheit (71.1 degrees Celsius). Provided that this internal temperature is reached, <i>Salmonella </i>will be killed. But kitchen hygiene is also critical. If raw hamburger patties or mince are handled, cross contamination to other equipment, surfaces and foods can occur. (Think next time you barbeque meat patties: did your utensils contact the raw meat and then the cooked meat? I once attended a Korean BBQ where raw meat was put on a plate and then cooked before being put back onto the same plate!) Was the processing equipment thoroughly washed down and sanitised after each shift, or is there a possibiliy that the bacteria had colonised the plant, allowing continuous inoculation of the product? Certain designs of equipment are notorious for being very difficult to clean and providing niches for colonisation. <br />
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A more general and worrying question: <i>S. </i>Newport is most commonly found in cattle and antibiotics are not normally used in treatment of human salmonellosis. Why are we finding <a href="https://foodsafetywithjaybee.blogspot.com/2011/11/time-to-ban-antibiotic-use-in-animal.html" target="_blank">multiple antibiotic resistant</a> <i>S. </i>Newport strains?<br />
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<b>Take-home message</b>: treat all meat as potentially contaminated with pathogens like <i>Salmonella. </i>Handle it carefully and cook it properly.John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-41911901009836091092018-08-20T22:16:00.000-07:002018-08-20T22:16:05.031-07:00Wines by modern Prometheus?I recently read an <a href="https://www.stuff.co.nz/life-style/food-wine/drinks/106031053/frankenstein-wine-warning-over-french-supergrapes" target="_blank">article</a> entitled<span style="font-weight: normal;"> <i>'Frankenstein wine' warning over French supergrapes.</i></span><br />
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<span style="font-weight: normal;">Apparently, French wine scientists have developed some vines that are impervious to fungal attack, specifically </span><span style="font-weight: normal;">downy mildew and powdery mildew, and therefore requiring little or no fungicidal chemicals. You'd think that this was a good thing and would be welcomed.<i> </i>But no, some people, who may have a vested interest in turning back innovation, are claiming that the "lab-grown creations" combine genes from around the world and could </span>lead to dumbed-down, low-grade "Frankenstein wine", whatever the hell that means. The implication is that the new varieties are somehow unnatural. As far as I can tell, genetic engineering has not been involved; conventional cross breeding has been used.<br />
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Let's just step back from this hysterical attack on scientific improvement in winemaking. As a result of claimed cancer links among grape growers, the French are under intense pressure to reduce the amount of fungicides used. The use of these new varieties would therefore seem to be a good move. However, a winemaker and researcher from western France has claimed that these vines, which are hybrids, would lead to "artificial and unnatural 'Frankenstein wine'." According to the article, he likened the development of the new vines to crossing a monkey with a man - technically feasible but going against nature. That is a completely over-the-top reaction, but I'd be keen to see the resulting animal!<br />
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The development and growing of hybrid grape varieties has in fact been going on since the 1950s in the northeast and Pacific Northwest of North America. Those varieties have enabled production of wines in these short season, cooler and more humid areas. They also have greater resistance to disease and therefore require less use of chemicals.<br />
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Though rare, natural interspecific hybrids do occur as a result of cross-pollination, the earliest known was discovered in 1740 near a vineyard planted in <i>Vitis vinifera.</i> <br />
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<span style="font-weight: normal;"></span>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-90967916578720411142018-08-07T15:59:00.001-07:002018-08-16T12:52:33.536-07:00FDA issues an update statement on Yuma E coli outbreakEarlier this year, a serious <span style="color: purple;"><span style="background-color: #ffe599;"><span style="color: magenta;"><a href="https://foodsafetywithjaybee.blogspot.com/2018/06/e-coli-strikes-again.html" target="_blank">multi-state outbreak</a></span></span> </span>of <i>Escherichia coli</i> O157:H7 infection was associated with consumption of Romaine lettuce from Yuma, Arizona.<br />
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The US FDA has now issued an update statement, though the investigation is not completed. Tests of canal water close to the lettuce growing farms has tested positive for the outbreak strain of <i>E. coli </i>O157:H7, which is capable of producing Sh<span style="background-color: white;"></span>igatoxin. Infection with this microorganism can result in serious disease - 210 people in 36 states have become ill, with 96 hospitalizations and five deaths.<br />
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No single farm has been determined as the source of the outbreak, nor has the distribution chain been implicated so far.<br />
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The lettuce growing farms and canal are close to a Concentrated Animal Feeding Operation (CAFO), which can
hold in excess of 100,000 head of cattle at any one time. Since cattle can harbour the <span style="color: purple;"><a href="https://foodsafetywithjaybee.blogspot.com/2012/01/want-to-know-more-about-origin-of.html" target="_blank">STEC <i>E. coli </i></a></span>involved in the outbreak, there is the possibility that the presence of the bacteria in the canal water originated from the CAFO. Further testing of the CAFO and the animals would be necessary to establish a link.<br />
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The means by which the lettuces became contaminated must also be investigated. Was the canal water used directly for irrigation, or were the bacteria somehow transferred from the canal water to the leaves?John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-69267343526456426392018-08-02T16:11:00.001-07:002021-07-08T12:47:43.834-07:00Safe Food - Product Lifetime of the blogAll products have a lifetime, after which sales drop off. The usual response is either to discontinue the line, or to set the New Product Developers (NPD) to updating the product. Think of ice cream. There will probably always be a market for ice cream, but the flavours of your childhood have been surpassed and the presentation has changed dramatically. You now have the options of ice creams on sticks, with creamy toffee, chocolate or fruit puree centres, coated in chocolate and nuts etc.<br />
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Safe Food first appeared in November 2006 while I was working at Hong Kong University. The wide varieties of foods in HK are completely different from those of our adopted country, New Zealand, though the safety issues are similar. I felt the need to write about the hazards associated with foods to help ordinary folk and food manufacturers to understand food safety, with the aim of reducing the incidence of food-mediated illness. I hoped the blog would become a resource for teachers in schools.<br />
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I have no idea whether these lofty aims were successful! The blog has only 10 followers 😢 but in the 12 years I have been writing it, there have been nearly 348,000 page views, so I guess that means that some people have found it useful.<br />
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Very few people have left comments on the blog, though some have contacted me directly - usually young mothers who have had food scares with their babies and young children.<br /><br />There are only so many unique food safety incidents to report on. Often contamination and recalls merely reflect the sad fact that manufacturers, distributors and consumers don't learn from earlier incidents. This is one of the reasons that Safe Food has not been published so frequently in the years since I retired from full time teaching and research. Perhaps the blog has become stale and "same old, same old".<br />
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It's time for some NPD! I have decided to continue writing the blog, but I want to widen the scope just a bit so that I can comment on some of the food myths that are now so frequently proliferated by minor celebrities, fanatics and those who can best be described as "loonies". There are exciting new developments in foods, such as the plant-based milk and meat substitutes, most recently exemplified by Air New Zealand's offering The Impossible Burger on some of its flights, and I want to discuss these evolutions in food supply.<br />
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I may also update the appearance of the blog, so, watch this space and please consider bookmarking, as the option for e-mail following is to be removed by Google in July 2021.<br />
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<br />John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com1tag:blogger.com,1999:blog-7580894348901105904.post-21137584600611534562018-08-01T14:56:00.002-07:002018-08-01T14:56:27.869-07:00I've been served some pretty awfull coffee in my time ...Many people on Twitter are reporting that a pregnant woman in Alberta ordered a latte at a McDonald's but was served a cup containing cleaning fluid.<br />
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According to a report on CBC News, this was caused by the coffee machine still being connected to two cleaning solution supply lines, rather than the milk reservoir. The cleaning chemical was a mixture of <span>citric acid, phosphoric acid, methyl-trimethyl-3, and 2-butoxyethanol. There is no doubt that ingestion of this material would be harmful.</span><br />
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<span>It's not clear whether the cup contained hot liquid, though if the machine were set to deliver coffee, but connected to a cleaning chemical supply, it's likely that the cup did feel normal, and since it was a takeaway, it would have been fitted with a lid, so gave no indication that it didn't contain latte. </span><br />
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<span>This potentially very dangerous incident gives a lesson: if you are a pilot, a car driver, or the operator of a food processing machine, the principles are pretty much the same - the pre-start checks must always be conducted before any start and done properly.</span>John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com2tag:blogger.com,1999:blog-7580894348901105904.post-52357836077122464772018-06-03T16:05:00.000-07:002018-06-03T16:05:37.600-07:00E. coli strikes againFive people in the United States have died since March and approximately 200 are sick as a result of an <i>Escherichia coli</i> infection apparently acquired from romaine lettuces grown in the Yuma region of Arizona. However, the authorities have been unable to pinpoint the source of the contamination.<br />
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Though <i>E. coli</i> are found in the gut of man and animals, only certain strains cause serious illness. These strains have assembled many genes that enable them to attach to the cells lining the intestine and produce very damaging toxins called Shigatoxins. This is an example of the <a href="https://foodsafetywithjaybee.blogspot.com/2011/06/evolution-in-action.html">continuous evolution of bacteria</a>. Many of these new strains are the result of <a href="https://foodsafetywithjaybee.blogspot.com/2012/03/giving-bacteria-cold.html">bacteriophage</a> infection transferring genes between bacteria or possibly by direct transfer between strains. <br />
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Various posts responding to news reports of the outbreak have suggested washing the lettuces as a means of preventing illness. Unfortunately, washing, even in chlorinated water, will not guarantee removal of the bacteria, as they can attach to the lettuce or even localise in the stomata of the leaves. I obtained the following image from https://www.inverse.com/article/28938-e-coli-detection-lettuce-feces.<br />
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<a href="https://2.bp.blogspot.com/-ZRlJhL9jgR4/WxRxn1TpsgI/AAAAAAAAA84/Qrlol-70260QCNGsBJsewaWeMRkaGTCtQCLcBGAs/s1600/Lettuce%2Bstoma.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="650" data-original-width="1300" height="160" src="https://2.bp.blogspot.com/-ZRlJhL9jgR4/WxRxn1TpsgI/AAAAAAAAA84/Qrlol-70260QCNGsBJsewaWeMRkaGTCtQCLcBGAs/s320/Lettuce%2Bstoma.jpeg" width="320" /></a></div>
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You can see bacteria within the stoma; it is clear that they would be very difficult to wash out.<br />
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This outbreak was originally thought to be caused by bagged and chopped lettuce, but inmates in a prison in Alaska also became ill after eating whole head lettuce. In view of these facts, it is unfortunate that consumer advocates are urging the FDA to introduce new rules to speed up investigation of such outbreaks. It is hard to see how new rules would influence the investigations, given that it has so far been impossible to tie the contamination to a single farm, processor or distributor.<br />
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The one fairly sure conclusion is that the lettuces have become contaminated with faeces, since this <i>E. coli</i> is not a natural inhabitant of the environment.<br />
John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-26061335245943801322018-03-28T18:47:00.000-07:002018-03-28T18:47:37.750-07:00On the turps - it's insane.In New Zealand where I live, we have a phrase "On the turps". It means "drinking alcohol" usually, but not always, beer. When you've been on the turps, you may have a hangover if you were serious about it.<br />
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I have a thing about ill-informed food and drink advice, some of which is downright dangerous. Totally unqualified people seem to think that they can hand out advice on diet, so-called "super foods" and other health issues.<br />
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The latest whacky outpouring from a minor celebrity suggests that drinking a small quantity of turpentine with sugar will rid you of a cold overnight. This is a BAD IDEA.<br />
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Turpentine is prepared from the resin of pine trees and, I have to say, smells really nice and fresh. I used it when I was painting in oils to thin the paint. Another person giving the advice, this time a disbarred doctor, claims that her IQ "went up like 50 points". I think she has the sign wrong - it should be -50 points.<br />
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There is plenty of <a href="https://www.cdc.gov/niosh/idlh/8006642.html">scientific evidence</a> to show that turpentine is poisonous, causing irritation to the eyes and central nervous system and severe damage to the kidneys, or, in sufficient quantities, death.<br />
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We have been considering natural turpentine here. Hardware stores sell "mineral turps" which is a turpentine substitute prepared from petroleum. Consumption of mineral turps may not be fatal, but can result in lung damage and irreversible brain damage.<br />
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Of course, this post is not strictly about food safety, but I believe it is important to get this message out there.<br />
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I feel so strongly about misleading food and nutrition advice that I am chairing a conference in New Zealand with the theme "In food we trust: confidence built on science and technology".John Brookshttp://www.blogger.com/profile/02097598262611464287noreply@blogger.com0tag:blogger.com,1999:blog-7580894348901105904.post-83379284794338729562018-03-26T15:40:00.001-07:002018-03-26T16:07:13.102-07:00A useful Sanitation Checklist.This checklist was sent to me by Meyer Industrial Solutions. I have provided it for the benefit of readers, without endorsement of the company.<br />
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There are a couple of things that I think merit comment:</div>
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<li>Step 1. The use of compressed air to move residues may have the effect of spreading them around the processing area. Better to manually sweep.</li>
<li>Step 2. If the equipment is contaminated with proteinaceous material, I recommend using <i>warm water</i> for the intial rinse. Hot water may set the protein and make it more difficult to remove.</li>
<li>Step 3. I agree that the use of pressurised water for rinsing tends to spread contamination around. I once visited a meat processing facility and found meat scraps on the ceiling, put there by pressurised water!</li>
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This was created by <a href="http://www.meyerindustrial.com/products/rotary-airlock-feeders/">Meyer Industrial</a></div>
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