Are 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?
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.
New Zealand, where I live, has closed its borders.
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.
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!
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.
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:
Keep leftovers refrigerated and reheat to at least 75C - use a thermometer
Wash your hands thoroughly and frequently
Don't touch your face
Ensure that food is cooked properly (as you would normally)
Be very wary of cross contamination of raw and cooked food
Stay home; don't pop down to the corner store just to pick up a bottle of milk - plan your shopping.
Just a couple of final points:
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
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!
Showing posts with label food safety. Show all posts
Showing posts with label food safety. Show all posts
Saturday, April 11, 2020
Tuesday, July 9, 2019
A caffeine fix too far
This post is a little different from many of my articles, which have been predominantly about food microbiology.
The Sydney Morning Herald is reporting the death of a young man who dosed his protein shake with caffeine powder.
The Sydney Morning Herald is reporting the death of a young man who dosed his protein shake with caffeine powder.
Thursday, December 27, 2018
McDonald'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, Bacillus and Listeria. They also found Staphylococcus, Pseudomonas, Enterococcus faecalis and Klebsiella.
All of these bacteria are capably of causing infections, and you will find some discussion of these bacteria on this blog site - see labels.
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?
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.
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.
And while you are at it, think about a similar scenario in your own home.
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.
All of these bacteria are capably of causing infections, and you will find some discussion of these bacteria on this blog site - see labels.
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?
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.
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.
And while you are at it, think about a similar scenario in your own home.
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.
Monday, November 5, 2018
Downside 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).
Some supermarkets are offering free or very inexpensive fabric bags to carry home the purchases.
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.
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 same bag, cross contamination may occur.
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.
Others have jumped on the bandwaggon, once again putting forward the suggestion that sale of raw chicken, which often contains Campylobacter, should be banned in favour of frozen products. Certainly, freezing reduces the numbers of Campylobacter, but does not eliminate it.
It seems to me that a slight change in mindset is required, together with a greater understanding of food hygiene.
Some supermarkets are offering free or very inexpensive fabric bags to carry home the purchases.
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.
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 same bag, cross contamination may occur.
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.
Others have jumped on the bandwaggon, once again putting forward the suggestion that sale of raw chicken, which often contains Campylobacter, should be banned in favour of frozen products. Certainly, freezing reduces the numbers of Campylobacter, but does not eliminate it.
It seems to me that a slight change in mindset is required, together with a greater understanding of food hygiene.
Wednesday, August 1, 2018
I'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.
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 citric acid, phosphoric acid, methyl-trimethyl-3, and 2-butoxyethanol. There is no doubt that ingestion of this material would be harmful.
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.
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.
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 citric acid, phosphoric acid, methyl-trimethyl-3, and 2-butoxyethanol. There is no doubt that ingestion of this material would be harmful.
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.
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.
Wednesday, April 5, 2017
Fermented foods - tasty, safe and good for you.
Recently, one of my regular readers watched a BBC television programme on
"Which foods can improve your gut bacteria?" narrated by Dr. Michael Mosley. She wrote and asked me to comment on the safety of such foods, how they should be stored, plus potential risks of manufacturing them at home.
Traditional, naturally fermented foods have been around for hundreds, if not thousands, of years. These days, we tend to relate the term "Fermented food" to sauerkraut, kimchi, tempeh, or perhaps yoghurt and cheese. However, the Egyptians knew about wine production 5,000 years ago (though they didn't know that yeasts were involved).
Fermentation is a natural process, carried out by bacteria, yeasts and occasionally moulds, that actually preserves raw foods, often by production of acid or alcohol, which prevent spoilage. Of course, the preserved food sometimes bears little resemblance to the original. We enjoy these foods because the fermentation changes the flavour and texture of the raw material, often increasing the complexity.
We now know that our gut microflora, now called the gut biome, can be influenced for the better by consumption of some fermented foods. The microorganisms that carry out the fermentation can sometimes pass through the very acid conditions of the stomach and may be able to colonise the gut wall, perhaps displacing undesirable bacteria, though some just pass through, having a transitory effect on the gut biome. They can help with traveller's diarrhoea or lactose intolerance.
Dr. Mosley and his team investigated the claims for such benefits by setting up three groups to consume various fermented products for four weeks and looked for changes in their gut bacteria. You can read about it in the link above.
The team also tested the products to determine the range of bacteria in them. Home-made fermented foods tended to contain a diverse range of bacteria, while commercial products, which may have been pasteurised, often contained very few. Thus the flavours and textures would be similar, but the potential health benefits of the microbial populations had been removed.
Over many years of teaching food microbiology, I made sauerkraut with my students. It's an easy fermentation to carry out, requiring only finely shredded cabbage and about 2 - 2.5% salt packed in a suitable container. Air must be excluded to prevent the growth of moulds on the surface of the kraut. We followed the fermentation daily, counting and identifying the bacteria taking part, and measuring the titratable acidity and pH.
We always found a succession of bacteria. The undesirables, like Escherichia coli and other coliforms disappeared within the first couple of days as lactic acid bacteria produced lactic acid and reduced the pH. Leuconostoc species, found on the inside leaves of the cabbage, would begin the acid production, giving way to Lactobacillu plantarum and eventually L. brevis. The final pH of the sauerkraut is around 3, which is plenty low enough to prevent the growth of pathogens.
The kraut can be stored in the refrigerator for a short time, but must be protected from oxygen to prevent spoilage. If you would like to make some at home, download the original recipe, written by Carl S. Pederson in 1939. He studied the fermentation extensively over many years. There are many other, more recent recipes available on-line and much has been published in the scientific literature on the microbiological changes that occur during fermentation. You can also find many recipes for kimchi on-line.
Are home-made fermented vegetables safe to consume? Yes, provided that the fermentation has produced sufficient acid to lower the pH to around 3 to 3.5, which will prevent the growth of pathogenic bacteria. The finished product must not be allowed to go mouldy, since moulds can metabolise the acid and raise the pH to levels at which pathogens could grow. My son, who is an electronics engineer, has successfully made sauerkraut and kimchi at home. You don't need to be a microbiologist or food technologist to make safe, tasty fermented foods!
Tuesday, February 7, 2017
Brexit, Trump and food safety fears
The decision by Britain to leave the EU would not immediately spring to mind as a cause for concern over food safety. Neither would the election of Donald Trump as President of the USA.
However, decisions made in haste or with little forethought can often have unexpected consequences.
It now appears that a trade agreement between the US and UK might result in food products banned in the EU being imported into the UK. This might include beef from cattle implanted with growth hormones, chlorine-washed chicken, and unlabelled genetically modified (GM) foods.
This has resulted in a furore on FaceBook, though the concern about chlorine-washed chicken is a little surprising. Chlorine rinses are used extensively in the food industry to reduce surface contamination on vegetables, during chicken processing and for sanitation of equipment during food processing.
Of course, chlorine is also used in water treatment for decontamination of potable water supplies where UV treatment is not used, perhaps for cost cosiderations.
Over the years, a lot of work has been done on the effects of chlorine in foods. At the levels used for practical decontamination, there is no risk to human health, though some chemical changes are inevitable.
If you are keen to follow up on this, The Institute for Environmental and Scientific Research Limited, (ESR) in New Zealand produced a report in 2008 for the New Zealand Food Safety Authority: Client Report FW0883 CHLORINATED COMPOUNDS FORMED DURING CHLORINE WASH OF CHICKEN MEAT.
It is available on-line at: http://www.foodsafety.govt.nz/elibrary/industry/chlorinated-compounds-formed-research-projects/FW0883_Chlorinated_compounds_in_chicken_meat.pdf
The report stated that "In conclusion, no safety issues were identified due to the use of chlorine dioxide and ASC for poultry carcass disinfection. Chlorination reactions appear to be insignificant for these compounds and oxidation reactions do not appear to result in significant alteration of the fatty acid and amino acid composition of poultry carcasses". Further, the authors stated " ...we consider that there is insufficient evidence to justify further investigation of the risks to human health from the use of these disinfection chemicals in poultry processing".
Saturday, August 6, 2016
Expert comment on potential hazards of oxidised fish oil
Scientists are often misunderstood and maligned by the general population and by writers of popular diet and health articles. However, within the scientific community, publication of research and critical evaluation by other scientists is the norm, and leads to greater understanding of our health and wellbeing.
My friend and colleague, Dr. Laurence Eyres, is a fats and oils chemist. He has written the following article on studies concerning oxidised fish oil.
Oxidised Fish Oil
The authors of a controversial fish oil supplements paper have published another paper on the potential deleterious effects of oxidised fish oils. This has now been picked up and blown out of context by The Listener in New Zealand (Week July 30-August 5).
The wider lipid scientific community were surprised and highly disappointed by the original early 2015 Nature Science Reports (NSR) paper by the University of Auckland. The Therapeutic Goods Authority of Australia (TGA) performed follow up analyses, and all Australasian (ANZ) oils were not oxidised, and Omega-3 content met label claims. Earlier ANZ studies had reported similar findings but were not cited by the NZ authors. These results have been communicated to NSR, and journal feedback is still being waited on. The TGA took no actions against ANZ manufacturers, once again in keeping with the wider view that the fish oil products were meeting their omega-3 claims and were not heavily oxidised.
The justification for the new paper appears to be driven / justified by the NSR paper, which we refer to above. This NSR paper remains in the strongest doubt/dispute. The new paper uses heavily oxidised oil that the NZ authors prepare. As ANZ fish oils are NOT oxidised, the study is seen as not relevant. This is the view of many scientists who have seen the new paper. The peroxide value (PV) result of the oil, indicating primary oxidation, is exceptionally high, further indicating that the use of such an oil is not relevant. The dose used is equated to 40 mL per day for a human consumer. This dose is seen as exceptionally excessive. Few consumers would be taking more than 1-3 g per day. Nutritionists would advise increasing the level of Vitamin E if high levels of polyunsaturated fatty acids are used for feeding any mammal.
The unoxidised oil actually and interestingly shows improvement in the new paper versus the control treatment, although little is stated by the NZ authors on this aspect. Also the unoxidised oil had improved survival rates in the studied rats, and so whilst we totally agree that women who are pregnant should not consume rancid oils, they do need omega-3.
This author spoke about oxidised lipids at the recent NZIFST conference. The oils and fats group has held several seminars on the toxicity of oxidised fat over the years and it has been a stance of ours that we should not consume any oxidised oils. There are many other significant sources of oxidised fats in normal human diets other than fish oil. These include used and abused frying fats, bottled oils and rancid nuts such as walnuts. The topic of toxic aldehydes from such highly oxidised fats was covered in a recent issue of Inform magazine.
The authors in their introduction state “that in animal models, exposure to oxidised lipids has been shown to cause harm, including growth retardation, organ toxicity, and accelerated atherosclerosis. However, the effects of consuming oxidised lipids during pregnancy are unknown. For this reason, this latest study was designed to investigate the effects of fish oil supplementation during pregnancy on the adult offspring of rats fed a high-fat diet, and they also included oxidised fish oil groups. As obesity is associated with increased oxidative stress and greater production of oxidised lipids, the effects of an oxidised lipid supplement may be more marked in obese mothers.
The study is very interesting and will be probably the subject of more media hype. However, a couple of comments. The fish oil (unspecified as to composition) was oxidised artificially to really highly rancid and toxic levels and then used in the rats at levels 20-40 times a normal human dose.
Any relevance to the consumption of omega-3 supplements in humans is likely to be none.
Thursday, October 22, 2015
MPI provides an interactive tool to determine your responsibilities under The Food Act 2014
The New Zealand Food Act 2014 comes into force on 1st March, 2016. This will not be news to major food manufacturers, but does affect everyone working in the food industry; their responsibility is to produce safe food.
The new Act focusses on the processes of food production, rather than the premises where these activities are carried out. i.e. the old "floors, walls and ceilings" approach is long gone. The other major difference from earlier legislation is that it takes account of the risk associated with any particular business (and that includes the activities of clubs and societies that raise funds via sales of food, such as pizzas). The new Act brings in Food Control Plans for high risk food production and supply (in fact, many businesses have been operating under FCPs for some time), and introduces National Programmes for activities with lower risk. Thus manufacture of ice cream is treated rather differently from the sale of coffee from a mobile operation at shows and open days.
One of the problems currently faced by smaller operations, such as corner dairies, saussage sizzles and community shared meals like club gatherings for members and guests, where food may be sold, but not as the primary purpose of the gathering, is knowing exactly what is required in terms of the regulations. The New Zealand Ministry of Primary Industries (Te Manatu Ahu Matua) has provided an easy-to-use interactive tool to help all organisations involved in producing, selling and providing food to determine their responsibilities under the new Act. The tool is called Where do I fit? and poses a series of questions you can answer by clicking responses. The tool will then tell you your responsibilities and the requirements of the Act, together with links to further information.
I have not tested the tool extensively, but it is very easy to use and provides lots of helpful information. I specifically tested it from the perspective of my gliding club's putting on a fundraiser and found the output very helpful.
The new Act focusses on the processes of food production, rather than the premises where these activities are carried out. i.e. the old "floors, walls and ceilings" approach is long gone. The other major difference from earlier legislation is that it takes account of the risk associated with any particular business (and that includes the activities of clubs and societies that raise funds via sales of food, such as pizzas). The new Act brings in Food Control Plans for high risk food production and supply (in fact, many businesses have been operating under FCPs for some time), and introduces National Programmes for activities with lower risk. Thus manufacture of ice cream is treated rather differently from the sale of coffee from a mobile operation at shows and open days.
One of the problems currently faced by smaller operations, such as corner dairies, saussage sizzles and community shared meals like club gatherings for members and guests, where food may be sold, but not as the primary purpose of the gathering, is knowing exactly what is required in terms of the regulations. The New Zealand Ministry of Primary Industries (Te Manatu Ahu Matua) has provided an easy-to-use interactive tool to help all organisations involved in producing, selling and providing food to determine their responsibilities under the new Act. The tool is called Where do I fit? and poses a series of questions you can answer by clicking responses. The tool will then tell you your responsibilities and the requirements of the Act, together with links to further information.
I have not tested the tool extensively, but it is very easy to use and provides lots of helpful information. I specifically tested it from the perspective of my gliding club's putting on a fundraiser and found the output very helpful.
Thursday, February 26, 2015
At what point do we start to trust scientific opinion?
I have spent quite a bit of time recently trying to sort out the difference between demonstrable scientific fact and informed scientific opinion. An example of the former is the measurement of 'g', the acceleration due to gravity; the latter might be the opinion of medical practitioners and nutritionists that consumption of large amounts of saturated fat can lead to heart disease. Few people would argue about 'g', but there is much discussion, even amongst the experts, about the effects of saturated fat in the diet. An opinion gains validity when, if challenged, it can be supported by peer-reviewed research.
Of course, it is impossible to prove a negative, but at what point do we say "The overwhelming evidence indicates that ..."
At what point do we trust the opinions?
I found the following graphic on-line. Click on the image to see it full size if it doesn't display properly in your browser. I was surprised at how many learned groups had made these opinions known. I am not going to state my own opinions here - I don't consider myself an expert in the field, but my training as a scientist does allow me to evaluate evidence provided to me in peer-reviewed literature. It would be a very long stretch to claim that all of these individuals and groups were either supported by, or influenced by the companies producing GM foods.
Of course, it is impossible to prove a negative, but at what point do we say "The overwhelming evidence indicates that ..."
At what point do we trust the opinions?
I found the following graphic on-line. Click on the image to see it full size if it doesn't display properly in your browser. I was surprised at how many learned groups had made these opinions known. I am not going to state my own opinions here - I don't consider myself an expert in the field, but my training as a scientist does allow me to evaluate evidence provided to me in peer-reviewed literature. It would be a very long stretch to claim that all of these individuals and groups were either supported by, or influenced by the companies producing GM foods.
Tuesday, December 23, 2014
Happy and safe Christmas to you all
For us in New Zealand, Christmas Day is only 12 hours away. It is summer and we will be having BBQs and parties outside.
Don't forget - if you are cooking outside on a fire or a BBQ, steak requires only to be cooked on the outside, as the inside of meat from a healthy animal is essentially sterile. If the steaks are thick, make sure that the edges are also cooked. However, meat patties have been made by blending together minced meat and possibly egg as a binder. The inside of the patty is not sterile and so the patties must be cooked through properly. Use a meat thermometer to be sure that the inside has reached at least 75C. You can't judge whether the meat is cooked just by its colour.
I prefer not to cook chicken on the BBQ because it is difficult to ensure even heating. However, if the BBQ has a hood, it is essentially the same as an indoor oven. Ensure that the chook is cooked properly, again using a meat thermometer. I also prefer not to put stuffing into the body cavity - it slows down the cooking process and it's difficult to determine when it's done. Cook the seasoning separately.
Round our place, there are very rarely any leftovers. However, make sure that food doesn't stay in the sun any longer than necessary. Ham that has been handled may well be contaminated with Staphylococcus. If eaten straight away, this is no problem, but if left at room temperature, the bacteria may grow, since all their competitors have been killed in the preparation process, leaving them free to grow in the salty favourable conditions.
Remember that several food borne pathogens can grow, albeit slowly, in the refrigerator, so use leftovers within a day or so.
Recent changes in legislation in New Zealand mean that driving after more than one alcoholic drink risks being charged with driving under the influence of alcohol. Better to have a designated driver, or stay off the turps!
To all my readers, I wish a happy Christmas and an enjoyable New Year.
Don't forget - if you are cooking outside on a fire or a BBQ, steak requires only to be cooked on the outside, as the inside of meat from a healthy animal is essentially sterile. If the steaks are thick, make sure that the edges are also cooked. However, meat patties have been made by blending together minced meat and possibly egg as a binder. The inside of the patty is not sterile and so the patties must be cooked through properly. Use a meat thermometer to be sure that the inside has reached at least 75C. You can't judge whether the meat is cooked just by its colour.
I prefer not to cook chicken on the BBQ because it is difficult to ensure even heating. However, if the BBQ has a hood, it is essentially the same as an indoor oven. Ensure that the chook is cooked properly, again using a meat thermometer. I also prefer not to put stuffing into the body cavity - it slows down the cooking process and it's difficult to determine when it's done. Cook the seasoning separately.
Round our place, there are very rarely any leftovers. However, make sure that food doesn't stay in the sun any longer than necessary. Ham that has been handled may well be contaminated with Staphylococcus. If eaten straight away, this is no problem, but if left at room temperature, the bacteria may grow, since all their competitors have been killed in the preparation process, leaving them free to grow in the salty favourable conditions.
Remember that several food borne pathogens can grow, albeit slowly, in the refrigerator, so use leftovers within a day or so.
Recent changes in legislation in New Zealand mean that driving after more than one alcoholic drink risks being charged with driving under the influence of alcohol. Better to have a designated driver, or stay off the turps!
To all my readers, I wish a happy Christmas and an enjoyable New Year.
Thursday, November 13, 2014
The wonder fat?
This press release came to me via the NZIFST FaceBook Group of the same name. See
The bad oil on coconut oil.pdf
The bad oil on coconut oil.pdf
The original article was released by a marketing, PR and communications consultancy consultancy, AMG.
Like many snake oil adverts, this release contains some grains of truth. However, it also make many unsubstantiated health claims, which is illegal in New Zealand.
I'm not going to comment on the release; suffice it to say that I shall not be buying any of the product. Have a look and decide for yourself whether this is the sort of oil that you want to use for cooking and treating your family.
I'm not going to comment on the release; suffice it to say that I shall not be buying any of the product. Have a look and decide for yourself whether this is the sort of oil that you want to use for cooking and treating your family.
Wednesday, March 12, 2014
Unsafe Hospital Food? There is a greater concern
A couple of days ago, I came across a reference to a report that claimed 85% of raw chicken delivered to the University Hospital in Geneva tested positive for strains of Escherichia coli resistant to extended-spectrum beta lactam antibiotics. These antibiotics belong to the penicillin family. The original study was published in Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America. (Unfortunately, when I tried it, the link was broken).
Apparently, there were workers in the hospital kitchen who tested positive to carriage of the ESBL E. coli, however, the frequency was no greater than in the general population.
The finding of the high rate of contamination with ESBL resistant bacteria in the raw chickens is a concern, not because patients were at risk, but because it indicates that the poultry flocks had probably been exposed to antibiotics that are still used in therapy. Proper procedures in the kitchens should ensure that the contaminating bacteria are destroyed and that cross contamination from raw meat to cooked or fresh foods is controlled.
The use of antibiotics in animal husbandry is leading to increased incidence of antibiotic resistant bacteria. See my previous posts on antibiotics: http://foodsafetywithjaybee.blogspot.co.nz/2011/11/time-to-ban-antibiotic-use-in-animal.html
et seq.
When I gave my inaugural lecture as Professor of Food Microbiology, I reviewed the developments in microbiology that led to the discovery and development of penicillin. Before the advent of this antibiotic, a simple scratch with a rose thorn could be a death sentence if the scratch became infected. It would be a catastrophe if we returned to those days because we had squandered our slim advantage over the pathogenic bacteria for short term financial gains by the animal rearing industries.
Apparently, there were workers in the hospital kitchen who tested positive to carriage of the ESBL E. coli, however, the frequency was no greater than in the general population.
The finding of the high rate of contamination with ESBL resistant bacteria in the raw chickens is a concern, not because patients were at risk, but because it indicates that the poultry flocks had probably been exposed to antibiotics that are still used in therapy. Proper procedures in the kitchens should ensure that the contaminating bacteria are destroyed and that cross contamination from raw meat to cooked or fresh foods is controlled.
The use of antibiotics in animal husbandry is leading to increased incidence of antibiotic resistant bacteria. See my previous posts on antibiotics: http://foodsafetywithjaybee.blogspot.co.nz/2011/11/time-to-ban-antibiotic-use-in-animal.html
et seq.
When I gave my inaugural lecture as Professor of Food Microbiology, I reviewed the developments in microbiology that led to the discovery and development of penicillin. Before the advent of this antibiotic, a simple scratch with a rose thorn could be a death sentence if the scratch became infected. It would be a catastrophe if we returned to those days because we had squandered our slim advantage over the pathogenic bacteria for short term financial gains by the animal rearing industries.
Thursday, November 14, 2013
The two/five/ten second rule
I was contacted today by a TV presenter who wanted me to comment on the supposed rule that says "If you drop food on the floor, it's OK to eat it if you pick it up before two, five or ten seconds". The length of time depends on who tells you the rule.
THERE IS NO RULE!
Think of the possible permutations: you drop a chocolate on your clean carpet; you drop a lettuce leaf on your clean kitchen floor and perhaps rinse it under the tap; you always take your shoes off when you enter the house and you drop a sandwich on the clean carpet; you are out at the races and your kid drops his hotdog on the grass.
These situations are very different, but they all have one thing in common: the floor, carpet and grass are all places where people tread and possibly where animals tread too. Even in your clean house, there may be pets that shed hair and you have no idea which part of their anatomy is shedding.
If it's OK to do it at home, would you be happy to see food dropped on the floor in a restaurant picked up and put back on a plate?
I guess ultimately, it's a matter of personal opinion, at least in the domestic situation, but we know that microorganisms can transfer from one surface to another with amazing rapidity. The chances of getting an infecting dose of pathogens from eating food that has momentarily been on the floor is small, but is it worth the risk? What else is on the floor?
The difficulty, of course, is that you wouldn't give a baby food that has been dropped on the floor, but as soon as the baby starts to crawl, it will put anything in its mouth and thereby starts to build up immunity to bacteria in its environment. How do you decide?
For what it's worth, my professional opinion is that no food should be consumed if it has been on the floor.
THERE IS NO RULE!
Think of the possible permutations: you drop a chocolate on your clean carpet; you drop a lettuce leaf on your clean kitchen floor and perhaps rinse it under the tap; you always take your shoes off when you enter the house and you drop a sandwich on the clean carpet; you are out at the races and your kid drops his hotdog on the grass.
These situations are very different, but they all have one thing in common: the floor, carpet and grass are all places where people tread and possibly where animals tread too. Even in your clean house, there may be pets that shed hair and you have no idea which part of their anatomy is shedding.
If it's OK to do it at home, would you be happy to see food dropped on the floor in a restaurant picked up and put back on a plate?
I guess ultimately, it's a matter of personal opinion, at least in the domestic situation, but we know that microorganisms can transfer from one surface to another with amazing rapidity. The chances of getting an infecting dose of pathogens from eating food that has momentarily been on the floor is small, but is it worth the risk? What else is on the floor?
The difficulty, of course, is that you wouldn't give a baby food that has been dropped on the floor, but as soon as the baby starts to crawl, it will put anything in its mouth and thereby starts to build up immunity to bacteria in its environment. How do you decide?
For what it's worth, my professional opinion is that no food should be consumed if it has been on the floor.
I don't know where this image originated; I found it on the Internet.
Wednesday, August 28, 2013
Clostridium in whey protein turns out not to be C. botulinum
The Ministry of Primary Industry today made a statement that tests on the Clostridium species isolated from Fonterra whey protein concentrate show that it is not C. botulinum. The organism is C. sporogenes and poses no food poisoning threat.
This will be a huge relief to Fonterra, the New Zealand government and MPI, not to mention hundreds of parents of babies being fed on infant formula. However, the damage to the company's reputation and the Pure New Zealand brand has been massive. Even countries that did not receive any of the affected powder and formulae have banned the import of New Zealand dairy products.
Why has it taken so long to get a definitive answer and why did the company recall the product?
Tests of products that incorporated certain batches of whey protein concentrate showed growth of sulphite reducing clostridia, though the protein concentrate itself was within specification. Further testing of the bacterial isolates suggested that they might be C. botulinum. Because of the severity of the illness that this microorganism can cause, the company withdrew certain batches of whey protein concentrate from the market and advised its customers accordingly.
It is quite difficult to distinguish certain closely related types of bacteria, and this is the case with C. botulinum and C. sporogenes. The bacteria have to be isolated in pure culture, various biochemical tests must be performed, DNA must be extracted and PCR reactions carried out with specific primers. While this sounds easy, and appears to be very rapid if the CSI-type of TV programmes are to be believed, in practice it is very tricky and time consuming. Extracting the DNA from the bacteria without its being degraded by DNAse enzymes is apparently difficult. There are few laboratories in the world capable of carrying out the testing reliably. (This is not a bacterium to be trifled with. When I worked in England for a year at the Food Research Institute in Norwich, only vaccinated people were permitted to go into the botulinum laboratory because of the risk to workers of lethal intoxication). The 'gold standard' test for toxigenic C. botulinum capable of causing the neuroparalysis is the mouse lethality test. This must be performed very precisely, according to an internationally recognised approved procedure and involves specially bred mice of a particular age. The various tests have now been completed, allowing the announcement from MPI today.
Did Fonterra do the right thing in notifying its customers of the potentially hazardous product and recalling the protein concentrate? In my opinion, they did. Certainly, it has caused the company embarrassment and financial loss, but what of the other option - keeping quiet and hoping the problem would go away? The death of even a single baby from botulism would have been far more damaging, and devastating for the parents.
Will things change in the future? Only time will tell what regulatory changes may follow, and new testing requirements are imposed. One thing is sure: occasionally, food manufacturers will make a mistake; equipment will malfunction, or a set of circumstances will come together that result in potentially unsafe food. The entire food industry must strive to reduce the frequency of these incidents to an absolute minimum by close process control, based on appropriate and robust risk assessment and hazard control measures.
This will be a huge relief to Fonterra, the New Zealand government and MPI, not to mention hundreds of parents of babies being fed on infant formula. However, the damage to the company's reputation and the Pure New Zealand brand has been massive. Even countries that did not receive any of the affected powder and formulae have banned the import of New Zealand dairy products.
Why has it taken so long to get a definitive answer and why did the company recall the product?
Tests of products that incorporated certain batches of whey protein concentrate showed growth of sulphite reducing clostridia, though the protein concentrate itself was within specification. Further testing of the bacterial isolates suggested that they might be C. botulinum. Because of the severity of the illness that this microorganism can cause, the company withdrew certain batches of whey protein concentrate from the market and advised its customers accordingly.
It is quite difficult to distinguish certain closely related types of bacteria, and this is the case with C. botulinum and C. sporogenes. The bacteria have to be isolated in pure culture, various biochemical tests must be performed, DNA must be extracted and PCR reactions carried out with specific primers. While this sounds easy, and appears to be very rapid if the CSI-type of TV programmes are to be believed, in practice it is very tricky and time consuming. Extracting the DNA from the bacteria without its being degraded by DNAse enzymes is apparently difficult. There are few laboratories in the world capable of carrying out the testing reliably. (This is not a bacterium to be trifled with. When I worked in England for a year at the Food Research Institute in Norwich, only vaccinated people were permitted to go into the botulinum laboratory because of the risk to workers of lethal intoxication). The 'gold standard' test for toxigenic C. botulinum capable of causing the neuroparalysis is the mouse lethality test. This must be performed very precisely, according to an internationally recognised approved procedure and involves specially bred mice of a particular age. The various tests have now been completed, allowing the announcement from MPI today.
Did Fonterra do the right thing in notifying its customers of the potentially hazardous product and recalling the protein concentrate? In my opinion, they did. Certainly, it has caused the company embarrassment and financial loss, but what of the other option - keeping quiet and hoping the problem would go away? The death of even a single baby from botulism would have been far more damaging, and devastating for the parents.
Will things change in the future? Only time will tell what regulatory changes may follow, and new testing requirements are imposed. One thing is sure: occasionally, food manufacturers will make a mistake; equipment will malfunction, or a set of circumstances will come together that result in potentially unsafe food. The entire food industry must strive to reduce the frequency of these incidents to an absolute minimum by close process control, based on appropriate and robust risk assessment and hazard control measures.
Monday, June 4, 2012
Safe Food in Troubled Times
On 4th September, 2010, Christchurch was violently shaken by a Magnitude 7.1 earthquake. On 22nd February 2011, an M 6.1 shock destroyed much of the city centre and since that time, there have been about 3400 shocks of greater than M 3.
After the February earthquake, I expected to read of food and water related diseases spreading through the population - the water supplies were seriously damaged and sewer pipes were destroyed, while liquefaction of the ground allowed mixing of ground water and sewage to occur. Contamination of water supplies by faecal bacteria and viruses was therefore a serious consideration. People handling food for themselves and others would have to take great care with personal hygiene and cleaning of food preparation areas.
Amazingly, there were no major disease outbreaks.
New Zealand sits on the Pacific Ring of Fire and is sometimes called The Shaky Isles. We are taught to look after ourselves during a shake and to make preparations to look after ourselves in the aftermath. In my rumpus room out back, I have a cache of canned food and bottled water. But how many of us expected the Christchurch earthquakes to go on for so long? My cache would last for only a couple of days. Some people in badly damaged areas had to cook in their gardens on barbeques and open fires for many days.
This set me thinking about security of food supplies after such disasters. I guess that natural disasters are one thing; what must it be like when those waging civil war deliberately set out to destroy infrastructure?
We can expect that help might take a few days to arrive. Local emergency services will be overwhelmed by the number of people requiring assistance and their own degraded response capabilities - roads will be damaged and may be impassable for emergency vehicles. Stores and warehouses may be destroyed, power supplies will be interrupted and food may therefore be scarce, spoiled and possibly contaminated.
The first few days are therefore critical for the population to survive and begin rebuilding their lives. A secure and safe supply of food and water is essential. How does the average family prepare for their own and their neighbours' welfare? Dried and canned foods provide a safe and stable basis for the emergency supply.
There are many websites that will help you plan. Civil Defence in New Zealand provides lots of valuable information, such as lists of things you need in a survival kit; commercial organisations offer ready-made kits and meals that can be prepared with minimal resources.
I don't endorse the following sites or products, but you may find them useful.
A quick search on one of the major search engines will provide you with many more links to valuable information.
If you want more information on the Christchurch earthquakes, see the following:
After the February earthquake, I expected to read of food and water related diseases spreading through the population - the water supplies were seriously damaged and sewer pipes were destroyed, while liquefaction of the ground allowed mixing of ground water and sewage to occur. Contamination of water supplies by faecal bacteria and viruses was therefore a serious consideration. People handling food for themselves and others would have to take great care with personal hygiene and cleaning of food preparation areas.
Amazingly, there were no major disease outbreaks.
New Zealand sits on the Pacific Ring of Fire and is sometimes called The Shaky Isles. We are taught to look after ourselves during a shake and to make preparations to look after ourselves in the aftermath. In my rumpus room out back, I have a cache of canned food and bottled water. But how many of us expected the Christchurch earthquakes to go on for so long? My cache would last for only a couple of days. Some people in badly damaged areas had to cook in their gardens on barbeques and open fires for many days.
This set me thinking about security of food supplies after such disasters. I guess that natural disasters are one thing; what must it be like when those waging civil war deliberately set out to destroy infrastructure?
We can expect that help might take a few days to arrive. Local emergency services will be overwhelmed by the number of people requiring assistance and their own degraded response capabilities - roads will be damaged and may be impassable for emergency vehicles. Stores and warehouses may be destroyed, power supplies will be interrupted and food may therefore be scarce, spoiled and possibly contaminated.
The first few days are therefore critical for the population to survive and begin rebuilding their lives. A secure and safe supply of food and water is essential. How does the average family prepare for their own and their neighbours' welfare? Dried and canned foods provide a safe and stable basis for the emergency supply.
There are many websites that will help you plan. Civil Defence in New Zealand provides lots of valuable information, such as lists of things you need in a survival kit; commercial organisations offer ready-made kits and meals that can be prepared with minimal resources.
I don't endorse the following sites or products, but you may find them useful.
http://www.pcc.govt.nz/A-Z-Services/Emergency-Management/It-s-Easy---Get-prepared/Emergency-Food-Stores
http://www.prepare.co.nz/default.asp?c=11655
http://www.efoodsdirect.com/
http://whatscookingamerica.net/LeaSchneider/EmergencyFoodPantry.htm
http://www.bt.cdc.gov/preparedness/kit/food/
A quick search on one of the major search engines will provide you with many more links to valuable information.
If you want more information on the Christchurch earthquakes, see the following:
http://www.christchurchquakemap.co.nz/
http://www.geonet.org.nz/var/storage/images/media/images/earthquake/aftershock_decay/58870-7-eng-GB/aftershock_decay.png
Wednesday, April 18, 2012
How much does Joe Sixpack know about food safety?
Recently, we ran a small competition for attendees at a public food expo. They had to enter answers to questions on food safety knowledge set by a computer. The machine stored the answers and we drew a prize from those who got them all right. Incidentally, we used this as an educational opportunity by giving immediate feedback on the answers entered.
Though the survey was not statistically valid, I analysed the responses. The results were largely unsurprising - approximately 65 to 75 percent of responses were correct for most questions.
However, a third of respondents didn't know which food poisoning bacterium (Campylobacter) causes the most food poisoning in New Zealand, despite extensive coverage in the news media over the past two years. A third also incorrectly identified pesticide residues as more important than packaging failure in causing human foodborne disease, and again, a third thought that it was illegal to sell food past its "best before" date. Only a quarter of respondents knew that it is legal to sell raw milk in New Zealand.
It was pleasing to see that 97 percent of respondents knew that refrigeration would not stop the growth of all bacteria in food, and 80 percent understood that irradiation is not a means for unscrupulous manufacturers to make spoiled food appear fresh.
Of more concern was the belief by 80 percent of respondents that chicken can be regarded as cooked if the juice runs clear when the thigh meat is pricked, and 28 percent of respondents thought that if it were safe to eat a rare steak, it was also safe to eat hamburger rare.
It seems that we still have some way to go in educating our population about safe food handling and consumption.
Though the survey was not statistically valid, I analysed the responses. The results were largely unsurprising - approximately 65 to 75 percent of responses were correct for most questions.
However, a third of respondents didn't know which food poisoning bacterium (Campylobacter) causes the most food poisoning in New Zealand, despite extensive coverage in the news media over the past two years. A third also incorrectly identified pesticide residues as more important than packaging failure in causing human foodborne disease, and again, a third thought that it was illegal to sell food past its "best before" date. Only a quarter of respondents knew that it is legal to sell raw milk in New Zealand.
It was pleasing to see that 97 percent of respondents knew that refrigeration would not stop the growth of all bacteria in food, and 80 percent understood that irradiation is not a means for unscrupulous manufacturers to make spoiled food appear fresh.
Of more concern was the belief by 80 percent of respondents that chicken can be regarded as cooked if the juice runs clear when the thigh meat is pricked, and 28 percent of respondents thought that if it were safe to eat a rare steak, it was also safe to eat hamburger rare.
It seems that we still have some way to go in educating our population about safe food handling and consumption.
Tuesday, March 20, 2012
Giving bacteria a cold
I hope that title got your attention. I could equally have used "Fight fire with fire" or "Biological warfare".
Food Standards Australia New Zealand is calling for submissions on an application to use viruses to aid in the control of Listeria monocytogenes. L. monocytogenes is a bacterium found in the environment that can infect food and may cause listeriosis. The majority of the population is unaffected by Listeria, but it is a hazard for pregnant women, young children and the elderly, in addition to those who are immunocompromised. Note that you don't have to have had an organ transplant to be immunocompromised - you might just have another infection stressing your immune system.
You might think that deliberately putting viruses into foods is crazy. However, these viruses are special. They exclusively target bacteria and are called bacteriophages. Bacteriophages (or "phages") are extremely common; they occur at levels up to 9×108 per mL in bacterial mats at the surface of the sea. They were first identified in 1915 by Frederick Twort in England and, independently, in 1917 by Felix d'Herelle in France.
Bacteriophages are deceptively simple - essentially a piece of nucleic acid contained within a protein coat called a capsid. They can't reproduce independently and have to have a means of infecting a living cell. Perhaps the most famous phage is the T4 phage that infects Escherichia coli and always reminds me of the lunar lander. (I sometimes wonder how something like this could have evolved by chance). See image from Wikipedia below.
When a phage infects a bacterial cell, it injects its DNA into the cell. The viral nucleic acid then takes over the bacterial synthetic machinery and makes copies of itself, and synthesises new phage coat and other components. The components are then assembled into new phage particles, whereupon the bacterial cell is lysed and releases the phage. Burst sizes may be around 100 viruses per bacterial cell. Since these are all infective, the infection of the population proceeds rapidly, resulting in the death of the majority of the bacterial cells. Phages cause the cheese-making industry a lot of trouble, because they kill the starter bacteria.
The application currently under consideration is for the use of a mixed bacteriophage preparation, sold commercially as LISTEX™ P100, as a processing aid. This preparation was the first phage product to be classified as Generally Recognized as Safe (GRAS) by the FDA and USDA.
A number of scientific papers have been published on the efficacy of the P100 preparation, showing that the phage significantly reduces the population of L. monocytogenes on foods, such as salmon fillets or surface-ripened cheeses*.
The use of bacteriophage to control pathogens, such as Listeria and Salmonella, can reduce the risk of food poisoning, though it is unlikly that it can be a total solution, as the pathogen population may not be totally destroyed. However, when used in an integrated food safety programme, the processing aid can be a valuable tool, reducing the reliance on chemicals to inhibit the bacteria.
* See: doi:10.1016/j.yrtph.2005.08.005
Odd Spot: When I was researching this post, I searched on "Listeria virus". I got many hits, predominantly in popular press and websites, where the Listeria bacteria were described as "viruses". In modern microbiology terms, this is totally wrong. However, "virus" is derived from the Latin word for poison and this apparently appeared in the English lexicon in 1392. "Virus" was also used in 1728 to describe an "agent that causes infectious diseases". I'm sure that most of those press writers didn't know this, but, strictly, they were correct.
Food Standards Australia New Zealand is calling for submissions on an application to use viruses to aid in the control of Listeria monocytogenes. L. monocytogenes is a bacterium found in the environment that can infect food and may cause listeriosis. The majority of the population is unaffected by Listeria, but it is a hazard for pregnant women, young children and the elderly, in addition to those who are immunocompromised. Note that you don't have to have had an organ transplant to be immunocompromised - you might just have another infection stressing your immune system.
You might think that deliberately putting viruses into foods is crazy. However, these viruses are special. They exclusively target bacteria and are called bacteriophages. Bacteriophages (or "phages") are extremely common; they occur at levels up to 9×108 per mL in bacterial mats at the surface of the sea. They were first identified in 1915 by Frederick Twort in England and, independently, in 1917 by Felix d'Herelle in France.
Bacteriophages are deceptively simple - essentially a piece of nucleic acid contained within a protein coat called a capsid. They can't reproduce independently and have to have a means of infecting a living cell. Perhaps the most famous phage is the T4 phage that infects Escherichia coli and always reminds me of the lunar lander. (I sometimes wonder how something like this could have evolved by chance). See image from Wikipedia below.
When a phage infects a bacterial cell, it injects its DNA into the cell. The viral nucleic acid then takes over the bacterial synthetic machinery and makes copies of itself, and synthesises new phage coat and other components. The components are then assembled into new phage particles, whereupon the bacterial cell is lysed and releases the phage. Burst sizes may be around 100 viruses per bacterial cell. Since these are all infective, the infection of the population proceeds rapidly, resulting in the death of the majority of the bacterial cells. Phages cause the cheese-making industry a lot of trouble, because they kill the starter bacteria.
The application currently under consideration is for the use of a mixed bacteriophage preparation, sold commercially as LISTEX™ P100, as a processing aid. This preparation was the first phage product to be classified as Generally Recognized as Safe (GRAS) by the FDA and USDA.
A number of scientific papers have been published on the efficacy of the P100 preparation, showing that the phage significantly reduces the population of L. monocytogenes on foods, such as salmon fillets or surface-ripened cheeses*.
The use of bacteriophage to control pathogens, such as Listeria and Salmonella, can reduce the risk of food poisoning, though it is unlikly that it can be a total solution, as the pathogen population may not be totally destroyed. However, when used in an integrated food safety programme, the processing aid can be a valuable tool, reducing the reliance on chemicals to inhibit the bacteria.
* See: doi:10.1016/j.yrtph.2005.08.005
Electron micrograph of T4 phage adsorbed to a bacterial cell.
Image by Elizabeth Kutter, Bacteriophage Ecology Group
http://www.mansfield.ohio-state.edu/~sabedon/beg_phage_images.htm
Odd Spot: When I was researching this post, I searched on "Listeria virus". I got many hits, predominantly in popular press and websites, where the Listeria bacteria were described as "viruses". In modern microbiology terms, this is totally wrong. However, "virus" is derived from the Latin word for poison and this apparently appeared in the English lexicon in 1392. "Virus" was also used in 1728 to describe an "agent that causes infectious diseases". I'm sure that most of those press writers didn't know this, but, strictly, they were correct.
Tuesday, January 24, 2012
Want to know more about the origin of Shigatoxin-producing E. coli?
Bill Marler is a very rare individual: he is a lawyer with an ability to grasp the principles of microbiological food safety and to write about them in a way that is accessible to the general public. Bill has been closely involved in food borne illness litigation since 1993, when he obtained a $15.6 million settlement for Brianne Kiner, a nine year old girl who suffered HUS and ultimately kidney, liver and pancreas failure after eating Jack-in-the-Box hamburger. He has become a fiercely active food safety campaigner.
Recently, Bill conducted a literature review on the origins of Shigatoxin-producing Escherichia coli and has published the first two parts on his food safety blog. These publications are well worth reading - they are not written in highly technical language, but the reference list allows those readers sufficiently interested and capable to follow up his sources and read the original material.
Links to the first two parts are shown below:
There is just one problem with this review; Bill has taken away my option to set such a study of literature as an assignment for my postgraduate students in my course "Frontiers of Food Microbiology". The students will still be expected to read and discuss the material, but I can't use their reviews for assessment purposes. Thanks Bill!
Recently, Bill conducted a literature review on the origins of Shigatoxin-producing Escherichia coli and has published the first two parts on his food safety blog. These publications are well worth reading - they are not written in highly technical language, but the reference list allows those readers sufficiently interested and capable to follow up his sources and read the original material.
Links to the first two parts are shown below:
There is just one problem with this review; Bill has taken away my option to set such a study of literature as an assignment for my postgraduate students in my course "Frontiers of Food Microbiology". The students will still be expected to read and discuss the material, but I can't use their reviews for assessment purposes. Thanks Bill!
Tuesday, October 11, 2011
Food Safe Families: Does it Prevent Contamination of Foods? Guest Editorial
Patricia Walling*
In just about any news medium, headlines about recalls of meat, poultry and produce due to contamination occur with deadly regularity. Sadly as anyone in health care knows these headlines aren't just hype; food borne diseases can be fatal. This is especially true when they infect the very young, elderly and those with compromised immune systems.
According to the Center for Disease Control and Prevention (CDC) “each year, 1 in 6 Americans, or 48 million people get sick, 128,000 are hospitalized and 3,000 die of food borne diseases.” The agency notes that among the 31 known food borne pathogens, the leading causes of deaths and hospitalization are: Salmonella, Toxoplasma, Listeria, norovirus and Campylobacter.
Based on this public health problem, a partnership was formed among several U.S. governmental agencies (including the U.S. Department of Agriculture, the Department of Health and Human Services, the Food Safety and Inspection Service, Food and Drug Administration and the CDC) that are charged with keeping the food sources safe in conjunction with the Ad Council. The campaign, recently announced by the USDA, is titled “Food Safe Families.”
These organizations feel that this promotional effort will “shift the way people think about food handling so they can take a more proactive approach at home to help reduce food-related illnesses.” However, not everyone feels this educational and health promotion campaign will do much to solve the real challenges of the food distribution system.
The Food Safe Families Program
Public service campaigns, created by U.S. governmental agencies have a storied history. From the iconic U.S. Forest Service and Ad Council campaign that featured Smokey Bear admonishing that: “Only you can prevent forest fires” (launched in 1947), to the FDA’s “Food Pyramid” (first launched in 1992, updated in 2005 and then replaced in 2011), there have been hundreds of public service campaigns that are well-meaning but often ineffective.
Will the Food Safe Families campaign have the promotional “legs” of Smokey Bear’s message or join “Just Say No” campaign as a waste of taxpayer money? Only time will tell. However, the campaign includes several aspects that make it important.
According to the USDA Food Blog, “using the motto “Check Your Steps,” Food Safe Families aims to get consumers to adopt four very easy steps when preparing food:
1. Clean: Clean kitchen surfaces, utensils and hands with soap and water when preparing food.
2. Separate: Separate raw meats from other foods by using different cutting boards.
3. Cook: Cook foods to the right temperature by using a food thermometer.
4. Chill: Chill raw and prepared foods promptly.”
These four steps – clean, separate, cook and chill – serve as the graphic and messaging platform of the campaign. The agencies hope that by constantly reiterating this message, it will become ingrained in those who are charged with preparing the family meals.
Even the timing of the launch was important. The agencies choose Jun. 28, 2011, because this is the start of summer and represents the prime outdoor grilling season for most families. The USDA noted in its blog that “food borne illnesses tend increase with more outdoor meals.”
Once the campaign was launched, it seemed that Food Safe Families had covered most of the promotional bases. There were spiffy new graphics, memorable message points, an innovative social media campaign and public service media all up and running. The timing and execution of the campaign was excellent, until people started showing up in emergency rooms with symptoms of Listeriosis.
The Listeria Outbreak
Jensen Farms, located in Holly, Colorado grows and ships cantaloupes throughout the United States. After numerous reports of an outbreak of Listeriosis, the FDA and CDC traced the contaminated melons back to this farm. According to a news update from the FDA on Sept. 30, 2011, “the cantaloupes were produced from the end of July to Sept. 10, 2011. Given that the Jensen Farms’ recall has been in effect for more than two weeks, it is expected that all of the recalled whole Jensen Farms cantaloupes have been removed from the marketplace.”
The website for the Mayo Clinic notes that “Listeria infection is a food-borne illness that can be very serious for pregnant women and people with impaired immune systems. Listeria bacteria can survive refrigeration and even freezing.” As of Oct. 1, 2011, the CDC reported that the contamination had been responsible for the deaths of 17 people and the illness of 84 across 19 states.
In response to this outbreak, the FDA noted that “It is very important that consumers clean their refrigerators and other food preparation surfaces. Consumers should follow these simple steps:
• Wash hands with warm water and soap for at least 20 seconds before and after handling food.
• Wash the inside walls and shelves of the refrigerator, as well as cutting boards and countertops.
• Wipe up spills in the refrigerator immediately and clean the refrigerator regularly.
• Always wash hands with warm water and soap following the cleaning and sanitization process.”
Do These Guidelines Prevent Food Borne Illness?
For all of the regulations, safeguards, inspections and, yes, public service campaigns, the growers and processors of food employ humans and sometimes they get careless and make mistakes. Such is also the case with homemakers.
In cases where these mistakes cause deadly diseases to spread, the Food Safe Families campaign could help to ameliorate the damages from contaminated cantaloupes, ground meat, peanut butter or any other food. However, it will have no effect on preventing the disease from starting. That involves many other factors. These include: the distance and the number of companies that must handle food between the farm and family and the quantity and quality of the inspections along the distribution channels.
Given time, the Food Safe Families campaign could have a positive impact on the health of U.S. citizens. Even now, the use of the social networks that were launched for this campaign have served as valuable tools to help with the dissemination of information about the latest contamination. However, such programs as buying foods that are produced closer to home may have more impact.
* Patricia Walling
Patricia Walling is a web content designer for several healthcare-related sites. She self-identifies as a perpetual student of medicine, and can be found most of the time researching anything
related to the field. She lives in Washington, and as a result loves the long winters.
related to the field. She lives in Washington, and as a result loves the long winters.
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