Hepatitis E in Pork

There is usually one food scare or another in the media to keep us on our toes and, after the furore over horse meat found in some products had died down, the latest to hit the front pages is the risk of Hepatitis E in pork. This story broke last week in the papers but it is not news to everybody.  Several studies have already been carried out to investigate these reports and the findings are interesting.

Hepatitis E (HEV) is a virus that affects the liver and the main symptoms include jaundice, pale stools and darker than normal colouration of urine.  The good news is that it is a virus the body’s natural defence system can deal with and it usually resolves itself fairly quickly.  Some cases can be more serious for those with pre-existing immune conditions or pregnant women, so it is always advisable to see a doctor.

In countries where sanitation is poor, it is most commonly transmitted through water and food contaminated with sewage from infected people and animals.  In other countries, it can be spread from animals to humans, mostly through undercooked pork and sometimes processed pork.  HEV is widely found in pigs, hence the suspected risk.  It is highly unusual for humans to contract it from another human.

In recent years, there has been a significant rise in cases of HEV in a number of developed countries, including Japan, France, the Netherlands, the US and the UK.  Those mostly affected tend to be men over the age of 50.  A study was carried out in 2009-10 by the Animal Health and Veterinary Laboratories Agency in Weybridge that found there was evidence that the virus was potentially passed on during pork production.  They collected samples from slaughtered pigs at various points of manufacture, right through to the final product which lands on our shelves.  As a rule, the percentage of the virus found in samples of point of sale items was low, but it was discovered.  Of 63 sausages tested, 6 were found to contain the virus.

A later study in 2013, initiated by Defra and backed by other public bodies including the Food Standards Agency and Public Health England, concluded that, of the approximately 60,000 human cases of HEV in the UK each year, two thirds in England were NOT transmitted from UK pig products.

What does this mean for us?  It is apparent there is a very small risk that some point of sale pork products could contain HEV, however, most products you buy at the supermarket will be safe.   Make sure you buy your pork products from a trusted source.  All good suppliers will only purchase meat from approved outlets and abattoirs with robust HACCP and food safety management systems in place.  Since these studies were carried out, it is likely that even more stringent procedures will have been implemented by any good manufacturer.

The Food Standards Agency advises that, when cooking pork, it should be ‘thoroughly cooked until steaming hot throughout, the meat is no longer pink and the juices run clear.’  This will minimise any risk of any foodborne illness, not just HEV.

Finally, if we even need to say it, always remember to wash your hands thoroughly before and after preparing pork and clean and disinfect the equipment and utensils used thoroughly to avoid cross contamination!

 

What is HPP?

There’s really nothing nicer than fresh produce to get the maximum enjoyment of flavour and texture but, for most of us, cooking and eating fresh produce every day isn’t always possible.  Many of our eating habits are dictated by time constraints imposed by our busy lifestyles, leaving little opportunity for daily visits to the supermarket for fresh items with which to prepare our meals.

Fresh products will spoil fairly quickly as any bacteria present in food multiplies and makes the food unfit for consumption.  Some bacteria are beneficial to us, such as those present in yoghurts, but others can cause illness and are known as pathogens.  It is these pathogens that pose a threat to our health when they multiply in foods; defiling them and rendering them unsafe to eat.  Other types of bacteria will simply cause the food to spoil and perish, making it inedible.

Therefore, the tendency is often to rely on foods which have been preserved by one method or another that we can keep in our fridge longer than just a few days.  Some of the most common ways of food preservation include adding chemicals to stop the bacteria from growing, high heat or thermo treatments and dehydration.  All these options are effective but can bring with them a depreciation in taste and texture and often a loss of nutrients.

The food industry is always looking for ways to improve and a relatively new method of preserving products called high pressure processing (HPP) is gradually gaining a foothold in the trade as awareness of its benefits increases.  Interestingly, the knowledge of this process has been around since the 19th century, but it has only really been developed to greater potential in the last twenty years.

HPP is a method which uses high pressure to pasteurise foods, making bacteria inactive.  Unlike most other methods, it pasteurises the food once it is sealed and in its final packaging.  It works by passing food items through an industrial container which is then filled with cold water and the pressure increased to about 6000 bars.  This is equivalent to the pressure of being at least five times deeper than the deepest point of the deepest ocean.  ThyssenKrupp, a company which specialises in HPP and high pressure technologies compares this to, ‘the weight of three jumbo jets acting on an area the size of a smartphone’.  This pressure is what makes the microorganisms inactive and the food safe.  However, it is worth mentioning that the degree of microbiological inactivation will be affected by things like the pH, water activity and protein and sugar content of the product itself.

Its trump card is that it requires no heat and no chemicals so the food can retain its flavours, nutrients and texture.  Another big advantage is that as the product is in its final packaging, any risk of recontamination, which is possible with other methods, is massively reduced.  In a progressively more demanding market, this is good news for consumers and for food suppliers who want to ensure their products are as safe as possible.

The process can only be used if the item is vacuum packed and sealed in flexible packaging or in a plastic bottle so it does have its restrictions.  A glass container, for example, would be obliterated under the pressure so, at present, HPP is regarded as an alternative to other thermo methods and companies use it mostly for fruit juices and smoothies but it is developing quickly.

In a world where food waste is an increasingly big issue with millions of tons being thrown away each year, HPP is great news.  Companies claim that the process can extend shelf life by up to 10 times the normal length.  Items are safer for longer whilst still maintaining much of their original freshness, flavour and nutrients, resulting in overall food wastage being reduced.  This can only be a good thing for the food industry and, as HPP continues to be advanced, things can only get better.

 

What is Acrylamide?

We’ve all done it. We’ve popped the bread in the toaster and gone away and forgotten about it. The next thing we know, the smoke alarm’s going off and our toast resembles a lump of charcoal. Some of us will consign it to the dustbin, but others adhere to the old adage, waste not want not, and continue to consume it, attempting to overcome the burnt flavour with lashings of their favoured topping.

For years, there have been rumours circulating that burnt toast is carcinogenic but, realistically, is there any evidence for this?

Studies have shown that a chemical called acrylamide is formed naturally when starchy foods are cooked at high temperatures (anything above 120˚C). Food items that this applies to are potatoes in various forms, e.g. roast, chips, crisps etc., bread and some cereal products. The sugars in the foods react with naturally occurring amino acids when exposed to high temperatures to form acrylamide.

Scientists tested the impact of acrylamide on rodents and it was found that exposure to the chemical increased the risk of developing several types of cancer quite significantly. As a consequence of these results, food scientists are concerned that this evidence indicates there is a potential cancer risk to humans. There are a few caveats to this, however. It should be noted that the rodents were subjected to exceptionally large doses of the chemical, doses which would be far greater than any amount contained in your Sunday roast potatoes or a bag of crisps, for example. Studies in humans are still incomplete and are, at present, inconclusive. It is impossible to say that a chemical will affect animals and humans in exactly the same way so the results must be considered rationally and cautiously, but it is sensible to pay attention to the scientific findings and take some precautions.

This year, the Food Standards Agency has launched a campaign called, ‘Go for gold’. Contrary to how it might sound, they are not encouraging people to enter the Olympics, but have issued guidelines on how to attain the optimum shade of gold when cooking your starchy foods. With any form of cooking, whether it be frying, roasting or toasting, the goal should be to achieve a light golden colour. Cooking starchy food for too long and at too high a temperature will increase the amount of acrylamide. They also advise against keeping potatoes in the fridge as this can cause the sugars to multiply, thus raising the amount of acrylamide in the end product once cooked. Always check the guidelines on the packet when cooking things like oven chips. The food industry is attempting to do what it can to reduce the acrylamide concentrations in food so it would be prudent to follow their cooking guidelines.

It is easy to be alarmed by these reports about such staple fixtures of our diets, but it is important to remember that the studies on humans are inconclusive and that the risk is not yet substantiated. The Food Standards Agency recommends that a balanced and moderate diet including your standard 5 a day will help reduce the risk of cancer. Let moderation be our watchword and maybe that piece of toast really should just go in the bin.

 

Here is a video from the Food Standards Agency with some basic information on Acrylamide and their ‘Go for Gold’ Campaign.