Food Hygiene Essentials

A few weeks ago a leading Israeli fruit juice manufacturing plant had several hundred tons of water melon concentrate condemned by the ministry of heath on the pretext that there were unacceptable contaminants within the juice.

The concentrate in question was destined for use on the home market where it is used by the ice cream and iced lollie factories to manufacture a popular range of water melon flavored products. This set back has put additional pressure on a market sector which is already struggling to survive the current market recession.

Israel has suffered several consecutive years of very low rainfall. The sea of Galilee which is the major fresh water reservoir for Israel and it’s neighbours has reached dangerously low levels and as a result of this crisis water prices have risen several fold. As a result of this new state of affairs the profit margins in which vegetable and fruit growers operate have been cut even further and it is really uncertain from year to year if it will be worth growing anything at all.

The jordan valley which enjoys a milder winter than many other parts of Israel is famous for producing early fruit and vegetable harvests both for the home and export markets.

Seemingly, some of the areas water melon growers took it upon themselves to irrigate this years water melon harvest that was intended for industry with grey water instead od fresh water. The logic behind this decision being that grey water does not contain more contaminants than those already presant in ordinary soil.

What is not clear is if the water used for irrigation was indeed just grey water or if the suppliers of the grey water added certain quantities of first stage black water filtrate to the grey water that was being supplied to the farmers. It is also possible that the farmers used grey water for the initial stages of germination and consequent stages before the development of the water melon itself, switching over to fresh water once the melon began to develop. In any case, whatever the sequence of events was, contaminants entered the melons.

Samples of the water melon concentrate were tested both for chemical and microbial contaminants and found to test positive for both categories of contaminates within the concentrate. the concentrate was deemed to be a risk to public health and presented a food hygiene problem. The water melon concentrate was condemned and will not be used to make the iced products that it was intended to make.

The case is being looked into more closely by the public prosecutors office and charges are expected to be issued to those responsible for taking these regretable discisions to used contaminated water for growing water melons.

What is listeriosis?
Listeriosis is a bacterial infection caused by the bacterium Listeria monocytogenes. Until several years ago it was thought that this bacteria only infected animals but it is now accepted that humans are also at risk from this disease. While many bacteria are generally seen to infect specific locations within the human body, Listeria may infect many different locations, such as the brain or the spinal cord membranes or the bloodstream.

Classification:
L. monocytogenes is a gram positive, non-spore forming, motile, facultatively anaerobic, rod shaped bacterium. It is catalase positive, oxidase negative, and expresses a Beta hemolysin which causes destruction of red blood cells. This bacterium exhibits characteristic tumbling motility when viewed with light microscopy. [6] Although L. monocytogenes is actively motile by means of peritrichous flagella at room temperature (20-25C), the organism does not synthesize flagella at body temperatures (37C). [7]

Who gets listeriosis?
Anyone can get this disease, but those at highest risk for serious illness from this bacterium are newborns, the elderly, people with weakened immune systems, and pregnant women. Healthy adults and children occasionally get infected with Listeria, but they rarely become seriously ill. Listeria Monocytogenes is classified as an intracellular paracite. This means that it invades and lives within cells of the body thereby managing to evade the body’s immune system. Infection by as few as 1000 individual bacteria is considered enough for the disease to take hold. When listeric meningitis occurs, the overall mortality may reach 70%; from septicemia 50%, from perinatal/neonatal infections greater than 80%. In infections during pregnancy, the mother usually survives.

When do Listeria infections occur?
Infections occur throughout the year. Although most cases occur sporadically, food-borne outbreaks of this disease do frequently occur. Poor food hygiene and poor personal hygiene conditions are responsible for many of the recently recorded outbrakes.

How is listeriosis spread?
Listeria bacteria are widely distributed in nature and can be found both in water and soil. Infected animals may also serve as sources of contamination. Unlike other organisms, Listeria can be spread through several different methods. Ingestion or food-borne transmission of the organism, such as through the ingestion of unpasteurized milk or by the eating of contaminated vegetables, is often a source of many cases. In newborn infections, the organism can be transmitted from mother to fetus in utero, or directly to the fetus at the time of birth through the contact of the fetus’ blood supply with that of the mothers. Direct contact with the organism can cause lesions on the skin.

What are the symptoms of listeriosis?
Because listeriosis can affect many different parts of the body, the symptoms vary. For meningoencephalitis, the onset can be sudden with fever, intense headache, nausea, vomiting and signs of meningeal irritation. In other body locations, various types of lesions at the site of infection are the primary symptom. In most cases, Listeria infection causes fever and influenza-like symptoms resembling a host of other illnesses.

How soon after exposure do symptoms of listeriosis appear?
Listeriosis has an extremely variable incubation period. It can range from 3 to seventy days, but symptoms usually will typically appear within a month of infection.

How is listeriosis diagnosed?
Specific laboratory tests are the only way to effectively identify this disease. Since many cases may be mild, the disease may be much more common than is realized.

Are there any unusual features of listeriosis?
Listeria infections are a significant risk for pregnant women, who may not experience obvious symptoms. Infection of the fetus can occur before delivery and can cause abortion as early as the second month of pregnancy, but more often in the fifth and six months. An infection later in pregnancy may cause exposure during birth, sometimes resulting in infection of the newborn child which may be fatal.

Does past infection with Listeria make a person immune?
Past infection does not appear to produce immunity.

What is the treatment for Listeria infection?
Several antibiotics are effective against this organism. Ampicillin, either on it’s own or in combination with other types of antibiotics, is frequently used.

What can be done to prevent the spread of Listeriosis?
Since the organism is widly distributed throughout nature, basic sanitary measures such as only using pasteurized dairy products, by only eating cooked meats and washing hands thoroughly prior to the preparation of foods offer the best protection against infection by this disease.

In addition, the following recommendations are for persons who are categorized to be at high risk of infection, such as pregnant women, the elderly and persons with compromised immune systems:

Do not eat hot dogs, luncheon meats, or deli meats, unless they are reheated until they are steaming hot.
Avoid getting the liquid from hot dog packages onto other foods sources, utensils, and food preparation surfaces, and remember to wash hands after handling hot dogs, luncheon meats, and deli meats.
Do not eat soft cheese products such as feta, Brie, and Camembert, blue-veined cheeses, or Mexican-style cheeses such as queso blanco, queso fresco, and Panela, unless they clearly state they are made from pasteurized milk written on the labelling of the product.
Do not eat chilled pâtés or meat spreads. Canned or shelf-stable pâtés and meat spreads can be eaten.
Do not eat refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole. Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna or mackerel, is most often labeled as “nova-style,” “lox,” “kippered,” “smoked,” or “jerky.” The fish is found in the refrigerator section or sold over deli counters of grocery stores and delicatessens and supermarkets. Canned or shelf-stable smoked seafood may be eaten.

E. Coli or escherichia coli are gram negative, rod shaped, motile or non motile, non spore producing facultative anaerobic bacteria which live in the lower intestine of all warm blooded animals. E. Coli species that are capable of propulsion do so by means of a ‘flagella’ which is a whip like tail.

Most types of e. coli are absolutely harmless and are part of the normal and necessary flora of warm blooded species. In fact they are very necessary because they produce vitamin K as a bi product of their metabolic activity and by existing in great numbers help by preventing other pathogenic bacteria from colonizing the gut.

Some species of e.coli are pathogenic which means that they can cause desease. The strains that are pathogenic are 0157:H7 and 0111:B4. This particularly virulent capacity was transferred to these e.coli bacteria from shigella bacteria which passed shiga toxin to e.coli by means of bacteriofages which are a type of viral species. Both these strains of e.coli have the capability of transferring their virulent qualities to other bacteria around them by means of their sex pilus which is a needle like protrusion from the side of their body wall by which they insert the DNA codes necessary for the production of virulent qualities into bacteria next to them. One such virulent quality is the ability to resist certain anti biotics.

The very virulent strains of coli such as 0157:H7 and 0111:B4 are capable of causing serious intestinal illness particularly in the very young, old and the immunologically compromised. However it must be stressed that the majority of common e.coli outbreaks are mild and cause only diarrhea and mild temperature increase. More serious virulent cases can cause complications such as hemolytic-uremic syndrome.

E. coli toxins can be heat tolerant or heat labile. This quality makes the boiling of water to kill e. coli unsure and in such a case water should be boiled in a pressure cooker, if available, for at least twenty minutes. Another alternative would be to only drink safe bottled water if possible. E. coli bacteria which escape from the intestine into the abdominal cavity through means of a perforated ulcer, intestinal lesion or a ruptured appendix will cause peritonitis and be life threatening if not treated promptly with antibiotics such as streptomycin and gentamycin to which e.coli are very sensitive. E. Coli which are associated with the intestinal mucosa lawyer can be found in greater numbers in conditions such as Crohns disease, iritable bowel disorder and ulcerative colitis.

E.coli is contracted through contact with contaminated food or water sources in which the content of the gut as come into direct or ‘indirect’ contact with food or water. Severe cases of e. Coli infection can resemble cholera.

New strains of E.coli are continually being produced by the process of mutation. Some strains may develop traits that are harmful to the host animal. E.coli prefers to reproduce at the temperature of 37 degrees Celsius but some strains have shown the capacity to reproduce at temperatures of up to 49 degrees Celsius.

E. coli has been found in agricultural produce such as spinach. In 2006 there was a famous outbreak of contaminated spinachin the US due to the fact that bovine feces polluted a spinach field which was at the bottom of the hill on which a herd of cattle were kept. In this case all the spinach was recalled and destroyed.

E. coli contamination can be prevented for the most part by maintaining a correct food hygiene policy in the kitchen and by using reputable food suppliers.

One of the great passtimes of all time has to be the camping holiday. So many of us work at the same old job day in and day out going through the same old routines time and time again. We long for the day when we can hang up that apron, pack everything we need into a back pack and head out onto the open road. At least some of us do.

Camping holidays vary greatly. To some camping may be sleeping rough next to the camp fire with only the stars for a roof. To others camping may be a luxury safari in Kenya where everything is maticulously planned right down to the champagne on ice and after eight mint on the pillow. Whatever our dream camping holiday may be, we should remember that we are no longer in our natural environment. We can no longer say that we are entirely suited to living out in the open. The days when our distant ancestors were hunter gatherers are long gone and the level of natural immunity that they possessed we can only wish for.

When we are in an outdoor environment for an extended period of time we need to keep in mind that we take care of all of our needs in the same environment whereas in our homes we have created separate environments to cater for our various needs. When we are in the outdoor environment we actually have very limited control over it. The quality of water in a natural environment is what it is. We can do nothing to change it nor can we do much to deter insect vectors such as flies, ants, ticks and leeches, for example.

The only way we can control the effect that the environment has on us is to control the way we organize ourselves within it. The most important logistical problem that we face from a food hygiene aspect is the problem of water. We must have a safe source of water. The second most important problem that we face is having safe food to eat and the third most important problem that we have to contend with is how to take care of our personal hygiene needs without contaminating the area in which we have to live. Ideally these should be three separate areas. This will reduce the risks of cross contamination.

On a camping trip we may have only one source of water which we have to use for purposes of hygiene, cooking and drinking. This presents a challenge which needs to be addressed. Indeed, a great many cases of serious food and water poisoning originate on camping trips. I can vouch for this personally.

The four golden rule of food hygiene apply as much outdoors as they do indoors. Lets take a look at the four rules and see how to apply them successfully in the camp site scenario.

Rule 1. Buy food from a safe source.
In the camp site this means take food that will not perish. Sterilized packs of food can be bought in specialist outdoors shops which are identical to those used by special forces. Failing that take dried foods and foods that have been packed in small tin cans, tubes, concentrates etc. Avoid taking fresh meats and fish at all costs. Even cooked meat will have a very limited life and can only be taken into account as a packed lunch for the first day to be eaten within four hours of setting off. Fruit such as apples can be taken for several days provided they are washed properly, dried and wrapped in a plastic bag in individual portions. Eggs should be avoided also unless you can get them fresh on your trip. Boil them for no less than 10 minutes. Likewise some hard vegetables such as carrots can be taken for the first couple of days. Again it is best to peel them, wash them thoroughly, dry them and wrap them hermetically in a plastic bag. Do not eat local food on trips unless you are absolutely sure that the source is safe. If you are unsure about a water source it is better to drink fresh milk than drink the water. If you catch dysentery you may well loose more water than you can intake.

Rule 2.Prevent bacteria from entering your food.
Again, by having your food closed in hermetically sealed wrapping the possibility of contamination is greatly reduced. Do not open more than you need for each meal. Do not mix food which has been opened with closed food. Do not leave food for long periods unattended. Either eat it or cook it. Preferably cook it. When handling foods make sure that you are clean, particularly hands and nails. Do not use knives that have been used for any other purpose other than for food. Clean them thoroughly before use as well as after use. Likewise, clean your bowls, plates, cups, knives and forks before eating and drinking as well as directly after the meal. Once clean I recommend putting them into a clean plastic bag to avoid contamination while on the trail. Use only clean water for cooking. If you are unsure of the water source and you have no other use a camp carbon filtration system or use chlorine water purification tablets. The water won’t taste great but it will make it drinkable provided there are no chemical contaminates in it.

Rule 3. Prevent the multiplication of bacteria in your food.
As you may have no way of keeping your cold food at a correct cold temperature it is always wise to eat all your food hot. Don’t leave food laying around. If your food source is all but sterile to begin with you won’t have many worries about the multiplication of bacteria in your food. The secret is to open it and eat it or heat it up and eat it as soon as possible. By that I mean within twenty minutes of being cooked. With a bit of correct organization and compromise on five star cuisine one can all but eliminate this stage.

Rule 4. Destroy bacteria on utensils and work surfaces.
Once again prior organization is the order of the day. Always take some washing up liquid and Lysol or dettol hygiene spray or wipes. Wash all work surfaces thoroughly with soap and rinse with water followed by spraying it with Lysol spray or wiping with an anti bacterial wipe. Do this before and after use. As previously stated wash all eating utensils before and after use. After use spray or wipe with an anti bacterial product and wrap in a clean plastic bag. Seal it as hermetically as possible. Discard the plastic bag after opening it for the next use. Old wrapping should be collected in a trash bag and taken home with you.

Keep your dirty clothing as far away as possible from your eating utensils and food. Make a field toilet at least fifty paces away from your camp site. Even if this is a hole in the ground make sure that you cover your excretions with some of the soil or sand that you have dug from the hole. If you have it pour a little chemical sanitizer onto the soil to deter flies. Avoid camping where others have defecated in the open. Scour the area before choosing the location. Do not wash and brush your teeth in the same area that you go to the toilet or eat. Choose a place suitable for this. If you cant wash as well as you would like use hygienic wipes. Particularly use them after washing your hands after visiting the toilet.

Many people like to entertain the notion that one is allowed to be a bit more lax on a camping holiday. This is the pitfall that causes so many people to fall terribly ill when camping. Nothing could be further from the truth. A healthy and successful camping trip requires quite a high level of forethought, prior organization and planning and an appropriate level of self discipline without ruining the holiday by being overly fanatical and obsessive. This is not what I am advocating. If performed systematically all of my suggestions should take no more than a few minutes of your time around mealtimes and safeguard you against several unpleasant days in hospital and a lifetime’s bad memory.

Most of us in the western world think of dysentery or “Shigella” as a disease of the summer months. Have you ever thought why? Firstly, is it true? Is dysentery a disease of the summer months?

Ok, now I’m going to confuse you a little more because the answer is yes and no. No because dysentery is not only a disease of the summer months and yes because it is mostly proliferated throughout the western world during the summer months, but why?

Dysentery is a disease that is spread via contaminated food and water. A lot of our summer produce is picked in warmer regions of the world where the water sourses osed to irrigate and to wash produce before packing may not be of the best quality and may contain many contaminants. In addition, workers who pick and pack produce may be carriers of certain types of dysentery causing bacteria.

Another major cause of dysentery during summer months for westerner’s is travelling to warmer climates. Whereas locals in many areas of the world may have developed immunities to many bacterial and protozoic species, all of these may be new for us. By being tempted to eat as the locals do we are often exposing ourselves to sources of food and water contamination.

Dysentery is caused by several major causes lets have a look at a couple of them.

Bacterial Dysentery. Bacterial dysentery is caused primarily by the bacterium Shigella dysenteriae. The disease it causes is called shigellosis. This bacterium is a gram negative, non motile, rod shaped, non spore forming facultative anaerobic species that produces a toxin called shiga toxin which is what causes the reaction which we know as dysentery.

Allow me to translate that mouthful of scientific jargon for you. Firstly Gram testing is a form of bacterial staining devised by a man called Mr. Gram which adheres to proteinous outer shells but not to fatty shells. As the vast majority of gram negative bacteria have a Lipopolysaccharide outer shell the dye will not stick, therefore the bacteria are classified as gram negative. Non motile means that they have no mechanism by which they can propel themselves within the medium they are in. Non spore forming means that the bacterium does not have the capability of reducing it’s structural size to permit it to survive periods when conditions are not suitable for bacterial growth, hibernating in short. Facultative anaerobic means that it can live in an oxygen rich environment or in one which is void of oxygen. It is usually when in the anaerobic phase that facultative bacteria will produce their toxins.

The symptoms of dysentery are high fever, vomiting, diarrhea, severe dehydration. Shega toxin is a potentially deadly toxin. Patients with dysentery may experience projectile diarrhoea and projectile vomiting simmultaneously. This is a very unpleasant condition which I have experienced personally. With this disease fluid intake is vital even if that means via infusion and a strict hygiene regeme is vital to rule out the possibility of re infection. Recovery usually takes anything between one to two weeks but in many areas of the world high mortality is common due to improper conditions with which to treat this condition. Mortality rate is particularly high in children and the elderly.

Amoebic Dysentery. This form of dysentery is also spread by the ingestion of contaminated food and water. It is caused by a cyst forming amoebic species. The disease is called intestinal amoebiasis.

This disease is most common in the developing world but not only. One case was reported in St. Petersburg which is quite close to the artic circle. Both bacterial and Ameobic Dysentery are prevelant in developing countries and often get confused. Most cases of travellers dysentary are in fact bacterial or viral in origin. Amoebic dysentery is a parasitical disorder and will not be effected by antibiotics. This form of dysentery may cause infection and enlargening of the liver and blood in stools. Other symptoms remain very much the same as in bacterial dysentery. Metronidazole is the preferred treatment for Amoebic Dysentaty.

Note. Not all species of amoebae are cyst forming.