Learning Resource. Babcock International Group. Food Safety - Hazards and Controls

Transcription

1 Babcock International Group Learning Resource Food Safety - Hazards and Controls It is important to protect food from risk of contamination to prevent food poisoning and the entry of foreign objects. There are three main ways in which food can become contaminated: 1. Microbiological Contamination Includes, pathogenic bacteria, spoilage bacteria, moulds, yeasts and viruses. 2. Physical Contamination Includes, glass, nuts, bolts, hair, insects and jewellery. 3. Chemical Contamination Includes, cleaning materials, pesticides, insecticides and veterinary residues. A fourth type of contamination is; Allergenic Contamination The transfer of allergens which may cause some people to have adverse reactions. 1

2 MICROBIOLOGICAL CONTAMINATION Bacteria are responsible for most food poisoning cases, if food is consumed that has been contaminated by certain, harmful bacteria (pathogenic bacteria) or their toxins (poisons produced by some of these bacteria), food poisoning may result. In general, the bacteria must grow in the food to produce sufficient numbers to infect the body, multiply within the intestine and cause illness. Alternatively, toxins may be produced in the foodstuff or within the intestine, to produce symptoms very soon after ingestion. It is important to remember that foods contaminated with pathogenic bacteria will look, taste and smell perfectly normal. Steps must therefore be taken to prevent pathogenic bacteria getting onto food and multiplying to levels that will cause food poisoning. Sources of bacterial contamination include: Raw foods Such as meat, shellfi sh, vegetables and eggs carry bacteria which may include pathogenic bacteria that will enter your work place on delivery of these items. Raw meat and poultry may be contaminated with Salmonella, Campylobacter and E. coli 0157 that commonly spreads from the animals intestines to the carcass during the slaughtering process. The skin of poultry carries a high number of bacteria, bruises also harbour a large number of bacteria which may be Staphylococci. Shellfi sh may be contaminated with food poisoning organisms, especially bivalves such as cockles, mussels and oysters grown in sewage polluted waters. Vegetables and salad items may be contaminated with pesticides, insecticides or have been irrigated with sewage-polluted water. Egg shells which are dirty may be contaminated with Salmonella. Most food poisoning outbreaks involving hens eggs have involved dishes containing raw egg. People Including food handlers, contractors, delivery personnel and visitors can contaminate food. All people carry food poisoning organisms (Staphylococcus aureus) in the nose, mouth, intestines and also on the skin. Carelessness, poor personal hygiene practices and failure to wear suitable protective clothing can all lead to contamination. Untreated water supplies and poor drainage systems Pollution of water is usually caused by human sewage or faecal contamination from animals. Pathogenic organisms such as Salmonella, Giardia intestinalis and Cryptosporidium spp. can all be transported in water and bacterial spores may survive for several months. Poor drainage can lead to blockage, leakage and fl ooding which will spread bacteria. Animals, birds and pests Animals and domestic pets carry pathogens on their bodies and in their intestines. Staphylococcus aureus is commonly found on the noses and skin of cats and dogs this can be spread on the hands and clothes of food handlers. Salmonella are often present in the intestines of animals and pets, wild birds carry salmonella as do insects and pests, rats also spread Weils disease by urinating on surfaces and food items. Equipment Including work surfaces, knives, chopping boards, utensils, pots etc. if not cleaned and disinfected correctly can contaminate food with pathogenic bacteria. 2

3 VEHICLES AND ROUTES FOR BACTERIAL CONTAMINATION Sometimes bacteria pass directly from the source to high-risk foods but as bacteria are mainly static they rely on other things to transfer them to food. These things are known as vehicles and the main ones are: Hands. Cloths and equipment (knives, chopping boards, mixing bowls). Hand contact surfaces. Food contact surfaces. Cross contamination is defi ned as the transfer of bacteria from contaminated foods (usually raw) to other foods. This includes direct contact (raw foods touching high-risk foods) and indirect contact (hands, equipment or work surfaces). Handling of food should be minimised, wiping cloths used sparingly, disposable are preferred, hand contact surfaces, such as tap handles should be where possible, replaced with non-hand operated systems and the number of surfaces that food comes into contact with should be limited. Control of bacterial contamination Purchase food and raw materials from known, approved, reliable and hygienic suppliers. Check all deliveries and vehicles carefully, remove deliveries immediately to appropriate storage. Prevent cross-contamination. Crosscontamination occurs when bacteria are transferred onto food either directly (e.g. when raw and cooked food come into direct contact, sneezing or coughing onto food) or indirectly (e.g. via a vehicle such as from dirty utensils, pests, hands etc.) Prepared and cooked foods should be stored separate to raw foods and unprepared vegetables to reduce the risk of crosscontamination. Keep stored foods covered or otherwise protected at all times. Prevent animals, pets, pests and insects entering the food room, implement an integrated pest management system. Keep food preparation areas, equipment and utensils clean and disinfected. Ensure good personal hygiene practices are followed by staff and visitors at all times. Remove waste foods from kitchen as soon as is practicable, store in lidded bins away from food. Ensure cold water supplies used for food preparation are of potable quality. Store foods at safe temperatures - either cold below 5 C or hot above 63 C. Do not prepare food too far in advance, serve food immediately after cooking whenever possible. Cook food thoroughly, food must reach a minimum core temperature (temperature at the centre of the food) of 75 C this also applies to reheated food items. (Food must only be re-heated ONCE). If cooked food is not to be served immediately then it should be stored at above 63 or cooled rapidly, within 90 minutes and stored in the fridge. Remember that cooked food may contain bacterial spores. Viruses can be carried into the work place by food handlers who are carriers, viruses can also be present in foods such as shellfi sh or vegetables that have been in contact with sewage polluted water. Mould spores can be found in the air and on damp surfaces, food can become mouldy by storing at incorrect temperatures in high humidity. Some moulds are not harmful (although some strains produce mycotoxins which can cause vomiting and diarrhoea and may be carcinogenic) but the presence of mould is deemed to be unacceptable and prosecution may result as food contaminated with mould is unfit for human consumption. Yeasts are used in the production of bread, beer and vinegar and are not usually considered to cause food poisoning but several species cause food spoilage especially in acidic foods that have a high sugar content such as jam, fruit, fruit juice, honey and wine. 3

4 Preventing viral contamination and mould growth Purchase food and raw materials from known, approved, reliable and hygienic suppliers. Ensure that food handlers, all visitors etc. maintain high standards of personal hygiene. Ensure that correct hand washing procedures are being followed at all times. Ensure that staff understand and follow company procedures for reporting sickness and other illnesses. Keep areas clean and well ventilated. Keep food covered and dispose of any items that have become mouldy. Handle tinned and vacuum packed foods carefully to prevent damage or piercing to the packaging which would allow mould spores to settle. PHYSICAL CONTAMINATION Physical contamination is anything that falls onto or into food in the form of foreign bodies (undesirable contaminants that are usually solid matter). Foreign bodies found in food may be brought into the premises with the raw materials or introduced during storage, preparation, cooking, service or display. Sources of physical contamination include: People People including food handlers, contractors, delivery personnel and visitors are a common source of physical contaminants such as: hair, jewellery, fingernails, cigarettes and sweet wrappers. Raw ingredients Stones, grit, stalks, sticks, bones, shells, insects and pests can be present in food deliveries and may lead to contamination. Packing materials Plastic, string, wood, metal, staples, packing tape, polythene, cardboard etc. are all items from packaging materials that may contaminate food. Pests Droppings, fur, feathers, eggs, larvae and dead bodies are all possible causes of contamination. Structure, maintenance and repair Flakes of paint, plaster from ceilings and walls, rust from pipes or machinery, nuts, bolts, screws can all become physical contaminants in food. Wood Wooden splinters from containers and pallets can contaminate food. Glass Broken dishes, windows and light bulbs all pose a contamination risk from glass fragments. Notices Drawing pins, sellotape and paper clips are all possible contaminants from notice boards. 4

5 Preventing physical contamination Eating, chewing gum and smoking must not be allowed in food areas. Personal hygiene standards must be observed by everyone entering food areas at all times. Company policy should ensure that food handlers do not wear jewellery. Suitable protective clothing, including head covering, must be worn correctly by all people entering food areas. Purchase food and raw materials from known, approved, reliable and hygienic suppliers. All raw materials must be visually checked prior to use, also powders should be sieved and liquids can be filtered. Food should be unpacked in a separate deboxing area and unwanted packaging disposed of immediately. Pest contaminants can enter the premises in raw foods, check deliveries carefully and reject if necessary. Staff should be trained to report any sightings of infestation, a reputable pest control company must be employed. Ceiling structure, pipes or equipment should be non-flaking and rust-free. Wooden containers for raw materials should be avoided as should wooden surfaces and wooden handled utensils. Unless used for containing the final product, glass should be avoided in food rooms. Perspex or wire glass windows should be used, diffusers should be fitted to fluorescent tubes. Notices used for warnings or instruction must be properly fixed and permanent, do not use drawing pins. ALLERGENS The allergen is most often a protein and several systems within the body may be affected, for example the respiratory system, the gastrointestional tract, the skin and the central nervous system. Reactions can be mild or extremely severe and may occur as soon as the food is consumed or up to 48 hours later. Common allergens include: Peanuts Nuts Eggs Milk Fish Wheat Crustacea Control of allergens Ensure that systems are in place to prevent possible allergens contaminating food that is meant to be allergy free. Ensure that staff are able to inform customers of all the ingredients in a dish, including sauces, garnishes and dressings and how the dish is cooked. Always include information about allergens on menus - for example, carrot cake contains nuts, pasta contains eggs, etc. Staff should be trained to understand the dangers of certain foods to people that are allergic to them and the importance of keeping areas and equipment clean to avoid cross contamination. Staff should be trained in how to recognise the symptoms of a possible allergic reaction and what action to take, for example dialing 999 and requesting an ambulance. Allergenic ingredients must be identifi ed in prepacked foods under the Food Labelling Regulations Notice boards should be kept out of food areas and be covered in perspex or similar sheeting. v Metal detection systems are often used on the final stage of a production line. 5