HYGIENE STORAGE OF RAW AND COOKED FOOD

HYGIENE STORAGE OF RAW AND COOKED FOOD

Introduction

Food shall be in sound condition, free from spoilage, filth, and other contamination and shall be safe for human consumption.  Food shall be obtained from sources that comply with all laws relating to food and food labeling. Use of home prepared or hermetically sealed food which has been processed in a place other than a wholesale food processing establishment is prohibited except where it is in compliance with Subpart , Reduced Oxygen Packaging, of this Part. Inadequate food temperature controls are common factors contributing to foodborne illness. Unless food is properly handled when purchased, stored, prepared, and served, contamination may occur. Proper food handling practices help prevent foodborne illness. Written guidelines should reflect the type of foodservice operations in place. There are different requirements to prepare and serve hot meals at dining centres and to the homebound than for meals prepared and delivered from a central kitchen. Likewise, the preparation and/or service of frozen meals require specific procedures. Regardless of the type of congregate or home delivered meal prepared and/or served, a critical element in maintaining food safety is to cook foods to appropriate temperatures and to keep perishable food products out of the temperature danger zone (between 41°F and 140°F).

Food and other products such as utensils and dinnerware must be packaged and delivered in a manner that prevents contamination and maintains proper food temperatures. State of the art food carrier and transport systems can safely deliver cold and hot food items and/or meals at proper temperatures within acceptable time frames. Protecting food from contamination is dependent upon the development of suitable standards and procedures and ensuring that these guidelines are followed.

Importance

All foods naturally contain small amounts of bacteria. But poor handling of food, improper cooking or inadequate storage can result in bacteria multiplying in large enough numbers to cause illness. Parasites, viruses, toxins and chemicals also can contaminate food and cause illness. Signs and symptoms of food poisoning vary with the source of contamination, and whether you're dehydrated or have low blood pressure. Generally they include:

•           Diarrhea

•           Nausea

•           Abdominal pain

•           Vomiting (sometimes)

•           Dehydration (sometimes)

•           Lightheaded or faint, especially on standing

•           A rapid heartbeat

TYPES OF MICRO-ORGANISMS OR SCANT IN THE FOOD

Food-borne organisms are bacteria, viruses, and parasites that can cause illnesses which are either infectious or toxic in nature. They enter the body through the ingestion of contaminated food or water. Every person is at risk of food-borne illness, although infants, the elderly, the immune compromised, and the malnourished are particularly at risk. Food-borne illness may be mild, seriously debilitating, or even fatal. Illness is typically characterized by diarrhea, vomiting, or both, but it can also involve other parts of the body, such as the central nervous system. Food-borne illness outbreaks most often result from inadequate cooking, inadequate holding temperatures, cross-contamination, unsafe food sources, and poor personal hygiene.

Microorganisms or microbes are microscopic organisms that exist as unicellular, multicellular, or cell clusters. Microorganisms are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six major types:

1.      Bacteria,

2.      Archaea,

3.      Fungi,

4.      Protozoa,

5.      Algae, and

6.      Viruses.

Let discuss about them:

1.      Bacteria:

All bacteria are unicellular prokaryotes, meaning they do not have a defined cellular nucleus. Their genetic information is in their nucleoid, - single, circular tightly- packed DNA molecule. According to their shape, all bacteria are divided into three groups:

·         Spirilla (with a spiral body shape);

·         Cocci (with a spherical body shape);

·         Bacillus ( with a rod (stick) shaped body).

Some types of bacteria live on their own and others form colonies. Some bacteria are quite mobile and others 'stay put' for their whole life. Bacteria move using their cytoplasmic tail - flagella, or by secreting slimy substances that allow them to slide along surfaces.

Based on their response to gaseous oxygen, all bacteria can be divided into the following groups:

Aerobic - living in the presence of oxygen;

Anaerobic - living without oxygen;

Facultative anaerobes - can live in both environments.

2.      Archaea (bacteria)

Archaea were once thought to be a type of bacteria. After extensive research of their DNA and membrane structure, some scientists decided to put them into a separate group - Archaea. Another group of scientists is still not convinced and refers to them as Archaeabacteria. Archaeans can survive these extreme conditions due to their physiology. They synthesise different enzymes that keep their cells from being destroyed by high temperatures, salty or acidic water. Because of their 'fondness' for extreme environmental conditions, Archaeans are believed to be the first living forms that appeared on Earth when it was still waterless, airless and a scorching hot planet. Based on their habitat, all Archaeans can be divided into the following groups:

·         Methanogens - methane-producing organisms;

·         Halophiles - Archaeans that live in salty environments;

·         Thermophiles - Archaeans that live at extremely hot temperatures;

·         Psychrophiles - cold-temperature Archaeans.

Archaeans use different energy sources like hydrogen gas, carbon dioxide and sulphur. Some of them use sunlight to make energy, but not the same way as plants do. These creatures absorb sunlight using their membrane pigment, bacteriorhodopsin.

3.      Algae

It is also called Cyanobacteria or blue-green algae. Cyanobacteria are aquatic, photosynthetic organisms. They can be unicellular or colonial. Cyanobacteria are sometimes called blue-green algae. Like other plants, they make their energy through photosynthesis, but besides that, they do not have anything in common with plants. Millions of years ago, the atmospheric oxygen that we depend on was generated by cyanobacteria. Most cyanobacteria live in water, damp soil and rocks.

4.      Protozoa

Protozoa is a subkingdom of unicellular, mostly aerobic, eukaryotic organisms. Sometimes they are also called protists. They are neither plants nor animals. They make up the largest group of organisms in the world in terms of numbers and biomass. Some protozoans, like Euglena, have chloroplasts like plants and make their own food, which makes them autotrophs. Others, like amoeba, are heterotrophs. Protozoans can be free-living or parasitic, unicellular or colonial. Some parasitic protozoans can cause diseases in humans. Protozoans move around using their flagella or pseudopodia - cytoplasmic temporary 'feet'.

5.    Fungi

Fungi are saprophytic (feed on decaying organic matter) and parasitic organisms. Fungi include moulds, rusts, mildews, smuts, mushrooms and yeast. By breaking down dead organic material, they continue the cycle of nutrients through ecosystems. Some plants have a symbiotic relationship with fungi. Symbiosis is a mutually beneficial co-existence of dissimilar organisms. For example, there are mushrooms that live near tree roots and supply them with essential nutrients. All fungi are made of eukaryotic cells. Fungican be single-celled or with cells arranged in filaments called hyphae. Yeasts are unicellular fungi. Masses of hyphae are called mycelia. Mycelia can be well structured, as in a mushroom, or tangled and unstructured, as in moulds. Some fungi can exist in the form of yeast and hyphae. These types of fungi are called dimorphic.

All fungi are heterotrophic, meaning that they obtain their energy and carbon compounds from organic nutrients. None of the fungi are photosynthetic. Some fungi are parasites and can cause diseases in humans, animals and plants. Some fungi are used in the food industry and pharmaceutics (antibiotic production)

6.      Viruses

Although viruses are not considered living organisms, they are sometimes classified as microorganisms. Viruses are much smaller than common microbes. They are made of a DNA molecule covered with a protein shell called a capsid. Retroviruses are made of an RNA molecule covered with a capsid. Capsids can take many shapes. Viruses cannot reproduce outside the host cell, but they cannot be called parasites either. Scientists still argue today about whether viruses are true living forms because they are not cells and they cannot metabolise on their own. Viruses can infest prokaryotic and eukaryotic cells, often causing diseases in organisms. A virus that infects bacteria is known as a bacteriophage.

KNOWLEDGE OF SAFE vs. DANGER ZONES FOR STORING FOOD

Incorrect storage of food can cause spoilage and food poisoning. High-risk food should be kept at 5 °C or below, and above 60 °C (41°F and 140°F) to avoid the 'temperature danger zone', where bacteria multiply fastest. Do not refreeze food that has been frozen and thawed once.

Safe and unsafe temperatures

Use of correct storage temperatures for food is extremely important. Between 5°C and 60°C is called the 'temperature danger zone'. This is the temperature range in which potentially harmful bacteria can multiply. Perishable food should be stored at or below 5°C, or at or above 60°C to prevent growth of harmful bacteria. Correct cooking temperatures are very important especially for some meats, sausages and poultry. The temperature of all parts of minced, rolled or stuffed meats should reach at least 75 °C during cooking. This can be measured with a thermometer or can be recognised as very hot in the mouth. If food is to be held hot for some time after cooking and before serving, it should be held at or above 60°C. Or if the food is to be retained for serving at a subsequent meal or other occasion it should be refrigerated promptly. Make sure poultry, such as a whole chicken, reaches at least 75°C during cooking. Alternatively, cook until the juices run clear when pierced at the thickest point (such as the middle of drumstick). While reheating refrigerated food, the centre of the food should reach at least 75°C.

Danger zone (food safety)

The temperature range in which food-borne bacteria can grow is known as the danger zone. Food safety agencies, such as the United States' Food Safety and Inspection Service, define the danger zone as roughly 4–5 to 60 °C (39–41 to 140 °F). Potentially hazardous food should not be stored at temperatures in this range in order to prevent foodborne illness, and food that remains in this zone for more than two hours should not be consumed. Foodborne microorganisms grow much faster in the middle of the zone, at temperatures between 21 and 47 °C (70 and 117 °F).

Time and temperature control plays a critical role in food safety. To prevent time-temperature abuse, minimize the amount of time food spends in the danger zone. A logarithmic relationship exists between microbial cell death and temperature: a significantly large number of cells may survive slightly lower temperatures. In addition to reducing the time spent in the danger zone, foods should be moved through the danger zone as few times as possible when reheating or cooling. In order to ensure that foods are kept out of the danger zone, the use of food grade thermometers is recommended. Refrigerators should be kept below 4.4 °C (40 °F). To facilitate cooling, food can be layered thinly in a shallow dish to maximize the surface area exposed to the low temperature.

Food-poisoning bacteria can grow and multiply on some types of food more easily than others. High-risk foods include:

• Raw and cooked meat, including poultry such as chicken and turkey, and foods containing these, such as casseroles, curries and lasagne
• Dairy products, such as custard and dairy based desserts like custard tarts and cheesecake
• Eggs and egg products, such as quiche
• Small goods such as hams and salamis
• Seafood, such as seafood salad, patties, fish balls, stews containing seafood and fish stock
• Cooked rice and pasta
• Prepared salads like coleslaws, pasta salads and rice salads
• Prepared fruit salads
• Ready to eat foods, including sandwiches, rolls, and pizza that contain any of the food above.

Food that comes in packages, cans and jars can become high-risk foods once opened, and should be handled and stored correctly.

Storing food in the fridge

 Fridge temperature should be at 5 °C or below. The freezer temperature should be below -15 °C. Use a thermometer to check the temperature in your fridge.

Storing cooked food safely

 Cooked food and want to cool it:

 Put hot food into shallow dishes or smaller portions to help cool the food as quickly as possible.

 Don’t put very hot food into the refrigerator. Wait until steam has stopped rising from the food before putting it in the fridge.

Avoid refreezing thawed food: Food-poisoning bacteria can grow in frozen food while it is thawing, so avoid thawing frozen food in the temperature danger zone. Keep defrosted food in the fridge until it is ready to be cooked. If using a microwave oven to defrost food, cook it immediately after defrosting.

As a general rule, avoid refreezing thawed food. Food that is frozen a second time is likely to have higher levels of food-poisoning bacteria. The risk depends on the condition of the food when frozen, and how the food is handled between thawing and refreezing, but raw food should never be refrozen once thawed.

Store raw food separately from cooked food

Raw food and cooked food should be stored separately in the fridge. Bacteria from raw food can contaminate cold cooked food, and the bacteria can multiply to dangerous levels if the food is not cooked thoroughly again. Raw foods should always be stored in sealed or covered containers at the bottom of the fridge. Keep raw foods below cooked foods, to avoid liquid such as meat juices dripping down and contaminating the cooked food. Choose strong, non-toxic food storage containers

Make sure your food storage containers are clean and in good condition, and only use them for storing foods. Cover them with tight-fitting lids, foil or plastic film to minimise potential contamination. Transfer the contents of opened cans into suitable containers.

If in doubt, throw it out, Throw out high-risk food left in the temperature danger zone for more than four hours – don’t put it in the fridge and don’t keep it for later. Check the use-by dates on food products and discard out-of-date food. If you are uncertain of the use-by date, throw it out.

Things to remember

·         Keep high-risk food at 5 °C or below and above 60 °C to avoid the temperature danger zone.

·         Store raw foods below cooked foods.

·         Store food in suitable, covered containers.

·         Avoid refreezing thawed foods.

·         Check and observe the use-by dates on food products.

·         Take special care with high-risk foods.

Frozen foods

Freezing food at -18°C stops bacteria from growing and slows down chemical changes which may affect the quality of food.

Frozen food should be placed straight in the freezer when you return home from shopping.

Some foods, such as vegetables, chops and steaks, can be cooked directly from the frozen state. Food such as minced, rolled or stuffed meats and poultry should be completely thawed before cooking. This is best done in a refrigerator at or below 5°C.

If needed at short notice, packaged frozen food can be defrosted under cool running water or in a microwave. Thawed food which will be cooked (e.g. raw meat), may be refrozen but quality will be reduced.

Correct holding temperature

·         Keep hot foods hot and cold foods cold.

·         Hot foods keep at 140° F or above.

·         Cold foods refrigerate at 41° F or below.

·         Use a calibrated probe thermometer to check internal food temperatures.

Holding hot foods

·         Transfer hot foods directly to an oven, steam table, or other holding unit. Do not heat foods in a steam or holding unit.

·         Reheat leftover foods to 165° F prior to placing in a holding unit. If possible, avoid cooking foods more than one day ahead of time.

·         Stir foods at frequent intervals to evenly distribute heat. Keep a cover on foods to help maintain temperatures. Break the chain of possible food contamination.

·         Never combine an old batch of food with a new batch. Check the temperature of the foods on a frequent and regular basis. Use a clean and sanitized thermometer.

·         Don’t rely solely on the thermostat gauges of the holding equipment. They may not accurately indicate the internal temperature of the food.

Holding cold foods

·         Keep foods in cold-holding tables, commercial refrigerated display cases, and refrigerators.

·         Keep food in salad bars and display units, set the food containers in ice to keep them below 41° F.

·         Keep a cover on foods held in cold holding units to help maintain temperatures.

·         Check the temperature of the foods on a frequent and regular basis. Use a clean, sanitized thermometer.

·         Calibrating a thermometer using the ice method

·         Immerse the temperature probe at least two inches into a glass of finely crushed ice.

·         Add cold tap water to remove air pockets. Wait at least 30 seconds. The gauge should read 32°F; if not, adjust it accordingly.

Potato

·         Potatoes should store in a cool, dark place that is well ventilated.

·         Ideal storage temperature is 45 to 50°F.

·         Never refrigerates fresh potatoes. Potatoes stored below 40°F will be darker when cooked and have a sweeter flavor due to the conversion of starch into sugar.

·         AVOID prolonged exposure to light, which can turn the potatoes green.

·         USE boiled potato pieces within 2 hours; refrigerate unused portion.

Storage of cheese

·         Unpasteurised cheese with a range of flavours should not be sliced until purchase otherwise it will start to lose its subtlety and aroma.

·         Keep the cheese in conditions in which it matures. Hard, semi-hard   and semi -soft cheeses are temperatures from around 8° – 13° C.

·         Keep the cheese wrapped in the waxed paper and place it in a loose-fitting food-bag not to lose humidity and maintain the circulation of air.

·         Chilled cheeses should be taken out of the refrigerator one and a half or two hours before serving. Cheeses contain living organisms that must not be cut off from air, yet it is important not to let a cheese dry out.

·          Do not store cheese with other strong-smelling foods. As a cheese breathes, it will absorb other aromas and may spoil.

·         Wrap soft cheeses loosely. Use waxed or greaseproof paper rather than cling film.

·         Let cold cheese warm up for about half an hour before eating

Safe Storage of Chicken

·         Fresh, raw chicken can be stored in its original wrap for up to two days in the coldest part of the refrigerator. However, freeze chicken immediately if you do not plan to use it within two days after purchasing. You can freeze most chicken in its original packaging safely for up to two months; if you plan to freeze it longer, consider double-wrapping or rewrapping with freezer paper, aluminium foil, or plastic wrap.

·         Stocking the freezer with boneless, skinless chicken breasts and thighs can be a real timesaver. Divide the chicken into efficient, meal-size portions and package for freezing. These convenient packages defrost and cook quickly and eliminate leftovers.

·         Airtight packaging is the key to freezing chicken successfully. When freezing whole chickens, remove and rinse giblets (if any) and pat dry with paper towels. Trim away any excess fat from the chicken. Tightly wrap, label, date, and freeze both chicken and giblets in separate freezer-strength plastic, paper, or foil wraps.

·         Thaw frozen chicken, wrapped, in the refrigerator for best results. Thawing times for frozen chicken can vary depending on how thoroughly frozen the chicken is and whether the chicken is whole or cut up.

Freezer:

Keep freezer temperature at or below 0 °F. A good indication of proper temperature is that ice cream will be frozen solid. Use moisture-proof, freezer-weight wrap. Examples are foil, freezer bags and freezer paper. Label and date all packages. Food stored beyond the recommended time will be safe to eat, but eating quality (flavour and texture) and nutritive value may be reduced. Keep an inventory of freezer contents.

Refrigerator:

Use a thermometer to check temperature; it must be between 34 °F and 40 °F at all times. Avoid frequently opening the refrigerator door, especially in hot weather. Wrapping perishable food prevents the loss of flavour and the mixing of flavour and odours resulting in, for example, onion-flavoured milk. Raw meat and poultry should be wrapped securely so that they do not leak and contaminate other foods. Place the store packages in a plastic bag or place the package on a plate to contain any juices. Clean up leaks with warm soapy water and sanitize with a solution of 1 teaspoon chlorine bleach to 1 quart water. Cooked meats and leftovers should be tightly wrapped to prevent leakage and drying out.

Pantry:

Storage cabinets should be cool and dry. Storage areas near oven ranges, hot water pipes or heating ducts should not be used because heat and moisture can cause a food to lose its quality more rapidly. Insect infestation can occur in any home. Susceptible foods include cereals, flour, seeds, baking mixes, spices, candy, dried fruits and dry pet foods. Avoid purchasing damaged packages of foods and keep cupboard shelves clean. Storing food in tightly sealed glass, metal or rigid plastic containers may help. Pantry foods will probably be safe beyond recommended storage time, but eating quality (flavour and texture) and nutritive value may be reduced.

FIFO

For best results in maintaining product quality, practice the rule, First In, First Out (FIFO). This means the oldest products should be used first and the newest products later. A good practice is to place the newly purchased products in back of the same products already on the shelf. Follow recommended storage times for the refrigerator, freezer and pantry:

FOOD PRESERVATION METHODS

Food preservation usually involves preventing the growth of bacteria, fungi (such as yeasts), and other micro-organisms (although some methods work by introducing benign bacteria, or fungi to the food), as well as retarding the oxidation of fats that cause rancidity. Food preservation can also include processes that inhibit visual deterioration, such as the enzymatic browning reaction in apples after they are cut, which can occur during food preparation.

Many processes designed to preserve food will involve a number of food preservation methods. Preserving fruit by turning it into jam, for example, involves boiling (to reduce the fruit’s moisture content and to kill bacteria, yeasts, etc.), sugaring (to prevent their re-growth) and sealing within an airtight jar (to prevent recontamination). There are many traditional methods of preserving food that limit the energy inputs and reduce carbon footprint.

Maintaining or creating nutritional value, texture and flavour is an important aspect of food preservation, although, historically, some methods drastically altered the character of the food being preserved. In many cases these changes have come to be seen as desirable qualities – cheese, yoghurt and pickled onions being common examples.

Commercial, the food preservation technique depicts the following processes:

1.      Canning and Bottling

2.      Machine Drying

3.      Freeze drying

4.      Cold storage

5.      Pasteurization

6.      Irradiation

7.      Use of antibiotics.

1. Canning and bottling:

Canning involves the process of preserving foods in sealed containers by the application of heat. Primarily, it is based on the principle of sterilization. Firstly, all the micro-organisms present in the food are killed by the applications of heart at 275° to 350°F and then sealed in simultaneously sterilized air tight containers to prevent any further attack of microorganism. Fruits, vegetables, fruit juices, pickles, cheese, butter, meat, fish etc. are generally canned or bottled.

2. Machine drying:

Dehydration in sunlight is an ancient and the lengthiest process of preserving food practiced at every homes. Understanding the difficulties of this process of preserving food, Scientists have invented different machines to be used for different food stuffs, which are dried at different temperatures. Commercially special type of steam rollers are used for drying milk for reducing it to powder. Similarly, special ovens are sued for drying vegetables at a specific temperature. It is found that this method of preservation is better than those of the traditional method of drying foods in sunlight.

3. Freeze drying:

This method of preserving food is adopted to overcome the difficulties of machine or Sunlight drying. During drying vegetables or fruits by Sunlight or by machine, foods are too much squeezed, and do not take the original shape when it is in use. In order to overcome this defect, the process of freeze drying was invented. In this process, food stuffs are kept at a temperature of -20°C for about 12 hours, so that the water content of the food stuffs are converted to ice particles. Then it is dried up by machine under low pressure. When it is to be used, it is dipped in hot water. This method retains the shape of the food stuffs, which is damaged by machines drying process.

4. Cold Storage:

This system has become one of the most popular methods of preserving food-stuffs in rural and urban areas of today. Many seasonal fruits and vegetables are stored in cold storages and according to the demand of the market are carried to the place of requirement. This method is based on the principle of refrigeration. Mostly, vegetables, fruits, eggs, meat, fish are kept in cold storages.

5. Pasteurization:

This process is applicable to milk only. In this method milk is boiled at 160°F and then immediately cooled at 55°F. Normally, milk is pasteurised on a large scale to safeguard against any bacterial infection. The process aims at destroying the bacteria and inactivating the rest ones. The pasteurised milk is filled in sterilised bottles which are sealed. It could be preserved for five to six days and the colour and flavor of pasteurised milk does not change in the process, as happens with the boiled milk.

6. Irradiation:

This is a new technique of preservation, which is at the stage of experimentation. The W.H.O. has advised the use of this process only in the case of wheat, onions and potatoes. In this process, gamma rays or high speed electrons are used to destroy micro-organism. These radiations are termed as ionising radiations. The best advantage of this process is that the food can be stored without refrigeration.

7. Use of antibiotics:

This is another method of preservation now under study. Use of antibiotics in food stuffs have considerably, increased during these days. When fish and poultry are treated with antibiotics, their self-life increases two to three times because of the reduced growth of the micro-organisms. Similarly antibiotics are used in the ice crush, which is used for packing raw fish and shell fish.

The choice of food preservation will depend on weighing up the advantages and disadvantages of each method. You should consider the following factors when deciding on which method to use:

·         Space: The amount of space you have will definitely impact on your choice of preservation. Someone living in a farmhouse can probably store dozens of preserved fruits in jars, whereas someone living in an apartment is unlikely to have the space to spare for rows of preserved plums.

·         Climate: The climate can aid or hinder different storage methods. What might store beautifully through a Canadian winter may well rot during an Australian one.

·         Available equipment: Some preserving methods require specialised equipment that you may not have access to, or that you may be unwilling to use. For example, not everybody enjoys the sterilization process required to preserve fruit in jars and not everyone can build a smokehouse.

·         Cost: Naturally, the costs involved in preserving your food should be weighed against the cost of purchasing the food from a local market, supermarket or other source. In addition, there may be costs in using up storage space, costs in purchasing equipment etc. Care should be given, however, to include the benefits of enjoyment from preserving one's own food, as well as the health, environmental and nutrient benefits that might arise from preserving home grown produce, costs that are very hard to quantify and should weigh heavily in your decision-making.

·         Nature of the food: Be realistic about the ability of the food to be preserved. Some food will not tolerate any form of preserving and needs to be eaten fresh. This means that you need to do your research. Also, some foods change during the preserving process and become less palatable or even take on characteristics that are less health-giving. For example, use of nitrites to preserve meat can turn healthy meat into a potentially carcinogenic product.

·         Hygiene and safety: Ability to maintain a high level of hygiene and safety during the preservation process is important. If you cannot meet basic standards, it is best to not attempt a particular preservation method and to either substitute for a safer method or choose to not preserve the food.

·         Other issues: Perhaps there are health issues involved in preserving. For example, some people are unable to tolerate preservatives used to create dry fruit. Whilst it is possible to dry them organically, they will discolour and this may not be to the liking of some consumers.

FOOD BORNE DISEASES

Foodborne diseases are too frequently considered to mean only those diseases that most often show at least some gastrointestinal tract symptoms. While these diseases are the ones most often proven to be food transmitted to means the only infectious diseases that are transmitted to human by contaminated food, is known as Foodborne diseases.

A microorganism is a microscopic form of life found on all non-sterilized matter that can be decomposed. The word is of Greek origin and means “small” and “living beings.” These organisms metabolize in a manner similar to humans through nourishment intake, discharge of waste products, and reproduction. Most foods are highly perishable because they contain nutrients required for microbial growth. To reduce food spoilage and to eliminate foodborne illness, microbial proliferation must be controlled. Food deterioration should be minimized to prolong the time during which an acceptable level of flavour and wholesomeness can be maintained. In developed countries, surveillance of foodborne disease is a fundamental component of food safety systems. Surveillance data are used for planning, implementing and evaluating public health policies. There is therefore a strong need to strengthen surveillance systems for foodborne disease.

Three types of microorganisms occur in foods. They may be beneficial, pathogenic, or cause spoilage. Beneficial microorganisms include those that may produce new foods or food ingredients through fermentation(s) (e.g., yeasts and lactic acid bacteria) and probiotics. Spoilage microorganisms, through their growth and ultimately enzymatic action, alter the taste of foods through flavor, texture, or color degradation. Pathogenic microorganisms can cause human illness. Two types of pathogenic microorganisms that grow in or are carried by foods are those that cause: intoxication and infection. Intoxication results from microorganisms growing and producing toxin (which causes the illness) in a food. An infection is an illness that results from ingestion of a disease-causing microorganism. Infectious microorganisms may cause illness by the production of enterotoxins in the gastrointestinal tract or adhesion to and/or invasion of the tissues. Some most common foodborne diseases are:

Shigella is a genus of bacteria that are a major cause of diarrheoa and dysentery – diarrhoea with blood and mucus in the stools – throughout the world. The bacteria are transmitted by ingestion of contaminated food or water, or through person-to-person contact. In the body, they can invade and destroy the cells lining the large intestine, causing mucosal ulceration and bloody diarrhoea. Apart from diarrhoea, symptoms of Shigella infection include fever, abdominal cramps, and rectal pain. Most patients recover without complications within seven days. Shigellosis can be treated with antibiotics, although some strains have developed drug resistance.

Bovine spongiform encephalopathy (BSE) is a transmissible, neurodegenerative, fatal brain disease of cattle. The disease has an incubation period of 4-5 years, but death usually occurs within months of disease onset. The disease first came to prominence in 1986, when it appeared in cattle in the United Kingdom. BSE has been linked to the appearance in humans of variant Creutzfeldt-Jakob disease.

Salmonella is a genus of bacteria that are a major cause of foodborne illness throughout the world. The bacteria are generally transmitted to humans through consumption of contaminated food of animal origin, mainly meat, poultry, eggs and milk. The symptoms of Salmonella infection usually appear 12–72 hours after infection, and include fever, abdominal pain, diarrhoea, nausea and sometimes vomiting. The illness usually lasts 4–7 days, and most people recover without treatment. However, in the very young and the elderly, and in cases when the bacteria enter the bloodstream, ant biotherapy may be needed.

Campylobacter is a genus of bacteria that are a major cause of gastroenteritis throughout the world. Infection occurs mainly following consumption of contaminated undercooked poultry or contaminated water. The most common symptoms of campylobacter infection include diarrhoea, abdominal pain, fever, headache, nausea and vomiting. Symptoms usually start 2–5 days after infection, and last for 3–6 days. Specific treatment is not usually necessary, except to replace electrolytes and water lost through diarrhoea, but antimicrobials may be needed to treat invasive cases and the carrier state. Severe complications, such as Guillain-Barré syndrome, may follow campylobacter infection.

Escherichia coli is a bacterium that is commonly found in the gut of humans and other warm-blooded animals. While most strains are harmless, some can cause severe foodborne disease. E. coli infection is usually transmitted through consumption of contaminated water or food, such as undercooked meat products and raw milk. Symptoms of disease include abdominal cramps and diarrhoea, which may be bloody. Fever and vomiting may also occur. Most patients recover within 10 days, although in a few cases the disease may become life-threatening.

Botulism is, in humans, a rare but sometimes fatal paralytic illness. Foodborne botulism is an intoxication caused by consuming food contaminated with the botulinum toxin; it is not passed on from person to person when the skin is intact. Infant botulism is a toxico-infection where the gastro-intestinal tract is colonized by spores prior to the protective intestinal bacterial flora having developed and wound botulism is found most often among substance abusers when spores enter a wound under the skin, and, in the absence of oxygen are activated and release toxin.

Some more diseases are

·         Campylobacteriosis

·         Clostridium perfringens

·         Cryptosporidiosis

·         Hepatitis A

·         Norovirus

·         Shigellosis

·         Typhoid Fever

·         Vibriosis

·         Yersiniosis

·         Intoxication

·         Allergic reaction

·         Fish toxins

·         Seafood toxins

FOOD POISONING OF DIFFERENT TYPES

Aerobic spoilage by bacteria and yeasts usually results in slime formation, undesirable odours and flavours (taints). Colour changes, rancidity, tallowy or chalky flavours from the breakdown of lipids may also occur. Colour changes as a result of pigment oxidation may be grey, brown or green discoloration. Aerobic spoilage by moulds results in a sticky surface, musty odours, alcohol flavours and creamy, black or green discoloration. Anaerobic spoilage which occurs either within the meat or on the surface in sealed containers where oxygen is absent or very limited is marked by a souring due to the production of organic acids and gases.

Food poisoning is a common, yet distressing and sometimes life-threatening problem for millions of people throughout the world. People infected with foodborne organisms may be symptom-free or may have symptoms ranging from mild intestinal discomfort to severe dehydration and bloody diarrhea. Depending on the type of infection, people can even die as a result of food poisoning. More than 250 different diseases can cause food poisoning. Some of the most common diseases are infections caused by bacteria, such as Campylobacter, Salmonella, Shigella, E. coli O157:H7, Listeria, and botulism.

There are many different types of food poisoning. The most common are Campylobacter and Salmonella and unfortunately the numbers of people affected by Campylobacter is increasing year after year. Cases of Salmonella have declined due to immunisation of flocks

The young and the elderly are particularly at risk and those people whose job involves handling food, working with children or nursing may pass the infection onto others. Food poisoning may be due to infection or intoxication. Infection is caused by the consumption of live bacteria which multiply in the body producing characteristic symptoms. Intoxication is due to toxins in food produced by bacteria before the food was eaten. Toxins are chemical compounds which may linger in food with no microbes growing in it, and are therefore very dangerous.

Types of Food Poisoning

There are four main types of food poisoning:

·         Salmonellae

·         Staphylococcus aureus

·         Clostridium botulinum

·         Clostridium perfringens

           I.            Salmonellae are facultative anaerobes which cause infectious food poisoning. 10 or 20 cells of Salmonella typhi are sufficient to cause typhoid but 10 000 to 100 000 cells of other species may be necessary to cause an infection. Some are host-specific affecting the animal from which the meat was produced but failing to cause infection when consumed by man. Typical symptoms of salmonellosis include diarrhoea, fever and vomiting. The illness may last one to 14 days after a 12 to 24-hour incubation period. Victims may excrete the bacteria for weeks after the symptoms subside. Poor personal hygiene will cause contamination of meat.

        II.            Staphylococcus aureus is a facultative aerobe that causes intoxication. It lives in the nose, throat, hair and skin and on animal hides. Meat is contaminated by handling and by sneezing or coughing. Minute amounts of the toxin will cause illness, which starts within one to eight hours of eating poisoned food. Nausea, vomiting and shock may last for one to two days. On rare occasions it is fatal. This bacterium does not produce off-odours or spoilage so it cannot be easily checked. Refrigeration will control its growth. Cooking may destroy the bacteria but not the toxin as it is heat stable. It is particularly troublesome in cooked cured meats, normally as a result of recontamination after the curing process in subsequent handling, for instance during slicing.

     III.            Clostridium botulinum, an anaerobe, produces the toxin botulin, one of the most poisonous substances known. This attacks the central nervous system causing death by respiratory paralysis. Dormant cells occur everywhere in the soil, fish, animals and plants. High-moisture, low-acid, low-salt conditions at above 3°C favour growth and toxin production. Control measures must destroy spores or prevent growth and toxin formation. Botulism is usually due to undercooking processed meats. Pressure-cooking will give commercial sterility. Pasteurization (heating to 70°C) and adding salt (NaCl) and sodium nitrite (NaNO2) is used for canned ham. Refrigeration (0–10°C) is essential for vaccum-packed meats. Frozen storage prevents growth.

     IV.            Clostridium perfringens, an anaerobic bacterium, is a common cause of food poisoning but is rarely fatal. It grows well in warm meats so is usually found in left-over meats that have not been kept chilled and not been reheated to 70°C to kill the bacteria present. The main symptoms are diarrhoea and weakness which last for 12 to 24 hours after an incubation period of eight to 20 hours.

Below is some basic information about the most common types of food poisoning:

Campylobacter

Sources - undercooked poultry and meat, untreated milk or 'milk pecked' by birds, untreated water, contact with domestic animals and shellfish.

Symptoms - severe diarrhoea sometimes containing blood and abdominal pain

Spread - Via food (undercooked or via cross contamination, water or from animals.

Incubation period (the time it takes from eating the suspected food until symptoms begin) - 1-10 days, usually 2-5 days

Duration of illness - 2 days - 1 week

Control- Through cooking of poultry and meat, prevention of cross-contamination, pasteurisation of milk, water treatment and precautions when cleaning up after pets.

Salmonella

There are many different types of Salmonella, including typhi and paratyphi both known as enteric fever.

Sources - food such as raw eggs, undercooked poultry and meat, unpasteurised milk, infected food handlers and other people and animals.

Symptoms - diarrhoea, high fever, severe abdominal pain, vomiting.

Spread - Foodborne, due to inadequate cooking and/or cross-contamination made worse by poor handling/storage techniques, Sometimes directly from infected animals, Human to human contact from cases with diarrhoea.

Incubation period (the time it takes from eating the suspected food until symptoms begin) - usually 12-48 hours, occasionally up to 4 days.

Duration of illness- Up to 3 weeks may be a carrier for up to 12 weeks or longer after symptoms have subsided.

Control- Through cooking of poultry, meat and eggs, Good personal hygiene, Reduction of risk of cross-contamination, good temperature control etc.

Bacillus cereus

Sources:

·         Food - cereal products, rice, spices, dried foods, milk and dairy products.

·         Environmental - soil, dust, sediments

Symptoms:

·         Nausea, vomiting and stomach cramps. Diarrhoea may occur later

·         Acute diarrhoea and abdominal pain

Spread

·         Food: Contaminated cooked food, particularly rice and pasta dishes, dried foods and dairy products

·         Environment: soil, dust and sediments

Incubation period (the time it takes from eating the suspected food until symptoms begin)

1- 5 hours or 8-16 hours

Duration of illness: Usually no longer than 24-36 hours

Control: Correct cooking to minimise spore germination and multiplication. Cooked food should be held hot at 630C before consumption. Left over rice should be cooled quickly and placed in the fridge.

Ecoli– there are 2 types, one being carried by humans and Ecoli O157 caused by undercooked meat or unpasteurised/contaminated milk.

Sources: Humans

Symptoms: Diarrhoea with blood

Spread: Water, human contact via the faecal-oral route.

Incubation period (the time it takes from eating the suspected food until symptoms begin)

10 –18 hours

Duration of illness: 2 weeks

Control: Good standards of personal hygiene, through cooking of food

Ecoli O157

Sources: Under cooked beef, contaminated/unpasteurised milk

Symptoms: Range from mild diarrhoea to more serious bloody diarrhoea and can cause kidney damage.

Spread: By food, water and humans via the faecal-oral route

Incubation period (the time it takes from eating the suspected food until symptoms begin)

12 – 60 hours

Duration of illness: Variable

Control: Through cooking of meat until piping hot or juices run clear. Avoid cross-contamination of food

Clostridium Botulinum

Sources: Environment, soil, marine sediments, intestinal tracts of fish and animals

Symptoms: Diarrhoea and vomiting followed by constipation, double vision, dry mouth, difficulty in swallowing, weakness of limbs, paralysis and respiratory failure

Spread: Raw, undercooked or under-processed foods.

Incubation period (the time it takes from eating the suspected food until symptoms begin)

2 hours - 5 days. Usually 12 – 36 hours

Duration of illness: Up to 6-8 months

Control: Food processing technology

Clostridium Perfringens

Sources: Faeces of animals and man, soil, sewage, dust, feed of animal origin

Symptoms: Diarrhoea and abdominal pain

Spread: Contaminated bulk cooked meat and poultry dishes which have been left at ambient temperature during cooling and storage.

Incubation period: (the time it takes from eating the suspected food until symptoms begin)

8 – 18 hours

Duration of illness: 24 hours

Control: Adequate cooling, storage and re-heating of food

CAUSES OF FOOD SPOILAGE

Food spoilage means the original nutritional value, texture, flavour of the food are damaged, the food become harmful to people and unsuitable to eat. Food spoilage can be defined as “any sensory change (tactile, visual, olfactory or flavour) which the consumer considers to be unacceptable.

Foods by their nature are rich in carbohydrates, proteins and lipids that microbes as well as humans find very nutritious. Living plants and animals have structural and chemical defences to prevent microbial colonization, but once they are dead or in a dormant state these systems deteriorate and become less effective. Many different microbes may potentially be able to use the nutrients in a food but some species have a competitive advantage under certain conditions. Food processors should note that certain spoilage organisms may not grow on particular foods because some nutrient is missing. If the food product is reformulated, then a new ingredient may allow growth of previously unimportant microbe Different food categories present different challenges for inhibition of spoilage organisms.

Spoilage may occur at any stage along the food chain. Spoilage may arise from:

·         insect damage

·         Physical damage (bruising, freezing, drying, etc.)

·          indigenous enzyme activity in the animal or plant tissue

·         chemical changes (usually involving oxygen)

·         Spoilage is therefore complex, involving physical, chemical, biochemical and biological changes.

 

 

 

Causes of the spoilage of food

1.      Microbial spoilage

2.      Autolysis

3.      Others

1.      Microbial spoilage

There are three types of microorganisms that cause food spoilage -- yeasts, moulds and bacteria.

·         Yeasts growth causes fermentation which is the result of yeast metabolism. There are two types of yeasts true yeast and false yeast. True yeast metabolizes sugar producing alcohol and carbon dioxide gas. This is known as fermentation. False yeast grows as a dry film on a food surface, such as on pickle brine. False yeast occurs in foods that have a high sugar or high acid environment.

·         Moulds grow in filaments forming a tough mass which is visible as `mould growth'. Moulds form spores which, when dry, float through the air to find suitable conditions where they can start the growth cycle again. Mold can cause illness, especially if the person is allergic to molds. Usually though, the main symptoms from eating mouldy food will be nausea or vomiting from the bad taste and smell of the mouldy food.

·         Bacteria are round, rod or spiral shaped microorganisms. Bacteria may grow under a wide variety of conditions. There are many types of bacteria that cause spoilage. They can be divided into: spore-forming and non-spore forming. Bacteria generally prefer low acid foods like vegetables and meat. In order to destroy bacteria spores in a relatively short period of time, low acid foods must be processed for the appropriate length of time at 116°C (240°F) in a pressure canner. (Temperatures higher than 100°C [212°F] can be obtained only by pressure canning.) Eating spoiled food caused by bacteria can cause food poisoning.

Both yeasts and moulds can thrive in high acid foods like fruit, tomatoes, jams, jellies and pickles. Both are easily destroyed by heat. Processing high acid foods at a temperature of 100°C (212°F) in a boiling water canner for the appropriate length of time destroys yeasts and moulds.

Fungal Spoilage: Storage rot in grapes caused by Botrytis cinerea, Storage rot in strawberry caused by Botrytis cinerea, Blue mould rot in tomato caused by Penicilliumi spp. (also by Fusarium spp.) Black mummy rot of grapes caused by Guignardia bidwellii Watery soft rot in apple caused by Sclerotinia sclerotiorum, Blue mould on oranges caused by Penicillium digitatum.

2.      Autolysis

·         Enzymes: Enzymes are proteins found in all plants and animals. If uncooked foods are not used while fresh, enzymes cause undesirable changes in colour, texture and flavour. Enzymes are destroyed easily by heat processing.

·         Oxidation by air: Atmospheric oxygen can react with some food components which may cause rancidity or color changes.

3.      Other factors

·         Infestations (invasions) by insects and rodents, which account for huge losses in food stocks.

·         Low temperature injury - the internal structures of the food are damaged by very low temperature.

·         Low Temperature Injury: Internal mahogany browning of potato caused by low temperature injury.

·         Chilling injury in cucumber caused by low temperature. Note the watery surface.

There are three types of food decay:

•           Putrefaction

•           Fermentation

•           Rancidity

Putrefaction: Biological decomposition of organic matter, with the production of ill-smelling and tasting products, associated with anaerobic (no oxygen present) conditions.

Fermentation: Chemical changes in organic substances produced by the action of enzymes. This general definition includes virtually all chemical reactions of physiological importance, and scientists today often restrict the term to the action of specific enzymes, called ferments, produced by minute organisms such as molds, bacteria, and yeasts. For example, lactase, a ferment produced by bacteria usually found in milk, causes the milk to sour by changing lactose (milk sugar) into lactic acid.

Rancidity

(1) Microbial rancidity: Like all food components, fats undergo deteriorative changes with time, which result in undesirable flavors and odors. These changes in fats are given the term "rancidity".

(2) Hydrolytic rancidity: Fatty acids formed through hydrolysis of the lipid(fat) by the water which it contains. Some of the liberated fatty acids are volatile, and some have very unpleasant odours and flavours.

(3) Oxidative rancidity: The oxidation of acylglycerols which occurs in air, without the presence of enzymes, is called autoxidation. These have no taste, but they decompose easily to form aldehydes, ketones and acids, which give oxidised fats and oils their rancid flavours. It can be slow down by addition of antioxidants.

Food may be classified broadly into three groups based on their ease of spoilage:

Based on the perishability and the extent of preservation required, foods may be classified as:

        i.            Perishable foods: Those that deteriorate readily (fruits and vegetables) unless special methods of preservation are employed.

      ii.            Semi-perishable foods: Those that contain natural inhibitors of spoilage (root vegetables) or those that have received some type of mild treatment which creates greater tolerance to the environmental conditions and abuses during distribution and handling (such as pickled vegetables).

    iii.            Non-perishable foods (shelf-stable): Those that are non-perishable at room temperature (cereal grains, sugar, nuts). Some have been made shelf stable by suitable means (canning) or processed to reduce their moisture content (raisins). Food preservation in the broad sense, refers to all the measures taken against any kind of spoilage in food.

FOOD SAFETY MANAGEMENT PROGRAMME

It is important to set up a proactive Food Safety Management System to help protect your customers and your business from foodborne illnesses. Active Managerial Control (AMC) provides an excellent framework designed specifically to help you create a Food Safety Management System. It's free, easy to use and customizable. The Health Department works to protect the health of consumers by assuring that the food prepared and served in Macomb County's licensed food service establishments is wholesome and safe. This is accomplished through a variety of activities:

v  Make licensing recommendations to the Michigan Department of Agriculture

v  Conduct regulatory inspections at all licensed food service establishments

v  Provide training to food service operators

v  Require a certified food service manager at each licensed establishment

v  Investigate reported foodborne illnesses

Do you know Bacteria require a higher humidity than do yeasts and molds. Optimal relative humidity for bacteria is 92% or higher, whereas yeasts prefer it to be 90% or higher. Molds thrive more if the relative humidity is 85% to 90%. Bacterial growth follows a regular pattern that consist of four phases first is LAG PHASE, second is LOG PHASE, third is STATIONARY PHASE and DECLINE is last phase. In last phase the bacteria die off rapidly because they lack nutrients and are poisoned by their own toxic waste.

Summary

Storage does not improve the quality of any food. The quality of a food will also not decrease significantly during storage as long as the food is stored properly and used within the recommended time frame. Storage includes food in the refrigerator or freezer, vegetables in a garden or fruit on a tree, livestock, or food stored in a storage room. Management of this food is a vital part of food storage. Food is perishable even when stored properly under the most favorable circumstances and conditions. Proper storing and rotating food will preserve nutritional quality, eating quality, and eliminate waste.

Quality and nutritive value of food deteriorates during storage. Therefore foods should not be held for long periods beyond their established shelf-life. Rechauffe is the utilization of the “left-overs” by the reheating and redressing of already cooked foods. Although freshly cooked food is better than any which has been reheated, from an economical standpoint it is therefore an important branch of cookery.

Meat is generally considered to be the flesh of any animal and includes beef, veal, lamb, and pork along with poultry, fish, and shellfish. Meats in general are high in cholesterol than fish. In the descending order of cholesterol content, pork or products of pork in all forms are highest followed by beef, sheep / lamb and chicken. Organisms that cause food spoilage–molds, yeasts and bacteria–are present everywhere in the air, soil and water. Enzymes that may cause undesirable changes in flavor, color and texture are present in raw vegetables.

Food processing dates back to the prehistoric age when crude processing including various types of cooking, such as over fire, smoking, steaming, fermenting, sun drying and preserving with salt were in practice. Foods preserved this way were a common part of warriors’ and sailors’ diets. These crude processing techniques remained essentially the same until the advent of the Industrial Revolution. Nicolas Appert developed a vacuum bottling process to supply food to troops in the French army, which eventually led to canning in tins by Peter Durand in 1810. Modern food processing technologies, in the 19th century were also largely developed to serve military needs. In the early 20th century, the space race, change in food habits and the quality consciousness of the consumers in the developed world furthered the development of food processing with advancements such as spray drying, juice concentrates, freeze drying and the introduction of artificial sweetners, colourants, and preservatives. In the late 20th century products including dried instant soups, reconstituted fruit juices, and self cooking meals such as ready-to-eat food rations etc., were developed.

Definitions for Terms

Browning: Enzymes cause browning in certain foods the moment they are exposed to air. When you cut or bruise food such as apple or yam, the exposed surface will discolour and turn brownish due to the activity of enzymes.

CDC: centre for disease control and prevention.

CFP: conference for food protection.

Cross contamination: is what happens when bacteria from one food item are transferred to another food item, often by way of unwashed cutting boards or countertops, as well as knives and other kitchen tools, or even unwashed hands. Cross contamination can in turn lead to food poisoning.

EPA: Environmental protection agency.

FIFO: First In First Out.

FATTOM: Food Acid Temperature Time Oxygen Moisture, the conditions needed for growth of bacteria.

ICT: Internal core Temperature.

Incubation period: the time elapsed between exposure to a pathogenic organism, a chemical or radiation, and when symptoms and signs are first apparent.

Pickling: Pickle is an edible product preserved and flavoured in a solution of common salt and/or vinegar. The preservation of fruits and vegetables in common salt and/or in vinegar is called pickling. Spices and edible oils may be added to the product. Raw mango, lime, turnip, cabbage, cauliflower etc. are preserved in the form of pickles, which have become popular in several countries. Apart from having nutritional and therapeutic value, they have appetizing appeal.

Pasteurization: Pasteurization is a process of heat treatment used to inactivate enzymes and to kill relatively heat sensitive pathogenic microorganisms that cause spoilage, with minimal changes in food properties (e.g. sensory and nutritional).

ROP: reduced oxygen packaging. It is a process of prevention of food by reducing oxygen in a sealed package, either removing or replacing with other gas.

Sterilization: In this process foods are heated at a sufficiently high temperature (121°C) and for a sufficiently long time (10-15 minutes) to destroy microbial and enzyme activity. As a result, sterilized foods have a shelf life of more than six months. Higher temperature for a short time (140°C/3-4 seconds) is possible if the product is sterilized before it is filled into pre-sterilized containers in a sterile atmosphere. This forms the basis of Ultra High Temperature (UHT) processing (also termed aseptic processing). It is used to sterilize a wide range of liquid foods (fruit juices and concentrates, wine, etc.) and foods which contain small discrete particles (tomato products, fruit and vegetable soups).

Trichinosis: Disease that can arise from eating under-cooked pork or pork sausage meat; due to Trichinella spiralis, a worm that is a parasite in pork muscle.

CAP: Control atmosphere packaging. It is a process of extending self-life of food by the use of agents that bind or scavenge oxygen or a small packet containing packet to emit a gas.

MAP: modified atmosphere packaging.

Sous vide: fresh raw foods are sealed in a plastic pouch and the air is removed by vacuum.

TCS: temperature Control for Safety

Vacuum packaging: reduce air from package and hermetically seals the so that a near-perfect vacuum remains inside.

FIFO: first in first out.

GRAS: generally recognised as safe substances.

OSHA: occupational safety and health administration.

Microbes: A minute organism usually producing disease: bug, germ, and microorganism.

Pasteurize: To kill bacteria and other microbes by heating milk or other liquids to moderately high temperatures for a short period of time.

Rancidity: The development of unpleasant flavours in oils and fats as a result of oxidation. It is usually due to production of Free Fatty Acid (FFA) during storage of oil.

Food microbiology: Food microbiology is the study of the microorganisms that inhabit, create, or contaminate food. Including the study of microorganisms causing food spoilage.

Salmonellosis: Infection with Salmonella species. Found in meat, poultry, egg or milk products.

Yersiniosis: Infection with Yersinia enterocolitica in raw milk, chocolate milk, water, pork, other raw meats.

Rechauffe cooking: reheating of food

References: Principles of Food Sanitation (Fifth Edition) Norman G. Marriott and Robert B. Gravani, www.fsis.usda.gov, Food Safety in the Hospitality Industry, Butterworth-Heinemann. http://www.who.int.

TEST YOURSELF

1.    What is the correct temperature that frozen food should be kept at?

A.    0 ° 

B.     15 ° or lower

C.     -18 ° or lower

D.    20 ° or lower

2.    Which one of the following foods is likely to contain the MOST bacteria?

A.       Frozen raw chicken.

B.       Recently cooked chicken.

C.     An opened fizzy drink.

D.    Bottled mayonnaise.                                        

3.    Which of the following is true about bacteria;

A.    Bacteria multiply and grow faster in warm environments.

B.     Bacteria need air to survive.

C.     Every type of bacteria can give people food poisoning.

D.    By freezing food you can kill bacteria.

4.    The ideal temperature in your fridge should be?

A.    4 – 10 degrees

B.     1 and 4 degrees

C.     0 to 4 degrees

D.    -2 to 0 degrees                                                

5.    Which of the following powers does Environmental Health Officers NOT have?

A.    Authority to close down premises.

B.     The power of arrest.

C.     Authority to enter premises without appointment.

D.    The power to seize foods.

6.    It is important to prepare food safely because;

A.    It helps to prevent food poisoning.

B.     Prepared food looks better.

C.     Prepared food tastes better.

7.    If a food is cooked on the outside it will also be cooked on the inside.

A.       True

B.       False

C.     Can’t say

D.    May be

8.    Which of the following does bacteria need to assist it to grow and multiply;

A.    Water

B.     Food

C.     Warm temperatures

D.    All of the above

9.    How do you know if a beef burger has been properly cooked and is safe to eat?

A.    After cutting it in half and you see the inside as red you know it has been cooked properly.

B.     If you can see that it has been burnt then you know it is safe.

C.     If you can see the outside of the burger is evenly brown and when you cut it in the middle you can see that the meat is no longer pink.

10.                   Food contaminated with food poisoning bacteria would;

A.    Look different

B.     Smell badly

C.     Look and taste normal

D.    Generally speaking food poisoning bacteria cannot be smelled, tasted or seen (except with the aid of a microscope) on food.

11.                        Which of the following meats are safe to eat when they are pink or raw?

A.    Chicken

B.     Pork

C.     Minced meat

D.    Lamb                                          

12.                        Which one of the following jewellery is acceptable for a food handler to wear?

A.    Plain wedding band

B.     Arm ring

C.     Bracelet

D.    A ring that is a symbol of religious faith

13.                        You must wash poultry and chicken pieces before cooking them.

A.    True

B.     False

C.     Can’t say

D.    May be

14.                        How many times can you reheat leftovers?

A.    Many times

B.     Twice

C.    Four times

D.     Only once

15.                        How can you tell if food has enough bacteria to cause food poisoning?

A.    It will smell.

B.     You can’t, it will appear normal.

C.     It will have a different colour.

D.    It will taste different

                                           

16.                        What is the ideal temperature for Pathogens to flourish?

A.    10 degrees

B.     37 degrees

C.     55 degrees

D.    90 degrees                        

17.                        Where should raw meat be stored in a refrigerator?

A.    At the top.

B.     In the middle.

C.     At the bottom, below all other food

Answer the following.

1.      Which federal agency prepared the model FDA food code? Food and drug administration.

2.      Which federal agency is responsible for ensuring the safety of domestic meat, poultry, and egg products? US department of agriculture.

3.      Which federal agency is responsible for ensuring the safety of all the foods except domestic meat, poultry, and egg products? FDA

4.      Which federal agency is responsible for regulation on safety noice and other working condition? OSHA

5.      When a suspected food borne illness claim is reported to a wait-person, what should be the first course of action? Locate the food manager and ensure that the suspect food is not served.

6. Write a short note on storage of cheeses.

7.      Maintaining food quality depends on what factor?

8.      What are the forms in which foods come?

9.      Define shell-life.

10. Enumerate the purpose of storing food?

11. Write a note on storing perishable foods?

12. What are the general rules for reheating food?

13.  Enumerate the purpose of storing food.

ANSWERS KEYS

1.      C.    -18 ° or lower.

2.      A.     Frozen raw chicken.

3.      A.     Bacteria multiply and grow faster in warm environments.

4.      B.     1° and 4 °.

5.      B.     The power of arrest.

6.      A.      It helps to prevent food poisoning

7.      B. FALSE - Although the surface may be cooked, the centre may not be. It is important to ensure that all food is thoroughly cooked all the way through.

8.      D.

9.      C.     If you can see the outside of the burger is evenly brown and when you cut it in the middle you can see that the meat is no longer pink.

10.  D.     Generally speaking food poisoning bacteria cannot be smelled, tasted or seen (except with the aid of a microscope) on food. 

11.  D.     Lamb - It’s fine to eat steaks and other whole cuts of beef and lamb rare, as long as the outside has been properly cooked or ‘sealed’.

12.  A.

13.  B. FALSE - unless there is visible evidence or contamination like dirt or feathers etc.

14.  D.     You should only reheat leftovers once, and when doing so make sure that you reheat items thoroughly.

15.  B.     You can’t, it will appear normal correct - contaminated food CANNOT be identified by smell, taste or looks (unless it’s under a microscope).

16.  B.    

17.  C.     At the bottom, below all other food. (it should be covered to stop juices dripping from it onto other food stuff).