Food is a potential source of infection. It is liable for contamination by micro-organisms; at any point during its journey from the producer to the consumer the mail danger from contamination arise from handling distribution and serving of foods. Food hygiene, in its widest sense implies hygiene in the production, handling, distribution and serving of all types of food.
Milk is an efficient vehicle for a great variety of disease agents. The sources of infection of milk may be (i) the diary of animal (ii) the human handler or (iii) the environment, e.g. contaminated vessels, polluted, water, flies, dust etc. But for the production of clean and safe milk the following factors should be taken in to consideration.
(i) Animal must be healthy and clean;
(ii) Premises where the animal is housed and milked must be sanitary;
(iii) The milk vessels must be sterile and kept covered.
(iv) The water supply must be safe.
(v) Milk handle’s must be free from communicable diseases.
(vi) Millkers must wash their hands and arms before milking.
(vii) The distribution of milk must be done under hygienic condition.
Much of the milk produced in India is treated by boiling but it has some ban effects Boiling alters the taste of milk and impairs the food values considerably owing to destruction of vitamins, enzymes and some useful bacteria and alteration of proteins, fats, milk, sugar and salts. So milk should be heated to a temperature of 161° F and cooled to below 50°F
The term meat includes various tissues of animal origin. The diseases which may be transmitted by eating unwholesome meat are: Tape worm integrations and Bacterial infestations causing anthrax, tuberculosis, and food poisoning.
The characteristics of good meat are that it should not be pale, pink or a deep purple tint, firm and elastic to touch, should not be slimy and have an agreeable odour.
Slaughter houses are the places where animals, whose flesh is intended for human consumption, are killed. The hygiene of the slaughter house is of paramount importance to prevent the contamination of meat during the process of dressing preferably the slaughter houses should be away from the residential areas and there must be provision for the disposal of wastes, proper water supply, examination of animals, storage of meat, transportation of meat etc.
Fish loses its freshness because of the bacteria with which they become infected. The signs of fresh fish are the stiffness, the bright red gills and the clear and prominent eyes Fish is the intermediate host of the tape worm. Fish obtained from sewage polluted waters may be infected with cholera and typhoid bacilli. Consumption of certain fish may sometimes give rise to fish poisoning.
Fruits and Vegetables:
Fruits and vegetables constitute another important source for the spread of harmful organisms these infections are a serious menace to public health where sewage is used for growing vegetables. The vegetables which are consumed raw in the form of salads, pose a problem in food sanitation. People should be educated to wash the vegetables before eating them raw. Vegetables which are cooked and eaten are free from this danger.
Sanitation of Kitchen:
Sanitation of Kitchen and eating establishment are a challenging problem in food sanitation. These should not be near any accumulation of filth or open drain, manure pit and other sources of nuisances the floor of the kitchen should be smooth and easy to keep clean. The doors and windows should be rat- proof, fly-proof, and of the self-closing type, there should be provision for ample natural lighting facilities aided by proper ventilation.
Preservation of Foods:
Generally food is preserved by freezing or by using currents of cold air. Cold storage is used for the preservation of foodstuffs and their conveyance from one place to another.
Food may also be preserve in ice, alcohol vinegar and by other substances drying is sometimes adopted to, as in the case of fish, vegetables and fruits. By the method of dehydration, vegetable can be preserved in a very small space for a long time and can be used for cooking by merely soaking in water for a while.
Foods like milk, fish, fruit and jams are also preserved in tins or bottles by proper sealing after all the air has been expelled by heat. Badly preserved foods are not conductive for health,
Adulteration of Foods:
Adulteration of food consists of a large number of practices such as mixing, substitution, abstraction, concealing the quality, putting up decomposed foods for sale, misbranding and addition of poisons. The types of adulteration commonly found in the various foodstuffs in India are as follows;
(i) Removal of fat and addition of water and milk powder are common type of milk adulteration;
(ii) Ghee is adulterated with vegetable oils and animal fats;
(iii) Rice and wheat are mixed with stone chips and gravel to increase bulk;
(iv) Wheat flour is mixed with soap stone powder and khesari dhal and pea flour;
(v) Tea leaves are adulterated with old tea leaves, leather and saw dust as well as coffee is with chicory;
Methods of Cooking:
Food may be boiled, steamed, roasted, and fried. The method of cooking food should be varied as much as possible; otherwise it will lose its result. Every attention should be paid to cleanliness. Cooking vessels made of aluminum are to be preferred to those made of copper.
Rice and other starch foods should be cooked slowly and green vegetables quickly with proper covering. Well-cooked rice is soft and free from lumps. Dhal should be very carefully husked and then cooked; otherwise it will cause irritation of the bowels. Separate room should be provided for storage of cooked foods. Water supply should be adequate continuous and safe. Cleaning of utensils and crockery should be done in hot ‘ water and followed by disinfection.
Food sanitation rests directly upon the state of personal hygiene and habits of the personnel working in the food establishments. Education of food handlers in matters of personal hygiene, food handling, utensil and dish washing is the best means of promoting food hygiene.
The hands should be cleaned at all times. Hands should be scrubbed and washed with soap and water immediately after visiting a lavatory.
Finger should be kept trimmed and free from dirt. Head covering should be provided to prevent loose hairs obtaining entrance to foodstuffs. Coughing and sneezing in the vicinity of food and smoking on food premises should be avoided.