Food hygieneFood hygiene

• Food is a potential source of infection and is Food is a potential source of infection and is liable to contamination by microorganisms, liable to contamination by microorganisms, at any point during its journey from the at any point during its journey from the producer to the consumer. Food hygiene, producer to the consumer. Food hygiene, in its widest sense, implies hygiene in the in its widest sense, implies hygiene in the production, handling, distribution and production, handling, distribution and serving of all types of food. The primary serving of all types of food. The primary aim of food hygiene is to prevent food aim of food hygiene is to prevent food poisoning and other food-borne illnesses, poisoning and other food-borne illnesses, which can be grouped under the following which can be grouped under the following headings.headings.

• The importance of surveillance of The importance of surveillance of food-borne diseases has been food-borne diseases has been underlined in the WHO Sixth General underlined in the WHO Sixth General Program of Work . The most Program of Work . The most important international program important international program carrying out activities in the field of carrying out activities in the field of food hygiene is the Joint FAO/WHO food hygiene is the Joint FAO/WHO food Standards Programfood Standards Program

Classification of Food – borne IllnessesClassification of Food – borne Illnesses Bacterial diseases (infections & Bacterial diseases (infections & intoxications)intoxications)

Typoid fever, paratyphoid fever, Typoid fever, paratyphoid fever, Salmonellosis, Staphyloccal Salmonellosis, Staphyloccal intoxication, intoxication,

Cl. perfringens Cl. perfringens illness Botulismillness Botulism

b. cereusb. cereus Food Poisoning Food Poisoning

e. colie. coli diarrhoea diarrhoea

non-cholera vibrio illnessnon-cholera vibrio illness

V. V. parahaemolyticusparahaemolyticus - infection, - infection, streptococcal infection, streptococcal infection, Shigellosis, BrucellosisShigellosis, Brucellosis

Viral diseasesViral diseases Viral hepatitis, GastroenteritisViral hepatitis, Gastroenteritis

ParasitesParasites Taeniasis, Hydatidosis, Taeniasis, Hydatidosis, Trichinosis, Ascariasis, Trichinosis, Ascariasis, Amoebiasis, OxyuriasisAmoebiasis, Oxyuriasis

Classification of Food – borne IllnessesClassification of Food – borne Illnesses

Chemical poisonsChemical poisons Pesticides, heavy metals Pesticides, heavy metals (arsenic, lead, cadmium, (arsenic, lead, cadmium, etc.)etc.)

Food toxinsFood toxins Lathyrism, Epidemic Lathyrism, Epidemic dropsy, Aflatoxinsdropsy, Aflatoxins

Milk HygieneMilk Hygiene

• Milk is an efficient vehicle for a great Milk is an efficient vehicle for a great variety of disease agents: The variety of disease agents: The sources of infection or contamination sources of infection or contamination of milk may be (1) The dairy animal of milk may be (1) The dairy animal (2) human handler or (3) the (2) human handler or (3) the environment, e.g., contaminated environment, e.g., contaminated vessels, polluted water, flies, dust, vessels, polluted water, flies, dust, etc.etc.

Milkborne DiseasesMilkborne Diseases

• A joint FAO/WHO Expert Committee on milk hygiene A joint FAO/WHO Expert Committee on milk hygiene classified milk -born diseases:classified milk -born diseases:

• 1.1. Infections of animals that can be transmitted to Infections of animals that can be transmitted to man:man:

• Primary importance –Primary importance –• TuberculosisTuberculosis• BrucellosisBrucellosis• Streptococcal infectionsStreptococcal infections• Staphylococcal enterotoxin poisoningStaphylococcal enterotoxin poisoning• SalmonellosisSalmonellosis• Q FeverQ Fever•

Milk born diseasesMilk born diseases

• Lesser importance – Lesser importance –

• CowpoxCowpox

• Foot and mouth diseaseFoot and mouth disease

• AnthraxAnthrax

• LeptospirosisLeptospirosis

• Tick-borne encephalitisTick-borne encephalitis

Infections primary to man tat can be transmitted through Infections primary to man tat can be transmitted through milk:milk:

• Typhoid and paratyphoid feversTyphoid and paratyphoid fevers• ShigellosisShigellosis• CholeraCholera• Enteropathogenic Escherichi coli Enteropathogenic Escherichi coli • Non-diarrhoeal diseasesNon-diarrhoeal diseases• Streptococcal infectionsStreptococcal infections• Staphylococcal food poisoningStaphylococcal food poisoning• DiphtheriaDiphtheria• TuberculosisTuberculosis• EnterovirusesEnteroviruses• Viral hepatitisViral hepatitis

Clean and Safe MilkClean and Safe Milk

• The safety and keeping quality of milk The safety and keeping quality of milk are related to its microbial content. The first are related to its microbial content. The first essential in the production of clean and safe essential in the production of clean and safe milk, therefore, is a healthy and clean milk, therefore, is a healthy and clean animal. Milk from a healthy udder contains animal. Milk from a healthy udder contains only a few organisms, and these are only a few organisms, and these are relatively unimportant. Secondly, the relatively unimportant. Secondly, the premises where the animal is housed and premises where the animal is housed and milked should be sanitary. The milk vessels milked should be sanitary. The milk vessels must be sterile and kept covered. The water must be sterile and kept covered. The water supply must be bacteriologicaly safe. supply must be bacteriologicaly safe.

• Milk handler must be free from Milk handler must be free from communicable diseases, and before milking communicable diseases, and before milking they must wash their hands and arms. they must wash their hands and arms. Where possible, milking machines must be Where possible, milking machines must be used. Milk should be cooled immediately to used. Milk should be cooled immediately to below 10°C after it is drawn to retard below 10°C after it is drawn to retard bacterial growth. In the production of good bacterial growth. In the production of good quality milk, cleanliness of all containers quality milk, cleanliness of all containers and equipment in which milk is handled is and equipment in which milk is handled is very important.very important.

Pasteurization of milkPasteurization of milk

• Pasteurization may be defined as the Pasteurization may be defined as the heating of milk to such temperatures heating of milk to such temperatures and for such periods of time as are and for such periods of time as are required to destroy any pathogens that required to destroy any pathogens that may be present while causing minimal may be present while causing minimal changes in the composition, flavor and changes in the composition, flavor and nutritive value (WHO). There are several nutritive value (WHO). There are several methods of pasteurization. methods of pasteurization.

• Milk is kept at 63-66°C for at least 30 Milk is kept at 63-66°C for at least 30 minutes, and then quickly cooled to 5°C. minutes, and then quickly cooled to 5°C.

• “ “High Temperature and Short Time Method” High Temperature and Short Time Method” Milk is rapidly heated to a temperature of Milk is rapidly heated to a temperature of nearly 72°C, is held at that temperature for not nearly 72°C, is held at that temperature for not less than 15 seconds, and is then rapidly less than 15 seconds, and is then rapidly cooled to 4°C. This is now the most widely cooled to 4°C. This is now the most widely method. Very large quantities of milk per hour method. Very large quantities of milk per hour can be pasteurized by this method. can be pasteurized by this method. (3)(3) UHT UHT Method: Also known as “Utra High Method: Also known as “Utra High Temperature Method”. Milk is rapidly heated Temperature Method”. Milk is rapidly heated usually in 2 stages (the second stage usually usually in 2 stages (the second stage usually being under pressure) to between 125°C, for a being under pressure) to between 125°C, for a few seconds only. It is then rapidly cooled and few seconds only. It is then rapidly cooled and bottled as quickly as possible.bottled as quickly as possible.

MEAT HYGIENEMEAT HYGIENE

• The term “meat” includes The term “meat” includes various tissues of animal origin. The various tissues of animal origin. The diseases which may be transmitted diseases which may be transmitted by eating unwholesome meat are: (1) by eating unwholesome meat are: (1) TAPE WORM INFESTATIONS: Tinea TAPE WORM INFESTATIONS: Tinea soliu, T. saginata, Trichinella spiralis soliu, T. saginata, Trichinella spiralis and anthrax, actinomycosis, and anthrax, actinomycosis, tuberculosis and food poisoning.tuberculosis and food poisoning.

Meat InspectionMeat Inspection

• Animals intended for slaughter are subjected to proper Animals intended for slaughter are subjected to proper antemortem and postmortem inspection by qualified antemortem and postmortem inspection by qualified veterinary staff. The principal causes of antemortem veterinary staff. The principal causes of antemortem rejection of animals are emaciation, exhaustion, pregnancy, rejection of animals are emaciation, exhaustion, pregnancy, sheep-pox, foot-rot, actinomycosis, brucellosis, febrile sheep-pox, foot-rot, actinomycosis, brucellosis, febrile conditions, diarrhoea and other diseases of an infectious conditions, diarrhoea and other diseases of an infectious nature rendering meat unfit for human consumption. The nature rendering meat unfit for human consumption. The main causes of the postmortem rejection are cysticercus main causes of the postmortem rejection are cysticercus bovis, liver fluke, abscesses, sarcocystis, hydatidosis, bovis, liver fluke, abscesses, sarcocystis, hydatidosis, septicaemia, parasitic and nodular infections of liver and septicaemia, parasitic and nodular infections of liver and lungs, tuberculosis, cysticercus cellulosae, etc…(112). The lungs, tuberculosis, cysticercus cellulosae, etc…(112). The characteristics of good meat are that it should be neither characteristics of good meat are that it should be neither pale pink nor a deep purple tint, firm and elastic to touch, pale pink nor a deep purple tint, firm and elastic to touch, should not be slimy and have an agreeable should not be slimy and have an agreeable

Slaughter HousesSlaughter Houses

Location: Preferably away from residential areas. Location: Preferably away from residential areas. Structure: Floors and walls up to 3 feet should be impervious and Structure: Floors and walls up to 3 feet should be impervious and

easy to clean. easy to clean. Disposal of wastes: Blood, offal, etc… should not be discharged into Disposal of wastes: Blood, offal, etc… should not be discharged into

public sewers but should be collected separately. public sewers but should be collected separately. Water Supply: should be independent, adequate and continuous. Water Supply: should be independent, adequate and continuous. Examination of animals: Antemortem and postmortem examination Examination of animals: Antemortem and postmortem examination

to be arranged. Animals or meat found unfit for human to be arranged. Animals or meat found unfit for human consumption should be destroyed or denatured. consumption should be destroyed or denatured.

Miscellaneous: animals other than those to be slaughtered should Miscellaneous: animals other than those to be slaughtered should not be allowed inside the shed. not be allowed inside the shed.

Storage of meat: Meat should be stored in fly-proof and rat-proof Storage of meat: Meat should be stored in fly-proof and rat-proof rooms; for overnight storage, the temperature of the room shall rooms; for overnight storage, the temperature of the room shall be maintained below 5be maintained below 5°°C. 8) Transportation of meat: Meat shall C. 8) Transportation of meat: Meat shall be transported in fly-proof covered vans.be transported in fly-proof covered vans.

FishFish

• Fish deteriorates or loses its freshness Fish deteriorates or loses its freshness because of autolysis which sets in after because of autolysis which sets in after death and because of the bacteria with death and because of the bacteria with which they become infected. Stale fish which they become infected. Stale fish should be condemned. The signs of should be condemned. The signs of fresh fish: 1) it is in a state of stiffness fresh fish: 1) it is in a state of stiffness or rigor mortis, 2) the gills are a bright or rigor mortis, 2) the gills are a bright red and 3) the eyes are clear and red and 3) the eyes are clear and prominentprominent

EGGEGG

• Although the majority of freshly Although the majority of freshly laid eggs are sterile inside, the shells laid eggs are sterile inside, the shells become contaminated by faecal become contaminated by faecal matter from the hen. matter from the hen. Microorganisms including pathogenic Microorganisms including pathogenic Salmonella can penetrate a cracked Salmonella can penetrate a cracked shell and enter the egg(48).shell and enter the egg(48).

FRUITS AND FRUITS AND VEGETABLESVEGETABLES

• Fruits and vegetables constitute another Fruits and vegetables constitute another important source for the spread of pathogenic important source for the spread of pathogenic organisms, protozoan and helminthes. These organisms, protozoan and helminthes. These infections are a serious menace to public health infections are a serious menace to public health where sewage is used for growing vegetables. where sewage is used for growing vegetables. The vegetables which are consumed raw in the The vegetables which are consumed raw in the form of salads pose a problem in food sanitation. form of salads pose a problem in food sanitation. People should be educated to wash the People should be educated to wash the vegetables before eating then raw. Vegetables vegetables before eating then raw. Vegetables which are cooked and eaten are free from this which are cooked and eaten are free from this danger.danger.

SANITATION OF EATING PLACESSANITATION OF EATING PLACES

• (1) Location: (1) Location: Shall not be near filth or open Shall not be near filth or open drain, stable, manure pit and other sources of drain, stable, manure pit and other sources of nuisances. nuisances.

• (2) Floors:(2) Floors: To be higher than the adjoining land, To be higher than the adjoining land, made with impervious material and easy to keep made with impervious material and easy to keep clean. clean. ((

• 3) Rooms:3) Rooms: (a) Rooms where meals are served (a) Rooms where meals are served shall not be less than 100 sq. feet and shall shall not be less than 100 sq. feet and shall provide accommodation for a maximum of 10 provide accommodation for a maximum of 10 persons. (b) Walls up to 3 feet should be persons. (b) Walls up to 3 feet should be smooth, corners to be rounded; should be smooth, corners to be rounded; should be impervious and easily washable. (impervious and easily washable. (

• c) Lighting and ventilation – ample natural lighting facilities c) Lighting and ventilation – ample natural lighting facilities aided by artificial lighting with good circulation of air are aided by artificial lighting with good circulation of air are necessary. necessary. (4) Kitchen:(4) Kitchen: (a) Floor space minimum 60 sq. ft. (a) Floor space minimum 60 sq. ft. (b) window opening to be 25 percent of floor area. (c) (b) window opening to be 25 percent of floor area. (c) Floor to be impervious, smooth, easy to keep clean and Floor to be impervious, smooth, easy to keep clean and non-slippery. (d) Doors and windows to be rat-proof, fly-non-slippery. (d) Doors and windows to be rat-proof, fly-proof, and of the self-closing type. (e) Ventilators 2 proof, and of the self-closing type. (e) Ventilators 2 percent of the floor area, in addition to smoke pipes. percent of the floor area, in addition to smoke pipes. (5) (5) Storage of cooked food:Storage of cooked food: Separate room to be provided. For Separate room to be provided. For long storage, control of temperature is necessary. long storage, control of temperature is necessary. (6) (6) Storage of uncooked foodstuffs.Storage of uncooked foodstuffs. Perishable and non- Perishable and non-perishable articles to be kept separately in rat-proof and perishable articles to be kept separately in rat-proof and vermin-proof space; for storage of perishable articles vermin-proof space; for storage of perishable articles temperature control should be adopted. temperature control should be adopted.

• ) Furniture:) Furniture: Should be reasonably strong Should be reasonably strong and easy to keep clean and dry. and easy to keep clean and dry. (8) (8) Disposal of refuse:Disposal of refuse: To be collected in To be collected in covered, impervious bins and disposed of covered, impervious bins and disposed of twice a day. twice a day. (9) Water supply:(9) Water supply: To be an To be an independent source, adequate, continuous independent source, adequate, continuous and safe. and safe. (10) Washing facilities: (10) Washing facilities: To be To be provided. Cleaning of utensils and crockery provided. Cleaning of utensils and crockery to be done in hot water and followed by to be done in hot water and followed by disinfection.disinfection.

Food HandlersFood Handlers

• Food sanitation rests directly upon the state of Food sanitation rests directly upon the state of personal hygiene and habits of the personnel personal hygiene and habits of the personnel working in the food establishments. Proper working in the food establishments. Proper handling of foods, utensils and dishes together handling of foods, utensils and dishes together with emphasis upon the necessity for good with emphasis upon the necessity for good personal hygiene are of great importance. The personal hygiene are of great importance. The infections which are likely to be transmitted by infections which are likely to be transmitted by the food handlers are diarrheas, dysenteries, the food handlers are diarrheas, dysenteries, typhoid and para-typhoid fevers, entero-viruses, typhoid and para-typhoid fevers, entero-viruses, viral hepatitis, protozoa cysts, eggs of viral hepatitis, protozoa cysts, eggs of helminthes, strepto and staphylococcal infections helminthes, strepto and staphylococcal infections and salmonellosis.and salmonellosis.

• The first essential is to have a complete medical The first essential is to have a complete medical examination carried out of all food handlers at the examination carried out of all food handlers at the time of employment. Any person with a history of time of employment. Any person with a history of typhoid fever, diphtheria, chronic dysentery, typhoid fever, diphtheria, chronic dysentery, tuberculosis or any other communicable disease tuberculosis or any other communicable disease should not be employed. Persons with wounds, should not be employed. Persons with wounds, otitis media or skin infections should not be otitis media or skin infections should not be permitted to handle food or utensils. The day to permitted to handle food or utensils. The day to day health appraisal of the food handlers is also day health appraisal of the food handlers is also equally important; those who are ill should be equally important; those who are ill should be excluded from food handling. It is also important excluded from food handling. It is also important that any illness which occurs in a food handler's that any illness which occurs in a food handler's family should at once be notified.family should at once be notified.

• Education of food handlers in matters of personal hygiene, Education of food handlers in matters of personal hygiene, food handling, utensils, dishwashing, and insect and rodent food handling, utensils, dishwashing, and insect and rodent control is the best means of promoting food hygiene. Many control is the best means of promoting food hygiene. Many of the food handlers have little educational background. of the food handlers have little educational background. Certain aspects of personal hygiene are therefore required Certain aspects of personal hygiene are therefore required to be continually impressed upon then: (a) Hands: The to be continually impressed upon then: (a) Hands: The hands should be clean at all times. Hands should be hands should be clean at all times. Hands should be scrubbed and washed with soap and water immediately scrubbed and washed with soap and water immediately after visiting a lavatory and as often as necessary at other after visiting a lavatory and as often as necessary at other times. Fingernails should be kept trimmed and free from times. Fingernails should be kept trimmed and free from dirt. (b) Hair: Head covering should be provided dirt. (b) Hair: Head covering should be provided particularly in the case of females to prevent loose hair particularly in the case of females to prevent loose hair obtaining entrance to food-stuffs. (c) Overalls: Clean white obtaining entrance to food-stuffs. (c) Overalls: Clean white overalls should be worn by all food handlers. (d) Habits: overalls should be worn by all food handlers. (d) Habits: Coughing and sneezing in the vicinity of food, licking the Coughing and sneezing in the vicinity of food, licking the fingers before picking up an article of food, smoking on fingers before picking up an article of food, smoking on food premises are to be avoided.food premises are to be avoided.

ADULTERATION OF FOODSADULTERATION OF FOODS

• Adulteration of foods consists of a large Adulteration of foods consists of a large number of practices - mixing substitution, number of practices - mixing substitution, abstraction, concealing the quality, putting abstraction, concealing the quality, putting up decomposed foods for sale, misbranding up decomposed foods for sale, misbranding or giving labels and addition of poisons. or giving labels and addition of poisons. Some forms of adulteration are injurious to Some forms of adulteration are injurious to health, eg., adulteration of mustard oil with health, eg., adulteration of mustard oil with argemone oil. But for the most part food argemone oil. But for the most part food adulteration has an economic rather than a adulteration has an economic rather than a sanitary significance eg., addition of water sanitary significance eg., addition of water to milk.to milk.

FOOD FORTIFICATIONFOOD FORTIFICATION

• the process whereby nutrients are the process whereby nutrients are added to foods to maintain or added to foods to maintain or improve the quality of the diet of a improve the quality of the diet of a group, a community or a population’. group, a community or a population’.

FOOD ADDITIVESFOOD ADDITIVES

• The concept of adding “non-food’ substances The concept of adding “non-food’ substances to food products is not new. Pickling is an ancient to food products is not new. Pickling is an ancient culinary practice aimed at preserving food articles culinary practice aimed at preserving food articles such as mango, lime and amla for fairly long such as mango, lime and amla for fairly long periods by the addition of salt and spices. Modern periods by the addition of salt and spices. Modern science of food technology employs more than science of food technology employs more than 3,000 substances – some natural (eg., saffron, 3,000 substances – some natural (eg., saffron, turmeric) and others artificial or synthetic (eg., turmeric) and others artificial or synthetic (eg., saccharin, sorbic acid) known as ‘food additives’. saccharin, sorbic acid) known as ‘food additives’. Majority of the processed foods such as bread, Majority of the processed foods such as bread, biscuits, cakes, sweets, confectionary, jams, jellies, biscuits, cakes, sweets, confectionary, jams, jellies, soft drinks, ketchup, all contain food additives.soft drinks, ketchup, all contain food additives.

FOOD ADDITIVESFOOD ADDITIVES

• Food additives are defined as non-nutritious substances Food additives are defined as non-nutritious substances which are added intentionally to food, generally in small which are added intentionally to food, generally in small quantity, to improve its appearance, flavour, texture or quantity, to improve its appearance, flavour, texture or storage properties(116). The definition also includes animal storage properties(116). The definition also includes animal food adjuncts which may result in residues in human food food adjuncts which may result in residues in human food and components of packing materials which may find their and components of packing materials which may find their way into food(117).way into food(117).

• The food additives may be classified as colouring The food additives may be classified as colouring agents (eg., saffron, turmeric), flavouring agents (eg., agents (eg., saffron, turmeric), flavouring agents (eg., vanilla essence), sweeteners (eg., saccarin), preservatives vanilla essence), sweeteners (eg., saccarin), preservatives (eg., sorbic acid, sodium benzoate), bleaching agents (eg., (eg., sorbic acid, sodium benzoate), bleaching agents (eg., chlorine) acidity imparting agents (eg., citric acid acetic chlorine) acidity imparting agents (eg., citric acid acetic acid), etc..(115). Uncontrolled or indiscriminate use of food acid), etc..(115). Uncontrolled or indiscriminate use of food additives may pose health hazards among consumers.additives may pose health hazards among consumers.