Download Food hygiene

Food Hygiene
 Food is a potential source of infection and is liable to
contamination by microorganisms, at any point during its
journey from the producer to the consumer. Food
hygiene, in its widest sense, implies hygiene in the
production, handling, distribution and serving of all
types of food. The primary aim of food hygiene is to
prevent food poisoning and other food-borne illnesses,
which can be grouped under the following headings.
 The importance of surveillance of food-borne diseases has
been underlined in the WHO Sixth General Program of
Work . The most important international program carrying
out activities in the field of food hygiene is the Joint
FAO/WHO food Standards Program
Classification of Food – borne Illnesses
Bacterial diseases (infections &
intoxications)
Viral diseases
Parasites
Typoid fever, paratyphoid fever,
Salmonellosis, Staphyloccal
intoxication,
Cl. perfringens illness Botulism
b. cereus Food Poisoning
e. coli diarrhoea
non-cholera vibrio illness
V. parahaemolyticus - infection,
streptococcal infection, Shigellosis,
Brucellosis
Viral hepatitis, Gastroenteritis
Taeniasis, Hydatidosis, Trichinosis,
Ascariasis, Amoebiasis, Oxyuriasis
Classification of Food – borne Illnesses
Chemical poisons
Pesticides, heavy metals
(arsenic, lead, cadmium,
etc.)
Food toxins
Lathyrism, Epidemic dropsy,
Aflatoxins
Milk Hygiene
 Milk is an efficient vehicle for a great variety of disease
agents: The sources of infection or contamination of milk
may be (1) The dairy animal (2) human handler or (3) the
environment, e.g., contaminated vessels, polluted water,
flies, dust, etc.
Milkborne Diseases










A joint FAO/WHO Expert Committee on milk hygiene classified milk born diseases:
1.
Infections of animals that can be transmitted to man:
Primary importance –
Tuberculosis
Brucellosis
Streptococcal infections
Staphylococcal enterotoxin poisoning
Salmonellosis
Q Fever
Milk born diseases
 Lesser importance –





Cowpox
Foot and mouth disease
Anthrax
Leptospirosis
Tick-borne encephalitis











Infections primary to man tat can be transmitted through milk:
Typhoid and paratyphoid fevers
Shigellosis
Cholera
Enteropathogenic Escherichi coli
Non-diarrhoeal diseases
Streptococcal infections
Staphylococcal food poisoning
Diphtheria
Tuberculosis
Enteroviruses
Viral hepatitis
Clean and Safe Milk

The safety and keeping quality of milk are related to
its microbial content. The first essential in the
production of clean and safe milk, therefore, is a healthy
and clean animal. Milk from a healthy udder contains
only a few organisms, and these are relatively
unimportant. Secondly, the premises where the animal
is housed and milked should be sanitary. The milk vessels
must be sterile and kept covered. The water supply must
be bacteriologicaly safe.
 Milk handler must be free from communicable diseases,
and before milking they must wash their hands and arms.
Where possible, milking machines must be used. Milk
should be cooled immediately to below 10°C after it is
drawn to retard bacterial growth. In the production of
good quality milk, cleanliness of all containers and
equipment in which milk is handled is very important.
Pasteurization of milk
 Pasteurization may be defined as the heating of milk to
such temperatures and for such periods of time as are
required to destroy any pathogens that may be present
while causing minimal changes in the composition, flavor
and nutritive value (WHO). There are several methods
of pasteurization.
 Milk is kept at 63-66°C for at least 30 minutes, and then
quickly cooled to 5°C.
 “High Temperature and Short Time Method” Milk is rapidly heated
to a temperature of nearly 72°C, is held at that temperature for
not less than 15 seconds, and is then rapidly cooled to 4°C. This is
now the most widely method. Very large quantities of milk per
hour can be pasteurized by this method. (3) UHT Method: Also
known as “Utra High Temperature Method”. Milk is rapidly heated
usually in 2 stages (the second stage usually being under pressure)
to between 125°C, for a few seconds only. It is then rapidly
cooled and bottled as quickly as possible.
MEAT HYGIENE

The term “meat” includes various tissues of animal
origin. The diseases which may be transmitted by eating
unwholesome meat are: (1) TAPE WORM INFESTATIONS:
Tinea soliu, T. saginata, Trichinella spiralis and anthrax,
actinomycosis, tuberculosis and food poisoning.
Meat Inspection
 Animals intended for slaughter are subjected to proper
antemortem and postmortem inspection by qualified veterinary
staff. The principal causes of antemortem rejection of animals are
emaciation, exhaustion, pregnancy, sheep-pox, foot-rot,
actinomycosis, brucellosis, febrile conditions, diarrhoea and other
diseases of an infectious nature rendering meat unfit for human
consumption. The main causes of the postmortem rejection are
cysticercus bovis, liver fluke, abscesses, sarcocystis, hydatidosis,
septicaemia, parasitic and nodular infections of liver and lungs,
tuberculosis, cysticercus cellulosae, etc…(112). The
characteristics of good meat are that it should be neither pale pink
nor a deep purple tint, firm and elastic to touch, should not be
slimy and have an agreeable
Slaughter Houses
Location: Preferably away from residential areas.
Structure: Floors and walls up to 3 feet should be impervious and easy to clean.
Disposal of wastes: Blood, offal, etc… should not be discharged into public sewers but
should be collected separately.
Water Supply: should be independent, adequate and continuous.
Examination of animals: Antemortem and postmortem examination to be arranged.
Animals or meat found unfit for human consumption should be destroyed or
denatured.
Miscellaneous: animals other than those to be slaughtered should not be allowed inside the
shed.
Storage of meat: Meat should be stored in fly-proof and rat-proof rooms; for overnight
storage, the temperature of the room shall be maintained below 5°C. 8)
Transportation of meat: Meat shall be transported in fly-proof covered vans.
Fish
 Fish deteriorates or loses its freshness because of autolysis
which sets in after death and because of the bacteria with
which they become infected. Stale fish should be
condemned. The signs of fresh fish: 1) it is in a state of
stiffness or rigor mortis, 2) the gills are a bright red and 3)
the eyes are clear and prominent
EGG

Although the majority of freshly laid eggs are sterile
inside, the shells become contaminated by faecal matter from
the hen. Microorganisms including pathogenic Salmonella
can penetrate a cracked shell and enter the egg(48).
FRUITS AND VEGETABLES
 Fruits and vegetables constitute another important source for the
spread of pathogenic organisms, protozoan and helminthes. 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
then raw. Vegetables which are cooked and eaten are free from
this danger.
SANITATION OF EATING PLACES
 (1) Location: Shall not be near filth or open drain, stable, manure
pit and other sources of nuisances.
 (2) Floors: To be higher than the adjoining land, made with
impervious material and easy to keep clean.
 (3) Rooms: (a) Rooms where meals are served shall not be less
than 100 sq. feet and shall provide accommodation for a maximum
of 10 persons. (b) Walls up to 3 feet should be smooth, corners
to be rounded; should be impervious and easily washable.
 c) Lighting and ventilation – ample natural lighting facilities aided
by artificial lighting with good circulation of air are necessary.
 (4) Kitchen: (a) Floor space minimum 60 sq. ft. (b) window
opening to be 25 percent of floor area. (c) Floor to be
impervious, smooth, easy to keep clean and non-slippery. (d)
Doors and windows to be rat-proof, fly-proof, and of the selfclosing type. (e) Ventilators 2 percent of the floor area, in
addition to smoke pipes.
 (5) Storage of cooked food: Separate room to be provided. For long
storage, control of temperature is necessary.
 (6) Storage of uncooked foodstuffs. Perishable and non-perishable
articles to be kept separately in rat-proof and vermin-proof space;
for storage of perishable articles temperature control should be
adopted.
 (7) Furniture: Should be reasonably strong and easy to
keep clean and dry.
 (8) Disposal of refuse: To be collected in covered,
impervious bins and disposed of twice a day.
 (9)Water supply: To be an independent source, adequate,
continuous and safe.
 (10)Washing facilities: To be provided. Cleaning of
utensils and crockery to be done in hot water and
followed by disinfection.
Food Handlers
 Food sanitation rests directly upon the state of personal hygiene
and habits of the personnel working in the food establishments.
Proper handling of foods, utensils and dishes together with
emphasis upon the necessity for good personal hygiene are of
great importance. The infections which are likely to be
transmitted by the food handlers are diarrheas, dysenteries,
typhoid and para-typhoid fevers, entero-viruses, viral hepatitis,
protozoa cysts, eggs of helminthes, strepto and staphylococcal
infections and salmonellosis.
 The first essential is to have a complete medical examination
carried out of all food handlers at the time of employment. Any
person with a history of typhoid fever, diphtheria, chronic
dysentery, tuberculosis or any other communicable disease should
not be employed. Persons with wounds, otitis media or skin
infections should not be permitted to handle food or utensils. The
day to day health appraisal of the food handlers is also equally
important; those who are ill should be excluded from food
handling. It is also important that any illness which occurs in a
food handler's family should at once be notified.
 Education of food handlers in matters of personal hygiene, food
handling, utensils, dishwashing, and insect and rodent control is
the best means of promoting food hygiene. Many of the food
handlers have little educational background. Certain aspects of
personal hygiene are therefore required to be continually
impressed upon then: (a) Hands: The hands should be clean at all
times. Hands should be scrubbed and washed with soap and water
immediately after visiting a lavatory and as often as necessary at
other times. Fingernails should be kept trimmed and free from
dirt. (b) Hair: Head covering should be provided particularly in
the case of females to prevent loose hair obtaining entrance to
food-stuffs. (c) Overalls: Clean white overalls should be worn by
all food handlers. (d) Habits: Coughing and sneezing in the
vicinity of food, licking the fingers before picking up an article of
food, smoking on food premises are to be avoided.
ADULTERATION OF FOODS
 Adulteration of foods consists of a large number of
practices - mixing substitution, abstraction, concealing
the quality, putting up decomposed foods for sale,
misbranding or giving labels and addition of poisons.
Some forms of adulteration are injurious to health, eg.,
adulteration of mustard oil with argemone oil. But for
the most part food adulteration has an economic rather
than a sanitary significance eg., addition of water to
milk.
FOOD FORTIFICATION
 the process whereby nutrients are added to foods to maintain
or improve the quality of the diet of a group, a community or
a population’.
FOOD ADDITIVES

The concept of adding “non-food’ substances to food
products is not new. Pickling is an ancient culinary practice aimed
at preserving food articles such as mango, lime and amla for fairly
long periods by the addition of salt and spices. Modern science of
food technology employs more than 3,000 substances – some
natural (eg., saffron, turmeric) and others artificial or synthetic
(eg., saccharin, sorbic acid) known as ‘food additives’. Majority of
the processed foods such as bread, biscuits, cakes, sweets,
confectionary, jams, jellies, soft drinks, ketchup, all contain food
additives.
FOOD ADDITIVES
 Food additives are defined as non-nutritious substances which are added
intentionally to food, generally in small quantity, to improve its appearance,
flavour, texture or storage properties (116). The definition also includes animal
food adjuncts which may result in residues in human food and components of
packing materials which may find their way into food (117).
 The food additives may be classified as colouring agents (eg., saffron, turmeric),
flavouring agents (eg., vanilla essence), sweeteners (eg., saccarin), preservatives
(eg., sorbic acid, sodium benzoate), bleaching agents (eg., chlorine) acidity
imparting agents (eg., citric acid acetic acid), etc..(115). Uncontrolled or
indiscriminate use of food additives may pose health hazards among consumers.