Food hygiene

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					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 &   Typoid fever, paratyphoid fever,
intoxications)                     Salmonellosis, Staphyloccal
                                   Cl. perfringens illness Botulism
                                   b. cereus Food Poisoning
                                   e. coli diarrhoea
                                   non-cholera vibrio illness
                                   V. parahaemolyticus - infection,
                                   streptococcal infection, Shigellosis,
Viral diseases                     Viral hepatitis, Gastroenteritis

 Parasites                         Taeniasis, Hydatidosis, Trichinosis,
                                   Ascariasis, Amoebiasis, Oxyuriasis
Classification of Food – borne Illnesses

Chemical poisons       Pesticides, heavy metals
                       (arsenic, lead, cadmium,

Food toxins            Lathyrism, Epidemic dropsy,
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
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
•   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.

•       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
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
 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 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

•      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 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.

• (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 self-closing 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.
• ) 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 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.

• 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‟.

•         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 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

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