ESTIMATION OF FOOD PRODUCTS

ESTIMATION OF FOOD PRODUCTS. A METHOD OF EXPERT ESTIMATION OF FOOD PRODUCTS AND PREPARED FOODS AS A RESULT OF THEIR LABORATORY ANALYSIS.

THEORETICAL ASPECTS AND METHOD OF PROPHYLAXIS OF ALIMENTARY AND ALIMENTARY PREDEFINED DISEASES. HYGIENICAL BASES OF MEDICAL - DIETIC AND TREATMENT –PROPHYLACTIC FEED. METHOD OF INVESTIGATION OF CASES OF THE FOOD POISONINGS.

Nutrition may be defined as the science  of food and its relationship to health. It is concerned primarily with the part played by nutrients in body growth,development and maintenance. The word nutrient or "food factor" is used for specific dietary constituents such as proteins, vitamins and minerals. Dietetics is  the practical application of the principles of nutrition; it includes   the planning of meals for the well and the sick. Good nutrition means "maintaining a nutritional status that enables us to grow well and enjoy good health". Maintaining a healthy diet is the practice of making choices about what to eat with the intent of improving or maintaining good health. Usually this involves consuming necessary nutrients by eating the appropriate amounts from all of the food groups. Since human nutrition is complex a healthy diet may vary widely subject to an individual's genetic makeup, environment, and health. For around 20% of the planet's population, lack of food and malnutrition are the main impediments to healthy eating.

http://en.wikipedia.org/wiki/Nutrition

Generally, a healthy diet will include:

1. Sufficient calories to maintain a person's metabolic and activity needs, but not so excessive as to result in fat storage greater than roughly 12% of body mass;

2. Sufficient fat, consisting mostly of mono- and polyunsaturated fats (avoiding saturated and "trans" fats) and with a balance of omega-6 and long-chain omega-3 lipids;

3. Sufficient essential amino acids ("complete protein") to provide cellular replenishment and transport proteins;

4. Essential micronutrients such as vitamins and certain minerals.

5. Avoiding directly poisonous (e.g. heavy metals) and carcinogenic (e.g. benzene) substances;

6. Avoiding foods contaminated by human pathogens (e.g. e. coli, tapeworm eggs);

7. Avoiding chronic high doses of certain foods that are benign or beneficial in small or occasional doses, such as

·         foods or substances with directly toxic properties at high chronic doses (e.g. ethyl alcohol, Vitamin A);

·        foods that may interfere at high doses with other body processes (e.g. table salt);

·        foods that may burden or exhaust normal functions (e.g. refined carbohydrates without adequate dietary fiber).

http://www.healthyliving.gov.uk/publications/pub_fulldoc.cfm?TxtTCode=1495

 

RELATION OF NUTRITION TO HEALTH

http://www.nutrition.com.sg/he/hepyr.asp

Good nutrition is a basic component of health. The relation of nutrition to health may be seen from the following view points:

Growth and development: Good nutrition is essential for the attainment of normal growth and development. Not only physical growth and development, but also the intellectual development, learning and behaviour are affected by malnutrition. Malnutrition during pregnancy may affect the foetus resulting in still-birth, premature birth and "small-for dates" babies. Malnutrition during early childhood delays physical and   mental growth; such children are slow in passing their "milestones", and are slow learners in school. Good nutrition is also essential in adult life for the maintenance of optimum health and efficiency. In short, nutrition affects human health from birth till death.

Specific deficiency: Malnutrition is directly responsible for certain specific nutritional deficiency diseases. The commonly reported ones in India are kwashiorkor, marasmus, blindness due to vitamin A  deficiency, anaemia, beriberi, goitre, etc. Good nutrition therefore   is essential for the prevention of specific nutritional deficiency diseases and promotion of health.

       Resistance to infection:

Malnutrition predisposes to infections like tuberculosis. It also influences the course and out-come of many a clinical disorder. Infection, in turn, may aggravate malnutrition by affecting the food intake, absorption and metabolism.

Mortality and morbidity:

The indirect effects of malnutrition on the community are even more striking - a high general death rate, high infant mortality rate, high sickness rate and a lower Expectation of life. Over-nutrition, which is another form of malnutrition is responsible for obesity, diabetes, hypertension, cardiovascular and renal disease, disorders of the liver and gall bladder. More recent reports suggest that diet perhaps plays an important role in certain types of gastro-intestinal cancers. It is now quite well accepted that diet and certain diseases are interrelated.

   Nutrition as a science can be regarded as the study of six main categories of food components: protein, carbohydrate, fat, minerals, vitamins, and water. The first three categories -protein, carbohydrate, and fat — are the only ones that provide calories. Protein provides 4 Calories/gm, as does carbohydrate. Fat provides slightly more than twice as much — 9 Calories/gm.vitamins and minerals.htm

Although minerals and vitamins provide no calories, they function in the many metabolic processes whereby one obtains and utilizes energy from foods and builds and then maintains body tissues. Minerals also function as vital constituents of many body tissues. Iron is a necessary component of hemo­globin, myoglobin, and the cytochromes, and calcium and fluoride are required for sound teeth and bones.

Water. It is an important constituent of food and in its absence, it is impossible to survive beyond a few days. It forms about 70% of body weight. Even bones contain about 20% of water. Water is necessary to make up the loss caused by its excretion in breath, sweat, urine, faeces, and also to renew all the various fluids and solid organs of the body.

 The amount of water needed by every individual generally varies depending upon the outside temperature or the extent up to which the human body is subjected to the manual labour. This rise of temperature and humidity of air increases the necessity for intake of water. An insufficient intake of water leads to creation of disturbance in circulation, of heat regulation mechanism and the retention of products of metabolism. On the other hand, abundant intake of drinking water promotes  the circulation of fluid and increases the activity of kidneys with free secretion of urine. It is estimated that about 80 oz (2.27 litres) of water enters the body daily as such or as a part of cooked food, beverages etc. Out of which 48-64 oz. (1.37- 1.81 litres) is excreted daily in urine, sweat etc.

Some important uses of water are:

- As a solvent for transportation of nutrients in the body.

- It   helps   regulating   body   temperature through evaporation from lungs and skin.

- As an aid in removing wastes of metabolism in the urine.

- As an aid in functions like osmosis.

 It is possible to allocate five groups of diseases, that is direct or mediate related with a nutrition:

1. Alimentary disease, illness caused by deficiency or surplus of components of nutrition.

2. The secondary illnesses of insufficiency or excessive nutrition, which is developed as complication on a background of wearisome illnesses (surgical, infectious, oncology and others.)

3. Disease of multifactor nature that very much frequently develops on a background of genetic predilection, for example, atherosclerosis, gout, idiopathic hypertensia, oncological diseases etc.  

4. Disease, which are transferred by a nutritional way (some infections and helminths, alimentary poisonings).

5. Alimentary intolerance - atypical reaction to nutrition, for example alimentary allergy, idiosyncrasy.  Fats.

FUNCTIONS OF FOOD:

The main functions of food are:-

1. Provision of energy - It provides fhe body fuels or energy foods, which on oxidation supply heat and energy. Even while at bed rest, some energy is being expended on respiratory, circulatory, and other body processes.

2. Body building and repair - It provides the material needed for growth  and upkeep of the body. Even after growth isstopped, the body continues to change throughout life. Tissues are continually wearing out and these must be changed or repaired.

3. Maintenance and regulation of tissue functions - It provides the materials which regulate and maintain body functions and processes. They regulate the way, in which various parts of the body act and protect the body from disease

On the basis of the above functions foods have been classified as :

(1) Energy-yielding foods: These are foods rich in carbohydrate and fat, e.g., rice, wheat, potatoes, sugar, fats and oils.

(2) Body building foods: These are foods rich in protein, e.g., milk, eggs, meat, liver, fish, pulses, oilseed cakes.

(3) Protective foods: These are foods rich in vitamins, minerals and proteins, e.g., milk, green leafy vegetables. Protective foods are so called because they protect the body against infection, disease and ill health.

A balanced diet must contain foods from the above three groups.

Balanced diet is one, which will meet a person's caloric need and contain all nutrients, particularly proteins, and vitamins. In addition, the food should satisfy the taste and desire of a person and should have enough roughage to promote the peristalsis. Balanced diet should have 50-60 % carbohydrates 30-35 % fats and 10-15 % proteins with necessary vitamins and minerals.

1. Conformity of entering energy to energy losses.

2. Conformity of chemical structure of alimentary substances to physiological needs of an organism.

3. The maximal variety of a ration.

4. Keeping of an optimum regimen of nutrition.

http://www.illumine.co.uk/course-fit-healthy-nutrition.htm

NUTRIENTS

Nutrients are organic and inorganic complexes contained in food. There are about 50 different nutrients which are normally supplied through the foods we eat. Each nutrient has specific functions in the body. Most natural foods contain more than one nutrient. These may be divided into :

(i) Macronutrients: These are proteins, fats and carbohydrates which are   often   called   "proximate   principles" because they form the main bulk of food.

 (ii) Micronutrients : These are vitamins and minerals. They are called micronutrients because they are required in small amounts which may vary from a fraction of a milligram to several grams.

A short review of basic facts about these nutrients is given below.

Animal Foods

These are, for example, e.g. meat, fish, eggs milk and milk products.

Animal Foods

These are, for example, e.g. meat, fish, eggs milk and milk products.

Meat

The nutritional value of meat is generally derived from its high protein content. The fats found in meats can also be a valuable source of fuel for the body. Meat typically contains important minerals, including iron, phosphorous, zinc, and the complete range of B vitamins, some of which — like vitamin B12 — can usually only be found in foods derived from animals.

Meat usually contains high levels of complete protein, a nutrient necessary for a healthy body. The proteins in meat are normally easy for most people to digest. The body typically uses this nutrient to perform cellular repairs and generate new tissue. Protein is also considered crucial to the regulation of immune function and electrolyte balance.

Fat is also found in meat, and while too much fat can be bad for health, some is needed to keep the body working correctly. The human body generally burns fat for energy. Protein can also be used for energy, but most experts agree that fat and carbohydrates should supply the bulk of the body's energy needs.

Iron is necessary for helping oxygen molecules bind to red blood cells, and meat is considered an excellent source of this mineral. The iron found in meats is among the most easily absorbed and used of any dietary sources. Vegetable sources of this mineral may be more difficult for the body to use.

Phosphorous and zinc also form part of the nutritional value of meat. Along with dairy products and fish, meat is considered a good source of dietary phosphorous, which helps to support bone health. Zinc, which helps regulate metabolism and enzyme function, can also be found in many meats.

B vitamins are some of the most crucial nutrients found in meat, since some of them can't usually be found in other foods. These vitamins help to support metabolic function, cognitive function, skin health, the production of red blood cells and digestion. Vitamin B12 in particular can typically only be found in meat and other animal-derived food products.

Though meat can form part of a healthy diet, many types contain high levels of fat andcholesterol and should not be eaten excessively. Lean meats are generally considered most nutritious. Consumers may be able to enjoy the maximum nutritional value of meat, with the lowest risk, by choosing lean meats and preparing them in a way that does not increase their fat and cholesterol levels.

Characteristics of Good Meat

1. It has marbelled appearance due to fat and is acidic.

2. It is firm and elastic to touch.

3. No oedema or bad odour.

4. It is dry on surface and does not shrink much on cooking.

Meat of Unsound Quality

1.     It is soft, moist and pale.

2.     Reaction is alkaline and has putrefied odour.

Following are some of the diseases produced by consumption of unsound meat.

1. Tuberculosis: Tuberculosis is common in cattle but rare in sheep and goats. Usually, lymphatic glands, lungs, and liver are affected, but not the muscles. Howevr, flesh of tubercular animal should always be condemned.

2. Food poisoning may be caused by tinned meat. Such tins should have no dents and their ends should be concave and not convex. On opening, air should rush out and contents should not be discoloured.

3. Cysticercosis: Embryos of tape-worms inhabit the muscle of pigs, ox, etc and such a meat when ingested causes tape worm infection. However, embryos are killed, if such a meat is properly cooked.

4. Trichenella spiralis: Embryos are usually encysted in pig meat.

5. Actinomycosis through ox-meat especially in damp climate. The affected portions should be condemned.

6. Liver flukes is common in liver of sheep. Cooking always kills the parasites.

Diseased Meat

         The flesh of animals killed by accident, lightning or those who happen to be suffering from diseases like anthrax, rabies, glanders, general tuberculosis etc., should be condemned. The diseased meat should be condemned and prevented from sending into the market.

The chief diseases of animals are:

(1)            Tuberculosis.

(2)            Cysticercus.

(3)            Trichinella Spiralis.

(4)            Actinomycosis or Ray Fungus.

(5)            Distomum Hepaticum of Liver Flukes.

 

Preventive Measures

1.     Compulsory inspection of animals before slaughtering and also of carcasses by veterinary experts at slaughter houses, which should be public owned.

2.     The slaughter houses should be pucca built with proper drainage and free water supply for cleaning. These should be situated away from habitation and no dogs, etc. should be allowed in the vicinity.

3.     Persons suffering from infectious diseases should not be al­lowed to handle meat.

4.     Meat at shops must be properly protected from flies.

5.     Vehicles for transporting meat must be clean.

Fish

It is highly nutritive and easily digested. It contains all vitamins (except Vit. C) and has high calcium value. Its liver is rich in Vit. A and D. Fresh fish has bright pink gills and firm shiny scales with prominent eyes. It is firm and elastic with no bad odour.

Fish is considered as 'brain food'. It contains omegas, a polyun-saturated fatty acid, which lowers blood pressure, relieves arthritis inflammation and aids brain development. Fish oils tend to lower blood cholesterol and triglycerides.

Fish poisoning may occur by toxin produced by Cl. botulinum and decomposed fish may cause protamine poisoning. Shell fish from polluted water contains toxins.

It is easily digested and is assimiable. It has a high nutritive value, though not so stimulating as meat, but generally it is less rich in fats and contains more calcium than ordinary meat. It has all the vitamins except vitamin C. Fish liver is a rich source of vitamins A and D. Sea fish is a rich source of iodine.

There are two kinds of fish: Lean fish. It consists of small fibres and contains fat below 2 %. It is easily digested. Fat fish. It consists of medium or large fibres with fat content of 2.5% or more. It is somewhat difficult to digest.

Characteristics of Good Fish A fish should have bright pink gills, firm glistening scales and prominent lustrous eyes. It should have a bright and glistening skin with a covering of clear slippery mucous. It should be free from any disagreeable odour. When held flat on hand by head, the tail should not droop. It should not feel soft or leave an impression or depressed mark when pressed by a finger. Its skin should be intact and scales should not be easily detachable. If not eviscerated a sound dead fish sinks in water.

A decaying fish has dull grey sunken eyes, grey muddy gills, the scales become detached and have a characteristic putrefying smell. It may cause ptomaine poisoning. It floats in water with belly up, A putrefying fish shows dark blood or dark tarry liquid on cutting and its body becomes flaccid. A large tapeworm called Dibothriocephaluslatus is conveyed to man by eating insufficiently cooked fish. Fish poisoning may occur due to toxins produced by Cl. botulinus. Its decomposition may give rise to ptomaine poisoning. It may be found that some per­sons possess idiosyncracies especially to muscles, which are said to cause poisoning by mytilo toxin. The chief symptoms produced are dyspepsia, urticaria, swelling of tongue, numbness of limbs, weak irregular pulse etc.

Tinned Meat and Fish.

They are commonly used. It is very essential to see that meat and fish in tins are wholesome, not old and putrefied. The tins should be carefully examined before consumption in the following ways:

On Inspection. There should be no indentations, holes, soldering defects or signs of gross ill usage. It should not be rusty. It should have concave ends and not be bulging or blowing out indicating putrefaction and formation of hydrogen gas in acidic medium. A collapsed tin signifies too much vacuum. All leaking and non-airtight tins should be discarded.

On Palpation. If putrefaction has set in and gas has formed it gives a springy feel with a sense of resistance. It so happens particularly, when air has entered into the tin through a leaking hole and the vacuum is lost.

On Percussion. If the note is tympanitic, it indicates unsound tin due to formation of gas, while a dull note indicates a sound tin.

On Shaking. A sound tin will produce no sound, but if the contents are putrefied and are partially liquid then a loose sloppy sound will be detected.

 

Eggs

 

An average hen's egg weighs about 60 gms, with 2/3rd as white and 1/3 as yolk. It has all the important nutrients except carbohydrates. The egg white is mostly egg albumin; while the yolk contains fat, lecithin, phosphorus, calcium and iron. The egg can be preserved by making their shells air tight by immersing them in lime-water or by coating them with oil or sodium silicate a process of glazing. The test for freshness of an egg: put it in 10% common salt solution; good eggs sink while stale ones will float.

It is a food containing all the proximate principles of food, except carbohydrates necessary for the growth and development of the body. It is a protective food containing first-class proteins with all the essential amino acids and have the highest nutritive value among dietary proteins. In view of the presence of sulphur in the white of egg, they are considered as acid forming foods and resemble meat in this respect.

It consists of an outer shell with its interior white and yolk. The shell consists of carbonate of lime, the white is made up wholly of proteins, the chief being egg albumen and the yolk contains less proteins and a large amount of fat. Besides, it contains lecithin, vitalin and the organic compounds of phosphorus, lime, and iron. It is rich in calcium salts, anti- neuritic and anit-rachatic vitamins.

Yolk of egg is a valubale food for anaemic patients, since it contains iron which is very easily digested and assimilated in the body. Since the fat present in the yolk of eggs is in emulsified form, just like milk, it is easily digested and is almost completely absorbed in the intestines; only 3 % of residue is left.

 

Freshness of eggs can be tested

 

(1)              by holding them in the hand in front of a candle in the dark. Fresh ones being more transparent in the centre and stale ones are transparent at their extremities. This process of testing the eggs is known as Candling.

(2)            By putting them in 10 % salt solution; fresh eggs will sink, whereas stale ones will float.

 

Milk

 

It is an ideal food containing nearly all the nutrients of well balanced diet. It is the best particularly for infants, children, and lactating mothers. It contains milk sugar (Lactose), proteins, fat, vitamins, clacium pJzosphorus, chloride, potassium and sodium but is poor in iron.

It is a food material of special importance. It is almost complete, an ideal food and contains most of the proximate principles of a well balanced diet required for human body. It is thus the nearest approach to perfect food. It forms the only diet of children to the age of a year or so. It is the best source of calcium in diet both on account of quality and the valuable assimilable form in which it exists. It provides proteins of high biological value to the body.

Milk contains the following proximate principles:

1. Proteins: 3,5% of total weight, consisting of 3 % Caseinogen, 0,4 % Lact albumen, and 0,1% Lacto-globulin. Milk proteins are of high biological value. Cow's milk is rich in casein, and human milk in Lactalbumi

2. Carbohydrates: The carbohydrate in all milks is lactose or milk sugar (4 to 5%). Human milk contains more lactose than cow's milk

3. Fats:  3,5 to 4 % in the form of glycerides in emulsified form. Milk fat is a good source of vitamins A and D When milk is allowed to stand for sometime, fat rises to the surface as cream. Chemically milk fat consists of myristin, olein, palmitin and stearin.

4. Vitamins: It contains all the vitamins except vitamin E. In summer, cows, if fed on grass, produce milk containing large amount of vitamins B, C and D. But in winter, amount of vitamins A and D in milk is much reduced.

5. Mineral Salts: Phosphates and chlorides of calcium, potassium and sodium. It is poor in iron.

Methods of Preservation of Milk

These are as follows:

(1) Boiling is ancient method of rendering the milk safe for human consumption.

(2) Pasteurisation. According to WHO, pasteurisation may be defined as the heating of milk to such temperatures and for such periods of time, as are required to destroy any pathogenic organisms that may be present, while causing minimal changes in the composition, flavour and nutritive value of milk.

There are various methods of pasteurisation of milk. Some of them are as follows:

Ø               Holder or Vat Method. In this method milk is heated and kept at 63 to 66°C for 30 minutes and then quickly cooled to below 5 °C.

Ø               High Temperature and Short Time method: milk is heated rapidly to a temperature of 72 °C and then quickly cooled to below 5 °C.

Ø               Ultra High Temperature method: The temperature of milk is raised to 125 to 150 °C for a few seconds only and then rapidly cooled

3. Sterilisation. This is done by raising the temperature to 100°C and then by maintaining it for 15 minutes in closed sterilised vessels. It kills all micro-organisms and their spores. The disadvantages is that vitamin C and B are destroyed to one-half and one-third respectively of their original content. The biological value of proteins is said to be slightly reduced. It is unsuitable for feeding infants.

4. Drying or Desiccation The milk prepared from this powder is of uniform composition, free from all dangerous organisms and easily digested by infants, as the curd formed in their stomach is more flocculent and finely divided than that of the fresh cow's milk. The vitamin content of dried milk is variable. Vitamin C is reduced considerably. So when it is given to infants, orange juice or any other vitaminised preparation should be added to it.

 

 

Cream. It is prepared by allowing the milk to stand for a considerable time in the cold so that butter fat may rise to the top and then removing the top layer. The fat or cream may be separated from milk mechanically through a centrifuge machine known as a separator or it may be obtained by churn­ing the curdled milk. Cream may contain about 50 % fat. Besides milk fat, cream contains proteins and lactose also.

Butter: It is the most nutritious and easily digestible form of all fats. Good butter should neither be rancid nor have an unpleasant odour. Specific gravity of butter fat varies from 0.911 to 0.913. Its melting point is 35.8°C.

Its average composition should be:

Water              12 - 15 %

Fat         80 - 90 %

Caseinogen     1 - 3 %

Lactose                 1%

Ash                     2-3%

Salt and Vitamins -q.s.

Cheese

 

It is a very concentrated protein food and methods of making it vary considerably at different places. It is prepared by coagulating caseinogen of whole milk or skimmed milk with rennet. Cheeses differ by high content of  protein (20-25 %), fat (25-30 %) and what is also important – calcium and phosphor.

Vegetable Foods

These are cereals, pulses, roots, green vegetables, fruits and nuts.

Cereals are mainly carbohydrates and also contain minerals (P, Cal, Mg, K, Fe). Wheat and rice are the main cereals. A good wheat flour must have at least 8% gluten. Usually it has 60-70% car­bohydrates and 10-12% gluten.

Rice is poor in proteins, fat and minerals, but very rich in starch.

Barley is rich in proteins and minerals.

Maize is rich in proteins, carbohydrates and fatty matter.

Oat is rich in protein and carbohydrates.

Bajra is rich in protein and carbohydrates.

Pulses are nitrogenous substances. Vegetable protein is legumin (24-25%). Minerals are potassium, calcium and sulphur. Pulses also contain carbohydrates but are deficient in fats.

Roots and tubers ^.potatoes, beet-roots, carrots etc,

Vegetables arc usually a rich source of minerals and vitamins.

Fruits: These may be food fruits or fruits of flavour fruits.

Flavour fruits e.g., orange, lemon. These quench thirst and are rich in Vit C and minerals.

Nuts like ground nut are very rich in proteins.

In general, vegetable foods form more bulk and have less protein. If proportion of vegetable in food is very high, the bowels get dis­tended and there is more muscular effort on intestine and more blood and energy required for the purpose.

Beverages and condiments are substances which enable food to be taken with pleasure and relish and aid digestion. These are water (universal beverage) tea/ coffee, fermented drinks, spices, etc.

Wheat

         It is the most important of all cereals and is extensively used all over the world. It contains 60-70 % starch, 8-12 % gluten and 15 % water. The seeds have an outer envelope called pericarp, which is very hard. It is composed mainly of cellulose and mineral matter and forms about 13 % of the grain. A middle layer called endosperm or kernel consists chiefly of starch. It forms 85 % of the grain. The germ or embryo forms about 1.5 % of the entire grain. It is rich in protein and fat.

 Flour is prepared by grinding up wheat.

             

 

Rice

 

 

    In fact, it forms the staple article of diet for half the population of the world. In composition, it is poorest in proteins, fats and mineral matter, out of all the cereals and has no cellulose contents or roughage. Its chief constituent is starch, which is in a very digestible form. It is digested within 3-4 hours. Being rich in starch it is eaten with nitrogenous and fatty substances, like pulses, fish, ghee etc., to supply the deficiency in proteins and fats. The bulkiness of rice eaters' diet gives rise to two important consequences:

(i) it tends to prevent the absorption from the intestines of the proteins and vitamins contained in other foods eaten with it, as dais or pulses

 (ii) it is apt to cause disten­sion of the stomach and bowels with fermentation of their contents, thus result in indigestion and bowel complaints.

The outer layer or pericarp contains vitamin B1 and its complete removal may give rise to beri-beri in rice eating population. Rice does not contain vitamins A, C and D.

 

Barley

 It is very nutritious and is characterized by its richness in mineral salts and fat but is poor in gluten, so it is unsuited for making bread.

 

Maize

It is as nutritious as wheat, and richer in fats than all cereals except oats. It contains 10 % proteins, 65 % carbohydrates, 5 % fats, 1-2 % salts and 14 % water. Maize is poor in certain amino acids—such as tryptophane. It is deficient in vitamins, the anti-scorbic and anti-pellagra factors being absent and an exclusive use of maize may cause pellagra.

 

Oats or Jao.

These are highly nutritious. They are deficient in vitamins A and D and gluten. Oats are used as oatmeal porridge and should be eaten with plenty of milk.

 

Fruits

                 Fruits contain a large amount of sugar, vegetable acids and salts. These are protective foods. According to their nutritive value fruits have been divided into food fruits and flavouring fruits.

                 Food fruits are those which afford nutriment, and include bananas, dates, figs, grapes, mangoes etc. Their nutritive value depends on the presence of carbohydrates, which exist in the form of sugar and commonly known as levulose or fruit sugar. Certain fruits such as lemons and oranges are rich in potassium salts, lime and magnesia and contain vitamin C.

The fruits are valuable because:

Ø     They have cooling effect and quench thirst.

Ø     They contain important mineral salts of potash combined with vegetable salts.

Ø     They have anti-scorbutic properties being the richest sources of vitamin C and for this reason they are included in children's dietary. They prevent scurvy.

Ø     They prevent constipation.

Nuts.

                 They differ from fruits as they have higher calorific and nutritive value, being rich in proteins and fats. The common nuts are almonds, cocoa nuts, ground nuts, walnuts etc. They are rich in vitamin B but contain very little vitamin A and no vitamin C.

 

 

Metabolism

It is process of chemical changes occurring in the body after diges­tion and absorption of food nutrients, their utilisation by body tissue, for processes of synthesis (anabolism) and for those of breakdown (catabolism).

Energy for basal metabolism: This is the energy necessary for maintaining body temperature and for activity of heart and vital organs, when body is at complete rest The basal metabolic rate (BMR) of an average adult is 1500-1700 Cal/day and is dependent on body weight, age, sex, state of health, mental state and the environments.

Food Calorie

A calorie is defined as the amount of heat required to raise the temperature of 1 gm of water through 1°C from 14.5°C to 15.5°C.

Unit of Food (Cal.) 1 - 1,000 small calories.

 1 gm. of carbohydrate produces    4.1 Cal.

 1 gm. of fat produces             9.3 Cal.

 1 gm. of protein produces          4.1 Cal.

Family co-efficient: It is relative energy requirement of various members of household in terms of such units expressed as mean value taken as one:

So for adult male unit is            1

For adult female unit is          0.9

For pregnant women unit is      1.2

For nursing mother unit is        1.5

BALANCED DIET

Balanced diet is one, which will meet a person's caloric need and contain all nutrients, particularly proteins, and vitamins. In addition, the food should satisfy the taste and desire of a person and should have enough roughage to promote the peristalsis. Balanced diet should have 50-60% carbohydrates 30-35% fats and 10-15% proteins with necessary vitamins and minerals.

Methods of sampling and organoleptic research of the food products and ready meals

 

The hygienic examination of food products and ready meals is made in following situations:

- regularly, by the plan;

- sporadically during raid control of nutrition units, catering objects;

- urgently if the cases of food poisonings, alimentary caused diseases, severe violations of nutrition units sanitary regimen (canteens, cafes, restaurants, hospital nutrition unit and etc.) are registered;

The hygienic examination of food products may have the following purposes:

- determination of products commercial qualities, drawing up of certificates;

- detection of the falsification, imbalance of the products’ chemical composition;

-  to control the realization terms of products;

- determination of the degree of product deterioration during storage and possibility for further storage;

- determination of epidemiological and toxicological danger of products (microbial contamination, pollution by pesticides and other toxicants, barn parasites, mold etc.);

- determination of harmfulness of package, crockery, equipment, inventory and others.

Methods of sampling for laboratory analyses depend on the type of products, (free-flowing, by the pieces, liquid, in or without the package and etc.). The average sample representing the quality of all food lot has to be selected.

The free-flowing and solid food products (cereals, grain, flour, solid fats etc.) are selected with special probes, knives (see fig. 1), scoops from different sites of package or food cargo (up to 10 examples from which the average sample with mass up to 1 kg is formed).

Fig. 1 Cylindrical Zhuravlova’s knife for bread sampling

 

At first the liquid and soft food products are mixed (by twirling stick and shake), selected from the different packages, product cargos and the average sample is received.

Closed preserved products are selected from the cargo by the piece, in the first place – the suspected units (blown cans, with damaged package).

The meat is sampled by cutting from the carcass, semi-carcass with obligatory sampling of the bones, joints.

Free-flowing, solid products without package and by the pieces are selected into plastic sacks, liquid – into glass package. The samples obligatory are sealed. The act of sampling is drawn up and signed by the person who performs the sampling and the responsible person of the nutrition unit. The accompanying form is enclosed in the sample. The following data are contained in this form: the nutrition unit ratings, specimen sample mass or quantity, laboratory research purpose, laboratory address where the samples are headed for, date and time of sampling, signature of the person who performed the sampling.

The organoleptic research of food products (and ready meals) does not need special equipment, may be performed both in the laboratory and at the nutrition unit during sampling.

At first it is necessary to get acquainted with the nutrition unit’s documentation, bills, certificates for the product cargo, delivery date. Then the storage conditions, products processing, presence of refrigerators, object sanitary condition, conditions of packages, marking (terms of product sale and storage etc.) are examined.

The appearance of product samples (in daylight), their color, tints as the signs of staleness, spoiling or falsification, suspected impregnation, spots, different from the color of the product etc. are also examined. The presence of barn parasites, cysticercuses is determined with the loupe and trichina grubs – with compressorius. (see fig. 2, 3, 4, 5)

Fig. 2 Barn parasites and their grubs

(1 – big floury beetle; 2 – Suriman flour eater; 3 – little flour beetle; 4 – barn weevil; 5 – rice weevil; 6 – pea weevil; 7 – red flour eater; 8 – weevil-pickleworm; 9 – flour pickleworm; 10 – pretenter evildoer; 11 – grain moth; 12 – mill pickleworm ; 13 – flour ticks)

 

Fig. 3 The meat affected with cysticercuses (beef or pork tapeworm embryos)

 

Fig. 4 Trichina grubs in the pork

 

 

Fig. 5 Compressorium for determination of the trichina grubs in the pork

 

The constitution is determined by palpation – pressing on the product (bread-crumb, meat). The pit smoothens if the product is fresh or stays if the product is stale.

If the food products are fresh their smell is pleasing, specific. The stale products have objectionable even putrefactive smell. Some fresh products have to be odor-free at all.

The taste is tested the last after making sure that the product is safe. The taste is not tested if the product is suspected of spoiling or contamination with microorganisms, toxic agents.

Sometimes the hearing may also be used (splashing in the cans if they are filled incompletely, no fizzing in carbonated beverages, fizzing during fermentation etc.).

The boiling test of broths from research products first of all from meat is used in the laboratory during the organoleptic research.

 

The laboratory research of caloricity, commercial qualities and food product freshness

 

The following criteria among the integral food quality criteria are determined:

- moisture after drying of the previously weighed sample or distillation of it to permanent mass; the moisture of liquid products is determined using areometer, lactometer (milk) (see fig. 6, а).

- solid residue is also determined after drying, determination of the density with aerometer or calculation by moisture.

- ash residue is determined by burning the solid residue to light-grey ash of mineral substances.

The protein content in the food product or ready meal is determined as content of the total nitrogen in the product. The total nitrogen is determined according to the Kieldall’s or Lourie’s method (stated in the special manuals). The protein content is determined by multiplication of the nitrogen quantity by the coefficient of 6,25.

The fat content in products is determined according to the classical Soxlet methods after extraction of the fat from the product using ether into the Soxlet device. The other methods of determination the fat content in products are also stated in special method, educational manuals, in milk – using the butyrometer (see fig. 6, b).

The carbohydrate content in food products (mono-, di-, polysaccharides) is determined using the iodometric methods, by their inversion, hydrolyses. The details of these methods are also described in special manuals.

The vitamin content (at the first place - the ascorbic acid, carotene) is determined in most cases during laboratory analyses of the vegetable cans, milk, ready meals.

The mineral salts and microelements are usually determined in special purposes (scientific purpose etc.).

 

            

Fig. 6 The lactometer (a) – device for determination of measuring the milk density, butyrometer (b) – device for the fat content determination in milk

Butyrometer

Butyrometer widely used for rapid determination of FAT content in Milk and milk products.

Lactometers

 

Lactometers which are an instrument extensively used for the testing of richness of the milk.

Specific criteria of quality, freshness, epidemiological, toxicological infectiousness of food products are determined for different products (see appendix 3) and by recommendation.

The food products chemical composition is stated in tables of appendix 3 of the lesson “Method of assessment of nutrition adequacy in organized collectives using the menu schedule”. These tables are also used during the expert assessment of the laboratory analyses results.

http://www.fao.org/docrep/011/t1265e/t1265e04.htm#TopOfPage

 

 

State standards and hygienic regulations of main food products

 

1.           Quality criteria of milk (State standard of Ukraine 3662-97)

 

2.           Standard requirements to bread, macaroni

 

3.           Quality criteria of grains

 

 

4. Quality criteria of meat, fish

       The quality and freshness criteria of other products are stated in corresponding manuals, text-books (see recommended literature).

Different Vitamins play different role in our body.

Some vitamins act in groups with each other whereas others act alone. Functions of different vitamins are given below:

Vitamin A helps in regeneration of visual purple, prevents night blindness and helps to maintain good eyesight. It also prevents the condition known as urolithiasis where urinary calculi in the form of calcium phosphate are present. It is also essential for growth. 

Vitamin D is essential for bone development and also prevents rickets. Vitamin D maintains normal structure of bone and helps to maintain the equilibrium between bone calcium and blood calcium. It also helps in the normal development of teeth.

Vitamin E prevents sterility and muscular dystrophy.

Vitamin K is essential for the formation of prothrombin of blood, hence essential for blood clotting and prevents haemorrhage or excessive loss of blood from the body during injury or accidents. The haemorrhagic disease in the newborn is believed to be due to lack of vitamin K, since vitamin K deficiency in the newborn is due to absence of bacteria in their gut.

Vitamin B1 prevents the disease known as Beri beri. It has a potential role in the oxidation of sugar in tissues, including brain. In its absence, pyruvic and lactic acid fails to be metabolized with a result of accumulation of these substances in blood and tissues. It also helps the enzyme system, which is responsible for the synthesis of fats from carbohydrates and proteins.

Vitamin B2 is concerned with oxidative processes in the cells. It acts as a coenzyme for flavoprotein enzymes in the body. Deficiency produces loss of appetite and weight. Therefore it is essential for growth.

Nicotinic acid prevents the disease known as pellagra. It helps in the formation of fats and carbohydrates. It is also essential for growth.

Vitamin B6 prevents skin diseases, especially itching and redness of the skin. It is also related to the metabolism of unsaturated fatty acids and also helps in the synthesis of fats from carbohydrates. This vitamin with the help of thiamine increases the formation of fats from proteins.

 Folic acid prevents macrocytic anemia in human being. It takes part in the formation and maturation of the red cells. It is also required to maintain the normal pregnancy.

 

Vitamin B12 prevents pernicious anaemia. Essential for the formation and maturation of red blood cells. It also increases the white cell count and the platelets through its action in the bone marrow. It is also concerned with the normal health and activity of certain parts of the nervous system. This vitamin is also essential in the biochemical conversion of carbohydrate to fat or fat to carbohydrate.

   Vitamin H deficiency in man causes peculiar dermatitis. Absence of this vitamin produces lassitude and sometimes gastro-intestinal symptoms.

   Para-amino-benzoic amino acid (PABA) prevents premature graying of hair in rats. Its role in human nutrition is not definitely established.

   Vitamin B4 and B5 are essential for the growth of pigeons. Their value in human dietary is not yet proved.

  Vitamin C prevents human scurvy. It is also involved in many other important physiological functions. It is essential for the proper functioning of the formative cells of various tissues, such as fibroblasts, osteoblast etc. it plays an important role in wound repair. The synthesis of insulin in the beta cells of islets of Langerhans is impaired during vitamin C deficiency, resulting in hyperglycemia and disturbance in carbohydrate metabolism.

 Vitamin P acts as a permeability factor. It is closely related to vitamin C and helps its action.

Vitamin B3 takes part in carbohydrate metabolism. The condition of alopecia (falling of hair) and certain gastro- intestinal disorders are produced by the deficiency of this vitamin. Vitamin B3 in the form of CoA takes part in the reaction of both the synthesis and metabolism of fatty acids and cholesterol.

A variety of potent and essential antioxidants, that defend the body against the dangers of free radicals, should be included in any vitamin or multivitamin. Among the most popular antioxidants are: coenzyme Q 10, which is vital for heart and liver health, as well as for the production of cellular energy; selenium for immune functioning and possibly a reduction in certain degenerative diseases, such as cancer; and lutein, which has been shown to offer unbelievable visual benefits.

 

Nutritional Diseases:

Important nutritional diseases are listed as hereunder:

1. Protein Calorie Malnutrition (PCM).

(i) Kwashiorkor. It results from consumption of very low protein in diets of low biological values, yet providing just enough energy to satisfy the needs of the child. This condition is usually seen in children between the age group of 1-4 years. This symptom is characterised by pitting oedema, anaemia, retarded growth, loss of appetite, diarrhoea, scanty hair growth...

 

(ii) Marasmus. It is a clinical condition of protein energy malnutrition, primarily due to totardeprivation of the requisite calories required by the body. It usually occurs in the age group of 1/2 to 5 years. This syndrome is characterised by failure to gain weight, wasting of muscles and of subcutaneous fat. The child feels good appetite but is irritable.

(ii) Marasmic-Kwashiorkor. Patients suffering from Marasmic-Kwashiorkor show clinical symptoms of both Marasmus and Kwashiorkor.

2. Protein Deficiency in Adults. Protein deficiency in adults is also quite prevalent in poverty areas. Protein  deficiency  will  result  in  adults  having reduced weight, reduced subcutaneous fat, anaemia, greater susceptibility to infection, frequent loose motions, general lethargy, delay in healing of wounds and oedema.

3. Mineral Deficiencies

(i) Deficiency of iodine in water and feed leads to goitre,

(ii) Lack of flourine ( < 0.5 ppm) in water leads to caries

(iii) Calcium deficient diets lead to rickets and osteomalacia

(iv) Iron deficiency diets lead to anaemia,

(v) There are other important minerals like copper, selenium etc.Usually their requirements are so little that deficiency conditions do not occur.

4.     Vitamins Deficiencies,

(i) Lack of vitamin A results in xerophthalmia, Bitot's spots, night blindness and keratomalacia.

(ii) B Complex: Deficiency of Thiamine leads to beri beri. Niacin deficiency results in pellagra.

 

 

Riboflavin deficiency symptoms are angular stomatitis, cheilosis, scrotal dermatitis and   corneal  vascularisation. 

 Other   B   Complex eficiencies also result in glossitis, cheilosis and angular stomatitis,

 

 

 

 

(iii) Vitamin C deficiency leads to scurvy, spongy bleeding gums, haemorrhages in skin and other haemorrhages,

(iv) Vitamin D deficiency result in rickets and osteomalacia.

 (v) Vitamin K deficiency leads to hypoprothrombinaemia, which further leads to haemorrhages.

5.    Problems  of Over-nutrition. 

(i) Obesity: The main features of obesity are overweight and fatness.It is mostly caused by overeating and intake of abun­dance of calories

 (ii) Hypervitaminosis A is at times caused by excess of vitamin A therapy. The manifes­tation are headache, nausea, vomiting, irritability and anorexia. Carotenaemia is also caused due to excessive consumption of carrots which is charac­terised by yellow skin with normal conjunctiva,

 (iii) The toxic manifestations of hypervitaminosis D are anorexia, nausea, vomiting, thirst, polyuria and drowsiness. Calcium and phosphorus levels in serum and urine are raised. Calcium may be deposited in many tissues also,

 (iv) Fluorosis occurs if fluorine is available > 1,5 mg in water. It is characterised by (a) dental fluorosis, i.e., mottled enamel of teeth and (v) skeletal fluorosis i.e., dense bone formation, severe spondylitis and even calcifications of ligaments of spine and tendinous inflamation of other muscles in severe cases.

BASES OF TREATMENT - PROPHYLACTIC NUTRITION

Treatment-prophylactic nutrition – is a special nutrition for workers of harmful enterprises. The base of this nutrition is rational nutrition, which is structured according to metabolism of harmful substances in the human organism and curative action of some nutrients, which protect human organism from negative influence of chemical compounds and physical factors. Treatment-prophylactic nutrition is an obligate component of protective health-proving measures, directed on limitation of negative action of harmful factors on production on the organism.

Treatment-prophylactic treatment is directed on:

v    elimination of possibility of harmful substances    penetration into internal medium of the organism from the digestive tract, meaning their binding in stomach and intestines;

v    quickening of excretion of harmful substances from the human organism;

v    increasing of general resistance of the organism towards harmful factors;

v    protection of certain, most damageable systems of the organism from harmful action of toxic substances;

v    quickening or on the opposite slowing down toxic substances metabolism in the organism (aiming to stop their income into internal medium).

In Ukraine there are 3 kinds of treatment-prophylactic nutrition on harmful enterprises:

Ø     Treatment-prophylactic ratios.

Ø     Milk.

Ø     Synthetic vitamin drugs.

Introduction of treatment-prophylactic nutrition as a rule follows after theoretical and medical-biological investigations directed on determination of mechanism of action of certain harmful substances and their combinations on the organism.

       Complex interrelations between components of the mixture are determined during studying of complex action of several toxic substances; as if they enter the organism together character of their toxic action may change (synergism or antagonism). After detoxic action of different nutritive products and substances is studied. It is proved that many nutrients have a considerable detoxicating action. Thus, pectin substances are able to bind heavy metals and radionuclide in digestive tract, preventing their absorption and entering internal medium of the organism. Sulfur containing amine acids methyonin, cystin, magnesium salts promote excretion of some toxic substances from the organism. Vitamins raise protective capabilities of the organism.

In case of constant poisonings with chemical substances their multiple influences on the organism is often performed, presented by damage of central and peripheral nervous system, internal organs (liver, kidneys, respiratory organs) and blood producing organs (anemia often develops). General result of the influence of all chemical substances on the organism is disordering of functional condition of liver, which leads to its inflammation (hepatitis), and after to cirrhosis.

Following principles are followed during organization of treatment-prophylactic nutrition:

1.                                         As a usual result of influence of all chemical substances on the organism is disordering of liver function, so in treatment-prophylactic nutrition a considerable attention should be paid to nutrients and substances which increase functional condition of liver and limit consumption of substances and products which overload its work. Products, which increase functional condition of liver, are: milk, sour-milk products, cheese and cottage-cheese. Wide usage of milk products in treatment-prophylactic nutrition is explained by considerable contents of sulfur containing amine acids (methyonin, cystin), which protect liver from fat infiltration.

2. Quantity of fats should be limited as they speed up absorption of many chemical substances, most of which are fat-soluble substances.

3. Treatment-prophylactic nutrition should be provided by a necessary quantity of fruit and vegetables, which are the source of many water-soluble vitamins, carotene, microelements, pectin substances and fiber.

4. Treatment-prophylactic nutrition should have an alkali orientation. Disorder of acid-base balance of the organism to acidosis side leads to increasing of harmful substances income into blood, for example, lead, and moving to alkalosis side promotes accumulation of many toxic substances in the organism. Milk, milk products, fruit and vegetables possess alkaline properties.

5. Consumption of salt should be limited, since it promotes water retention in the organism.

6. Treatment-prophylactic nutrition should be provided based on general rational nutrition.

Food-borne Illness

Food-borne illness (often called food poisoning) occurs when you eat food that is contaminated.

Food-borne illness is a general term for:

•         Infections caused by micro-organisms such as bacteria, viruses, and parasites. 

•         Poisoning by toxins from bacteria or mould in food.

•         Poisoning by chemicals in food.

There are currently over two hundred diseases that are transmitted through food (Institute of Food Technologists Expert Report on Food Safety Issues in the 21st Century, 2002).

Hazardous Food

Food, which consists in whole or in part of:

•         Milk or milk products

•         Eggs

•         Meat

•         Poultry

•         Fish

•         Shellfish

Meringue and other desserts containing dairy products are considered hazardous foods.  Hazardous food must be refrigerated.

Fruits and vegetable, which are generally considered low risk foods can still become contaminated through food handling or production processes.  Be sure to follow safe food handling practices and thoroughly wash fresh fruits and vegetables before preparation.

 

FOOD POISONING

Definition

Food poisoning is a general term for health problems arising from eating contaminated food. Food may be contaminated by bacteria, viruses, environmental toxins, or toxins present within the food itself, such as the poisons in some mushrooms or certain seafood. Symptoms of food poisoning usually involve nausea, vomiting and/or diarrhea. Some food-borne toxins can affect the nervous system.

Description

Every year millions of people suffer from bouts of vomiting and diarrhea each year that they blame on "something I ate." These people are generally correct. Each year in the United States, one to two bouts of diarrheal illness occur in every adult. The Centers for Disease Control and Prevention (CDC) estimates that there are from six to 33 million cases of food poisoning in the United States annually. Many cases are mild and pass so rapidly that they are never diagnosed. Occasionally a severe outbreak creates a newsworthy public health hazard.

Classical food poisoning, sometimes incorrectly called ptomaine poisoning, is caused by a variety of different bacteria. The most common are Salmonella, Staphylococcus aureus, Escherichia coli O157:H7 or other E. coli strains,Shigella, and Clostridium botulinum. Each has a slightly different incubation period and duration, but all except C. botulinum cause inflammation of the intestines and diarrhea. Sometimes food poisoning is called bacterial gastroenteritisor infectious diarrhea. Food and water can also be contaminated by viruses (such as the Norwalk agent that causes diarrhea and the viruses of hepatitis A and E), environmental toxins (heavy metals), and poisons produced within the food itself (mushroom poisoning or fish and shellfish poisoning).

Careless food handling during the trip from farm to table creates conditions for the growth of bacteria that make people sick. Vegetables that are eaten raw, such as lettuce, may be contaminated by bacteria in soil, water, and dust during washing and packing. Home canned and commercially canned food may be improperly processed at too low a temperature or for too short a time to kill the bacteria.

Raw meats carry many food-borne bacterial diseases. The United States Food and Drug Administration (FDA) estimates that 60% or more of raw poultry sold at retail carry some diseasecausing bacteria. Other raw meat products and eggs are contaminated to a lesser degree. Thorough cooking kills the bacteria and makes the food harmless. However, properly cooked food can become recontaminated if it comes in contact with plates, cutting boards, countertops, or utensils that were used with raw meat and not cleaned and sanitized.

Cooked foods can also be contaminated after cooking by bacteria carried by food handlers or from bacteria in the environment. It is estimated that 50% of healthy people have the bacteria Staphylococcus aureus in their nasal passages and throat, and on their skin and hair. Rubbing a runny nose, then touching food can introduce the bacteria into cooked food. Bacteria flourish at room temperature, and will rapidly grow into quantities capable of making people sick. To prevent this growth, food must be kept hot or cold, but never just warm.

Although the food supply in the United States is probably the safest in the world, anyone can get food poisoning. Serious outbreaks are rare. When they occur, the very young, the very old, and those with immune system weaknesses have the most severe and life-threatening cases. For example, this group is 20 times more likely to become infected with the Salmonella bacteria than the general population.

Travel outside the United States to countries where less attention is paid to sanitation, water purification, and good food handling practices increases the chances that a person will get food poisoning. People living in institutions such as nursing homes are also more likely to get food poisoning.

Causes and symptoms

The symptoms of food poisoning occur because food-borne bacteria release toxins or poisons as a byproduct of their growth in the body. These toxins (except those from C. botulinum) cause inflammation and swelling of the stomach, small intestine and/or large intestine. The result is abdominal muscle cramping, vomiting, diarrhea, fever, and the chance of dehydration. The severity of symptoms depends on the type of bacteria, the amount consumed, and the individual's general health and sensitivity to the bacterial toxin.

Salmonella

According to a 2001 report from the CDC, Salmonella caused almost 50,000 culture-confirmed cases of food poisoning in the United States annually. However, between two and four million probably occur each year. Salmonella is found in egg yolks from infected chickens, in raw and undercooked poultry and in other meats, dairy products, fish, shrimp, and many more foods. The CDC estimates that one out of every 50 consumers is exposed to a contaminated egg yolk each year. However, thorough cooking kills the bacteria and makes the food harmless. Salmonella is also found in the feces of pet reptiles such as turtles, lizards, and snakes.

About one out of every 1,000 people get food poisoning from Salmonella. Of these, two-thirds are under age 20, with the majority under age nine. Most cases occur in the warm months between July and October.

Symptoms of food poisoning begin eight to 72 hours after eating food contaminated with Salmonella. These include traditional food poisoning symptoms of abdominal pain, diarrhea, vomiting, and fever. The symptoms generally last one to five days. Dehydration can be a complication in severe cases. People generally recover without antibiotic treatment, although they may feel tired for a week after the active symptoms subside.

Staphylococcus aureus

Staphylococcus aureus is found on humans and in the environment in dust, air, and sewage. The bacteria is spread primarily by food handlers using poor sanitary practices. Almost any food can be contaminated, but salad dressings, milk products, cream pastries, and any food kept at room temperature, rather than hot or cold are likely candidates.

It is difficult to estimate the number of cases of food poisoning from Staphylococcus aureus that occur each year, because its symptoms are so similar to those caused by other foodborne bacteria. Many cases are mild and the victim never sees a doctor.

Symptoms appear rapidly, usually one to six hours after the contaminated food is eaten. The acute symptoms of vomiting and severe abdominal cramps without fever usually last only three to six hours and rarely more than 24 hours. Most people recover without medical assistance. Deaths are rare.

Escherichia coli (e. coli)

There are many strains of E. coli, and not all of them are harmful. The strain that causes most severe food poisoning is E. coli O157:H7. Food poisoning by E. coli occurs in three out of every 10,000 people. Foodborne E. coli is found and transmitted mainly in food derived from cows such as raw milk, raw or rare ground beef and fruit or vegetables that are contaminated.

Symptoms of food poisoning from E. coli are slower to appear than those caused by some of the other foodborne bacteria. E. coli produces toxins in the large intestine rather than higher up in the digestive system. This accounts for the delay in symptoms and the fact that vomiting rarely occurs in E. coli food poisoning.

One to three days after eating contaminated food, the victim with E. coli O157:H7 begins to have severe abdominal cramps and watery diarrhea that usually becomes bloody within 24 hours. There is little or no fever, and rarely does the victim vomit. The bloody, watery diarrhea lasts from one to eight days in uncomplicated cases.

Campylobacter jejuni (c. jejuni)

According to the FDA, C. jejuni is the leading cause of bacterial diarrhea in the United States. It is responsible for more cases of bacterial diarrhea than Shigella and Salmonella combined. Anyone can get food poisoning from C. jejuni, but children under five and young adults between the ages of 15 and 29 are more frequently infected.

C. jejuni is carried by healthy cattle, chickens, birds, and flies. It is not carried by healthy people in the United States or Europe. The bacteria is also found ponds and stream water. The ingestion of only a few hundred C. jejuni bacteria can make a person sick.

Symptoms of food poisoning begin two to five days after eating food contaminated with C. jejuni. These symptoms include fever, abdominal pain, nausea, headache, muscle pain, and diarrhea. The diarrhea can be watery or sticky and may contain blood. Symptoms last from seven to 10 days, and relapses occur in about one quarter of people who are infected. Dehydration is a common complication. Other complications such as arthritis-like joint pain and hemolytic-uremic syndrome (HUS) are rare.

Shigella

Shigella is a common cause of diarrhea in travelers to developing countries. It is associated with contaminated food and water, crowded living conditions, and poor sanitation. The bacterial toxins affect the small intestine.

Symptoms of food poisoning by Shigella appear 36-72 hours after eating contaminated food. These symptoms are slightly different from those associated with most foodborne bacteria. In addition to the familiar watery diarrhea, nausea, vomiting, abdominal cramps, chills and fever occur. The diarrhea may be quite severe with cramps progressing to classical dysentery. Up to 40% of children with severe infections show neurological symptoms. These include seizures caused by fever, confusion, headache, lethargy, and a stiff neck that resembles meningitis.

The disease runs its course usually in two to three days but may last longer. Dehydration is a common complication. Most people recover on their own, although they may feel exhausted, but children who are malnourished or have weakened immune systems may die.

Clostridium botulinum (c. botulinum)

C. botulinum, which causes both adult botulism and infant botulism, is unlike any of the other foodborne bacteria. First, C. botulinum is an anaerobic bacterium in that it can only live in the absence of oxygen. Second, the toxins from C. botulinum are neurotoxins. They poison the nervous system, causing paralysis without the vomiting and diarrhea associated with other foodborne illnesses. Third, toxins that cause adult botulism are released when the bacteria grows in an airless environment outside the body. They can be broken down and made harmless by heat. Finally, botulism is much more likely to be fatal even in tiny quantities.

Adult botulism outbreaks are usually associated with home canned food, although occasionally commercially canned or vacuum packed foods are responsible for the disease. C. botulinum grows well in non-acidic, oxygen-free environments. If food is canned at too low heat or for too brief a time, the bacteria is not killed. It reproduces inside the can or jar, releasing its deadly neurotoxin. The toxin can be made harmless by heating the contaminated food to boiling for ten minutes. However, even a very small amount of the C. botulinum toxin can cause serious illness or death.

Symptoms of adult botulism appear about 18-36 hours after the contaminated food is eaten, although there are documented times of onset ranging from four hours to eight days. Initially a person suffering from botulism feels weakness and dizziness followed by double vision. Symptoms progress to difficulty speaking and swallowing. Paralysis moves down the body, and when the respiratory muscles are paralyzed, death results from asphyxiation. People who show any signs of botulism poisoning must receive immediate emergency medical care to increase their chance of survival.

Infant botulism is a form of botulism first recognized in 1976. It differs from food-borne botulism in its causes and symptoms. Infant botulism occurs when a child under the age of one year ingests the spores of C. botulinum. These spores are found in soil, but a more common source of spores is honey.

The C. botulinum spores lodge in the baby's intestinal tract and begin to grow, producing their neurotoxin. Onset of symptoms is gradual. Initially the baby is constipated. This is followed by poor feeding, lethargy, weakness, drooling, and a distinctive wailing cry. Eventually, the baby loses the ability to control its head muscles. From there the paralysis progresses to the rest of the body.

Diagnosis

One important aspect of diagnosing food poisoning is for doctors to determine if a number of people have eaten the same food and show the same symptoms of illness. When this happens, food poisoning is strongly suspected. The diagnosis is confirmed when the suspected bacteria is found in a stool culture or a fecal smear from the person. Other laboratory tests are used to isolate bacteria from a sample of the contaminated food. Botulism is usually diagnosed from its distinctive neurological symptoms, since rapid treatment is essential. Many cases of food poisoning go undiagnosed, since a definite diagnosis is not necessary to effectively treat the symptoms. Because it takes time for symptoms to develop, it is not necessarily the most recent food one has eaten that is the cause of the symptoms.

Treatment

Treatment of food poisoning, except that caused by C. botulinum, focuses on preventing dehydration by replacing fluids and electrolytes lost through vomiting and diarrhea. Electrolytes are salts and minerals that form electrically charges particles (ions) in body fluids. Electrolytes are important because they control body fluid balance and are important for all major body reactions. Pharmacists can recommend effective, pleasant-tasting, electrolytically balanced replacement fluids that are available without a prescription. When more fluids are being lost than can be consumed, dehydration may occur. Dehydration more likely to happen in the very young, the elderly, and people who are takingdiuretics. To prevent dehydration, a doctor may give fluids intravenously.

In very serious cases of food poisoning, medications may be given to stop abdominal cramping and vomiting. Anti-diarrheal medications are not usually given. Stopping the diarrhea keeps the toxins in the body longer and may prolong the infection.

People with food poisoning should modify their diet. During period of active vomiting and diarrhea they should not try to eat and should drink only clear liquids frequently but in small quantities. Once active symptoms stop, they should eat bland, soft, easy to digest foods for two to three days. One example is the BRAT diet of bananas, rice, applesauce, and toast, all of which are easy to digest. Milk products, spicy food, alcohol and fresh fruit should be avoided for a few days, although babies should continue to breastfeed. These modifications are often all the treatment that is necessary.

Severe bacterial food poisonings are sometimes treated with antibiotics. Trimethoprim and sulfamethoxazole (Septra, Bactrim), ampicillin (Amcill, Polycill) or ciprofloxacin (Ciloxan, Cipro) are most frequently used.

Botulism is treated in a different way from other bacterial food poisonings. Botulism antitoxin is given to adults, but not infants, if it can be administered within 72 hours after symptoms are first observed. If given later, it provides no benefit.

Both infants and adults require hospitalization, often in the intensive care unit. If the ability to breathe is impaired, patients are put on a mechanical ventilator to assist their breathing and are fed intravenously until the paralysis passes.

Alternative treatment

Alternative practitioners offer the same advice as traditional practitioners concerning diet modification. In addition they recommend taking charcoal tablets, Lactobacillus acidophilus, Lactobacillus bulgaricus, and citrus seed extract. An electrolyte replacement fluid can be made at home by adding one teaspoon of salt and four teaspoons of sugar to one quart of water. For food poisoning other than botulism, two homeopathic remedies, either Arsenicum album or Nux vomica, are strongly recommended.

Prognosis

Most cases of food poisoning (except botulism) clear up on their own within one week without medical assistance. The ill person may continue feel tired for a few days after active symptoms stop. So long as the ill person does not become dehydrated, there are few complications. Deaths are rare and usually occur in the very young, the very old and people whose immune systems are already weakened.

Complications of Salmonella food poisoning include arthritis-like symptoms that occur three to four weeks after infection. Although deaths from Salmonella are rare, they do occur. Most deaths caused by Salmonella food poisoning have occurred in elderly people in nursing homes.

Adults usually recover without medical intervention, but many children need to be hospitalized as the result of E. coli food poisoning. E. coli toxins may be absorbed into the blood stream where they destroy red blood cells and platelets. Platelets are important in blood clotting. About 5% of victims develop hemolytic-uremic syndrome which results in sudden kidney failure and makes dialysis necessary. (Dialysis is a medical procedure used to filter the body's waste product when the kidneys have failed).

Botulism is the deadliest of the bacterial foodborne illnesses. With prompt medical care, the death rate is less than 10%.

Prevention

Food poisoning is almost entirely preventable by practicing good sanitation and good food handling techniques. These include:

                keep hot foods hot and cold foods cold

                cook meat to the recommended internal temperature, use a meat thermometer to check and cook eggs until they are no longer runny

                refrigerate leftovers promptly, do not let food stand at room temperature

                avoid contaminating surfaces and other foods with the juices of uncooked meats

                wash fruits and vegetables before using

                purchase pasteurized dairy products and fruit juices

                throw away bulging or leaking cans or any food that smells spoiled

                wash hands well before and during food preparation and after using the bathroom

                sanitize food preparation surfaces regularly

Food poisoning

 

 

The prophylactic measures of food poisonings

 

         1. Organization and the compliance to the sanitary regulations of the food products storage by their producers, their processing at the food enterprises and other public catering establishments.

         2. The compliance to sanitary regulations during the food products loading, transportation, storage at the warehouses and trading network, rodents and harmful insects control, refrigerating plant uninterrupted usage.

         3. The compliance to sanitary regulations during the food processing, ready meal storage and sale.

         4. Keeping the technical equipment, kitchens, crockery (plates and dishes), inventory in the proper order.

         5. The regular sanitary inspection of eating establishments; the regular inspection of animal husbandry and meat supply networks by the veterinary service.

6. The medical examinations and inspections for bacilli and helminthes carriers among the personnel of catering establishments (industrial, storage, nutrition units, trading network etc.), the inspection for keeping of the personal hygiene regulations etc. by the personnel.

 

REFERENCES:

Principal:

1.          Hygiene and human ecology. Manual for the students of higher medical institutions/ Under the general editorship of V.G. Bardov. – K., 2009. – PP. 14-34, 71-106.

2.          Datsenko I.I., Gabovich R.D .Preventive medicine. - K.: Health, 2004, pp. 14-74.

3.          Lecture on hygiene.

Additional:

1.          Kozak D.V., Sopel O.N., Lototska O.V. General Hygiene and Ecology. – Ternopil: TSMU, 2008. – 248 p.

2.          Dacenko I.I., Denisuk O.B., Doloshickiy S.L. General hygiene: Manual for practical studies. -Lviv: Svit, 2001. - P. 6-23.

3.          A hand book of Preventive and Social Medicine. – Yash Pal Bedi / Sixteenth Edition, 2003 –  p. 26-36, 92-97.