Bacterial contamination of food

Most of the bacteria are transmitted via food and water as a result of contamination with feces.

The main bacteria that cause food infections via colonization in the intestinal via colonization in the intestinal tract are Salmonella, Listeria monocytogenes, Yersinia enterocolitica and Shigella.

None of the bacteria can multiply in food or water or indeed outside the body of the host in which they developed. If they occur in food or water, one hopes that they will be inactivated or killed before they can infect a consumer or the vehicle.

There are a number of reasons and sources which result in the prevalence of bacterial contamination in food products, such as:
*Premises which are difficult to clean
*Lack of staff discipline
*Incorrect staff and product flow
*Poor air quality
*Incorrect direction of air movement

Food that is cooked and then not contaminated before being served is unlikely to serve as a vehicle for most of the bacteria.

Salmonella is the second most common cause of illness traced to contaminated foods and water. Foods most susceptible to Salmonella contamination are meat, fish, poultry, eggs and dairy products.

Much of the bacterial contamination of foods in restaurants, commissary kitchens and commercial processors are due to the poor personal hygiene of workers. Failure to wash hands after using the bathroom, sneezing and coughing into food, and picking noses and skin blemishes can all transmit pathogenic bacteria to food.
Bacterial contamination of food

Food sources of protein and amino acids

Proteins are made up of long chains of building blocks called amino acids. Human obtain protein from both animal and plant foods.

Foods in meat, poultry, dry peas and beans, eggs, and nuts group and in the milk, yoghurt and cheese group contribute an abundance of high quality protein. The protein of these foods contain ample amounts of all the essential amino acids relative to human bodies’ need for them, and the rest of the diet provides protein-sparing energy and needed vitamins and minerals.

Eggs provide the optimal mixture of essential amino acids among food sources; hence, eggs receive the highest quality rating compared with other foods.

Two others, the vegetable group and the grains group, contribute smaller amounts of protein, but they can add up to significant quantities. These foods tend to lack one or more of the essential amino acids. However, there is an exception – soya beans contain all of them.

Mixtures of plant proteins can serve as a complete and well balanced source of amino acids for meeting human physiological requirements.

However, the combination of right foods is necessary to obtain the necessary levels of both the essential or indispensible amino acids.

Protein content of wheat and flour is considered one of the best single indices of bread making quality.

Protein often occurs in foods in physical or chemical combinations with carbohydrates and lipids.
Food sources of protein and amino acids

Cereal of barley

Native to the Middle East and domesticated in the sixth millennium BC, barley is quite possibly the oldest cultivated cereal in the world.

In the last century barley has been used less for food than has wheat because of lesser palatability, baking quality, and milling characteristics.

Containing less gluten than wheat, barley produces leavened bread that is coarser, darker and denser than wheat bread.

Barley is eaten as popped barley, barley flakes, sprouts, barley starch and sweeteners, barley malt, flour supplements, malted milk, infant food syrups, barley tea or coffee substitute, and rice extender.

In 2006, barley joined oats in an approved health claimed for reducing the risk of cardiovascular disease (FDA 2006).

In barley the major component of the soluble fiber fraction is β-glucan, lowers serum cholesterol is not completely understood and it is generally believed that soluble fibers increase the viscosity in the small intestine leading to increased excretion of bile acids and cholesterol to the large intestines.

A connection with the consumption of barley foods and control of diabetes has resurfaced after being all but ignored for hundreds of years.
Cereal of barley

Carbohydrate

In order to carry out its day to day physiological functions and maintain a constant body temperature (due to invariably in an environment of changing temperatures), the body requires a constant source of energy.

Carbohydrates are an important energy source in the human diet. They generally supply about 45% of the energy requirement in developed countries and up to 85% in developing countries.

Carbohydrate are the cheapest, most efficient and most readily available source of food energy in the world, since they are the main constituents of the foods that are the easiest to produce and that can be obtained throughout the world, namely, grains, legumes and potatoes.

Carbohydrate are the most widely distributed, naturally occurring organic compounds on earth.

Carbohydrates have been considered a fundamental source of nourishment and inexpensive and versatile staple of the diet.

The carbohydrates are a class of chemical compounds that consists of carbon, oxygen and hydrogen. The carbohydrates that are important in nutrition include the sugars, the starches, the dextrin and glycogen.

The functional properties of carbohydrates in food include:

*Nutrition

*flavour and color production

*Sweetening

*Texturing

*Plasticizing action and humectancy

Dietary guidance for consumption of carbohydrates has resemble laboratory analysis of carbohydrates: take way fat and protein and the remainder must to be carbohydrate.

Nutritionist generally accept the fact that humans don’t need more than 10-12% kilocalories from protein, and less than 30% of kilocalories from fat.

Subsequently, intake of carbohydrate should be 55% of kilocalories or more.

Human diets historically have contained 40-80% of their energy as carbohydrate although as income increase, so does the fat content of the diet while carbohydrate content of the diet, especially the starch, decreases.

Starch is the major plant polysaccharide that is readily digested in the intestine and thus serves as a source of carbohydrates.

The major portion of energy requirements of human is met by starch of cereal grains and tubers such as potatoes.

What exactly is a carbohydrate? As the names implies, an empirical formula of CH2O (or CH2O) was often encountered, with molecular formulae of C5H10O5 and C6H12O6 being most common.

It was founded in the nineteenth century that carbohydrates in general have a formula Cn(H2O)n. They were therefore thought to be hydrates of carbon and hence were called ‘carbohydrates’.

The water solubility of these molecules was commensurate with presence of hydroxyl groups and there was always evidence for the carboxyl group of an aldehydes of ketone.

Carbohydrate

Food Science and Society

Food science is an interdisciplinary field that evolved first from chemistry, then microbiology and medicine.

The subject concerned with all aspects of food, beginning with harvesting or slaughtering and ending with its cooking and consumption.

It is also considered one of the agricultural sciences, and usually considered distinct from the field of nutrition.

The origin of food science is unclear but history reports that Egyptians, Greeks, and Romans were able to preserve a variety of foods on vinegar, brine, honey or pitch.

The earliest development of agriculture change nomadic societies to settles ones, because farming is more readily done on cultivated land that is already used as a farm.

Once the idea farming of the same land conceived, permanent shelter became more practical and the forerunners for modern house were built.

The protection of the house important enough to cause farmer to group together and to establish boundaries, the forerunners of modern day towns and cities were form.

Food has a role in social and familial bonding; typically food offered as a symbol of friendship and in modern dinner parties and lunch clubs are a common means of social exchange.

What has the science done to increase population? In the first place, by machinery, fertilizers and improved breeds it has increased the yield per acre and the yield per man hour of labor.

Food science is responding to present day and expected future health and safety trends. The use of sciences such biotechnology, genetic engineering, computer technology, microbiology and chemistry will allow the food scientist to help bring to the marketplace new foods that will meet the needs and desires of the consumer.

Many opportunities exist to study food assistance programs in terms of the nutritional and health impact on participants and how this impact could be improved.

The discovery and utilization of scientific principles in food sciences, culminating in the preparation, packaging and distribution of process food, have provided a supply of safe, wholesome, and nutritious foods unknown before in history.

Food science will have a great impact at the manufacturing product and consumer levels, resulting in more efficient production of foodstuff and effecting improvements in both quality and “freshness.”

Food-derived bioactive peptides offers the possibility to prevent and treat disease via dietary intervention and could be possibly be developed into drugs.

There was a study suggest that dietary intervention with diet high in dairy foods, fruits and vegetables is an effective means of lowering blood pressure and hence prevent cardiovascular diets.

The multifactor nature of food is considered in the production of high quality, safe, nutritious food. Food science has been an integral part of society, The contribution of food scientists to the global world food supply is immense.
Food Science and Society

Food in human diet

Food is the main tool for balancing the hormones and chemicals in the body and brain. Once food is broken down into glucose, amino acids and fatty acids, it travels through the bloodstream and feeds all the areas of the body.

It creates all the chemicals that control every system of the body. Food creates a positive or negative hormonal adjustment that lasts for up to six hours. Each meal readjusts the body chemicals.

The function of food is to keep us alive and healthy. The foods we eat derived from plants and animals. Foods are a complex mixture of many different chemical components. Food is that which nourishes the body.

Whenever certain nutrients are missing from the diet or are in short supply for a long time, bodily functions requiring those nutrients become dysfunctional.

Food components vary with the growth, maturation, harvesting or slaughtering, storage and handling of plant and animal parts used as food.

A balanced diet consists of adequate uncontaminated water, safe protein sources, starches (carbohydrates) fats, vitamins, minerals, and trace minerals.

A balanced diet consists of different types of food items includes a variety of foods.

The major aim is to ensure that all nutrients are supplied.

The principle sources of dietary energy are foods that are high in fats, digestible carbohydrates and protein. Fats which contain about 9 kcal per gram are usually highly digestible and the digestion products are readily absorbed.

The important one is that of palatability; fats make very large contribution to the flavor and appetizing quality of foods. May of the commoner food fats such s those of meat and butter have highly distinctive aromas or flavors.

The problem with the modern food supply is that real food is transformed into processed chemicals, which affect the body’s biochemistry.

Meats are domesticated and filled with hormones, additives and antibiotics.

Grains and vegetables are contaminated with pesticides and sprayed with antibiotics.

For some specific food constituents, such as beta-carotene and some vegetables there is some evidence of carcinogenicity to humans, but this does not affect the evaluations of the overall cancer preventive activity of total fruit or total vegetables.

A healthy diet results largely from habit and circumstance. In the hustle and bustle of modern society, many of people ignore proper nutrition, grabbing fat-rich foods because haven’t much time to sit down to a nutritionally balanced meal.

Current fast pace world places a high premium on saving time, often ignoring the importance of eating and living right.

Everyone needs safe water and food. It is time to learn to make the best food choices to control individual body chemistry.
Food in human diet

The meaning of food ingredient

Food ingredient is an ingredient in food recipe. It is a component part or constituent of any combination or mixture making up a commercial food. In Wikipedia encyclopedia ingredient means something that forms part of a mixture. For example, in cooking, a recipe will specify which ingredients are used to prepare a specific dish.

Today’s consumers require much more information about their health and what they eat since they want to select their food in accordance with a wide number of criteria – origin of ingredients, processing and and preservations and to understand the reason why such and such an ingredient has been added or a particular process used.

Ingredients are substances intentionally added to food products in relatively large quantities to modify the dietary intake of energy or to serve as a substitute or to replace major dietary components, such as fats and sugars.

Many commercial products contain a secret ingredient that is purported to make them better than competing products. In the food industry, an active ingredient is that part of a formulation that yields the effect required by the customer.

The best ingredients is necessary, especially for cooking or food processing, because the techniques are used to focus attention on flavors, colors, textures and aroma.
The meaning of food ingredient

Food Intoxication: Staphylococcal Poisoning

The symptoms of staphylococcal poisoning are nausea, vomiting, abdominal cramps, diarrhea, and prostration. While the symptoms last, suffering may be acute, but this is usually for period of only a few hours.

Intoxication are especially important because the preformed toxin may remain in the food if resistant to inactivation.

Diarrhea is uncommon in staphylococcal intoxication. Food poisoning strains of Staphylococcus aureus produce a heat stable enterotoxin that has a direct effect upon the central nervous system.

Generally, the patient recovers without complications. The incubations period after ingestion or eating food containing the toxin is from 1 to 7 hours, usually 3 tom 6 hrs.

Staphylococcal poisoning is often wrongly called ptomaine poisoning.

Ptomaine poisoning, may be developed from taking into the system food that is in a state of decomposition which produced a bacteria or it may be produced by taking wholesome food into the system in too large quantities.

Staphylococcus aureus
Staphylococcus food poisoning is associated most frequently with coagulase-positive Staphylococcus aureus. It is the same bacterium that causes white-head pimples, infections, boils and carbuncles.

These cells are spherical or ovoid in shape, non motile and in liquid cultures, arrange themselves in grapelike clusters, in small groups, pairs, or in short chains.

They grow best in the presence of air but they will also grow in the absence of air. They will grow in media or in foods that contain as much as 10% salt. When these organisms grow in foods they produce a toxin that can be filtered away from the food and from the bacterial cells.

The toxin is not destroyed by cooking. Heating destroys competing microflora and denatures proteins for use by the staphylococcus. It also provides a favorable temperature, for the staphylococci initiate growth at 45 degree on a cooling food.

Staphylococcus food poisoning is usually associated with meat including beef, chicken, ham and other pork products and turkey.

If food not properly stored before consumption, however, staphylococcus may flourish and produce sufficient exotoxin to cause disease.
Food Intoxication: Staphylococcal Poisoning