FOOD SCIENCE

Cryogenic Freezing of food

2012-05-24T17:51:00.007-07:00

Cryogenics is a term defined as the ‘science of low temperature’ and their effect on the properties of the matter.

The introduction of cryogenic gases in the early 1960’s as an alternative to improve freezing processes in the frozen industry was a major product quality and process improvement.

In food processing, cryogenics implies use of very low temperature materials for chilling and freezing.

This type of refrigeration differs from other procedure because it does not depend on external the low temperature production systems.

Cryogenic freezing with nitrogen is carried out by first passing the food through nitrogen vapor at about -50° C and then freezing the food by spraying the refrigerant directly onto the food.

Fish, meat, poultry, fruit, vegetables and bakery products can all be frozen in this way.

The extremely low temperature characteristics of cryogenic food provide the ultimate in chilling and freezing rates.

The physical properties of the cryogenic gases provided an important tool to help the food industry to improve the plant automation, versatility, efficiency and manufacturing cost.

Cryogenic Freezing of food

Food Allergens

2012-05-22T21:05:00.000-07:00

Food allergens are an exaggerated immune response by certain individuals to proteins or their derivatives that occur naturally in some foods.

It is a major cause of life threatening hypersensitivity reactions.

The food allergy might results from sensitization to ingested food proteins or to aeroallergens though the respiratory route. Several pollen allergens can confer cross-reactivity to homologous proteins in plant foods.

Foods most commonly reported to cause allergic reactions are peanuts, tree nuts, soy, milk, eggs, cereals, fish, crustaceans and sesame.

The reactions happen rapidly, usually within a few minutes of exposure to inhaled substance or eating a food.

Allergic reactions to foods vary greatly: from mild gastrointestinal discomfort to skin rashes and potentially life threatening breathing difficulties such as asthma and anaphylaxis.

Currently, the avoidance of the allergenic food is the only method of preventing further reactions for allergenic patients.

When the term ‘allergy’ was coined, it meant an adverse reaction to any substance that does not bother most people. Then, in the 1920’s it was discovered that type of antibody called IgE was involved in many allergic reactions, especially those to inhalants.

The term food allergy refers specially to the immune mediated adverse reaction. Food allergens can be further divided into IgE and non IgE mediated reactions. Food allergens are therefore the antigenic molecules which induce the immunologic response.
Food Allergens

Unsaturated fatty acid

2012-05-17T00:38:00.002-07:00

Fatty acids differ from one another in two ways; in chain length and in degree of saturation. A chain that posses a point of unsaturation is an unsaturated fatty acid. If there is one point of unsaturation, is a monounsaturated fatty acid.

Monounsaturated fatty acids are mainly incorporated into triacylglycerides but are also found in membrane phospholipids, glycolipids and cholesterol esters.

If there are two or more points of unsaturation, it is polyunsaturated fatty acid.

Food fats with more unsaturated fatty acids typically have lower melting points and are more likely to be liquid at room temperature.

The degree of saturation of the fatty acids in a fat affects the temperature at which the fat melts.

Identical unsaturated fatty acids can have different shapes, the carbon chain of a cis fatty acid is bent, and the chain of a trans fatty acid is straighter. Most naturally occurring unsaturated fatty acid are cis fatty acid.

Because cardiovascular disease is correlated with diets high in saturated fats, a diet of more unsaturated fats may reduced the risk of heart attacks and strokes.

Canola oil is an attractive dietary choice because it has a high ratio of unsaturated fatty acids to saturated fatty acids.

Most vegetable and fish oils are rich in polyunsaturated: some vegetable oils, olive oil and canola oil in particular, are also rich in monounsaturated.

Unsaturated fatty acid

Fermentation

2012-05-16T06:16:00.000-07:00

Fermentation technology is one of the oldest technologies employed in the food processing industry.

The term fermentation is derived from the Latin verb ‘fervere’, to boil, which describes the appearance of the action of yeast on extracts of fruits or malted grain during the production of alcoholic beverages.

In general it can be defined as the process of growing a culture of microorganisms in a nutrient medium at maintained physic-chemical conditions and thereby converting feed into desired end product.

Fermentation involves the breaking down of complex organic substance into smaller ones.

The microbial or animal cell obtains energy through glycolysis, splitting a sugar molecule and removing electrons from the molecules.

Fermented products encompass, but are not limited to wine, beer, vinegar, bread, soy sauce, sauerkraut, kimchi, pickled, olive, different fermented milk products, a large number of cheeses and a variety of sausages.

Many species of microorganisms are used for carrying out the process of fermentation to produce useful products. They include bacteria, fungi, algae and actinomycetes.

Several advantage of fermentation technology included:
*Produces value added and add variety to the human being’s diets.
*Preservation of the food.
*Food quality improvement through flavor development, nutrient enrichments.
*The food more nutritious.
*Detoxifies of foods

Today large numbers of chemicals are produced by fermentation technology with the advent genetic engineering and the developments in computer technology.
Fermentation

Processing of Cocoa Powder

2012-05-14T21:20:00.000-07:00

There are two types of cocoa powder, natural and Dutch processed.

Natural cocoa powder tends to be acidic and in many cases, harsh because inferior quality cocoa beans are often used to produce it.

Dutch-processed cocoa powder has been treated to reduce its alkali.

Adding alkali to natural cocoa powder mellows its flavor and darkens its color.

The process adding alkali to cocoa powder was discovered in the early nineteenth century by Coenraad Van Houten, who was Dutch: that’s the reason this type of coca is known as Dutch processed cocoa powder.

Van Houten patented a press that removed most of the bitter fat which accounts for more than half the weight, from the ground, roasted beans.

Through the use of Van Houten’s invention, two distinct products were produced: a hard cacao cake and cacao butter.
Processing of Cocoa Powder

Process of distillation in flavor industry

2012-05-14T17:44:00.000-07:00

Distillation is a process in which the separation of components in a mixture is achieved due to differences in volatility, that is differences in vapor pressure, of the components in the mixture to be separated.

In flavor industry distillation is frequently utilized for the isolation of flavor compounds, the formation of artifacts during distillation has been a subject of considerable interest.

It is extensively used throughout the flavor industry for:
*the recovery of volatile components from aromatic plants materials by distillation. The distillation process can take many form, Direct steam distillation in a blow over uses a very short condensation column. Condensed product is collected directly.

*Fractionalization of essential oils. The process of reclaimating the aroma of fruit products and specifically fruit juice concentrates by fractional distillation.

*The purification of volatile aromatic chemicals from more or less volatile impurities.

*The recovery of solvents during the process of extraction

*The concentration of natural flavoring materials

*In destructive distillation for the production of pyroligneous acid

*In numerous research and analytical technique

After the separation of extract and extraction material a complete removal of solids and cloudy components has to ensue. This filtration process can be performed with continue or discontinuous filters or by centrifugation with full jackets, reciprocal; pusher or sieve centrifuges.
Process of distillation in flavor industry

What is caffeine?

2012-05-13T19:37:00.000-07:00

Caffeine, nicotine and alcohol have been seen as having a greater effect on human civilization than all other nonmedical psychoactive substances combined.

Caffeine stands out among these three drugs because of its ubiquitous use around the world and because it is a ‘cradle to grave drug’.

In fact, caffeine is woven so intricately into social customs and daily rituals that it is often not perceived as a drug.

Moreover, common foods and other products often contain significant amounts of caffeine, although they may not be labeled as such.

Originally regarded as an oddity then as cure for all sorts of ailments, it soon became popular as a beverage.

As a mild central nervous stimulant, caffeine is commonly taken as an energy and alertness enhancer.

Caffeine is also used to enhance athletic performance because of its ergogenic effects.

In modern medicine caffeine is used as an adjuvant to the analgesic actions of aspirin and paracetamol.

Caffeine was found to have a 40% adjuvant effect compared to the of aspirin for the treatment of throat pain due to tonsillopharyngitis.

Caffeine occurs naturally in a variety of plant based products including coffee, tea, cocoa, kola nuts, guarana and mate.

Caffeine is added to cola and non-cola soft drinks, as well as o other common food item, including gum, mints, water and energy drinks.
What is caffeine?

Destruction of Salmonella by heat

2012-05-13T18:08:00.000-07:00

Heating process are widely used in the food industry to enhance product quality and safety. Destruction of Salmonella by heat, it should be explained that as they are heated and a temperature is reached at which they are destroyed, they are not all destroyed at once.

Large numbers are destroyed when the heat is first applied, but the death rate quickly drops.

For instance , if at 48.9 degree C, 90% of the organisms would be destroyed in a period of 5 minutes, it would take 10 minutes to kill 99% of the organisms, 15 minutes to kill 99.9% of the organisms and so on.

Salmonella is not a spore forming organism. It is not, therefore, a heating resistant organism; pasteurization and equivalent heat treatments will destroy the organism under normal circumstances.

It should be noted that if some of these Salmonella organisms in foods survive whatever heating they receive during coking, and the food is thereafter held at temperatures at which they will grow 6.7-43.3 degree C, especially at room temperature, the organisms may grow again to large numbers.

When heating foods, it is important that all parts of the foods satisfy this temperature time requirements.

Some types of cooking is not sufficient to destroy all Salmonella bacteria that may be present in foods. Examples of cooked foods in which these organisms may survive are scrambled, boiled, or fried eggs, meringue, turkey stiffing , oyster stew, steamed clams, and some meat dishes.

Salmonella are more heat resistant in yolk than in whole egg due to the lower pH an higher total solids content in the yolk.
Destruction of Salmonella by heat

Types of vitamin K

2012-05-11T02:18:00.005-07:00

Vitamin K is needed for γ-carboxylase activity which is essential for the formation of active clotting proteins.

Vitamin K is also required for the synthesis of other proteins found in plasma, bone and kidney. Vitamin K was discovered in 1935 by Henrik Dam as a fat soluble compound that prevented hemorrhagic disease in chicken.

There are two different forms of vitamin K:
*Vitamin K1
*Vitamin K2

Phylloquinone (vitamin K1), is the only form found in plans and is the primary dietary source of vitamin K.

Vitamin K1 is freely available in green vegetables particularly in alfalfa, cereals and animal food. The vitamin also called Mephyton. Thus vitamin K1 is 2 methyl, 3 phytyl-1,4 naphthoquinone.

It is a light yellow oil. This form of vitamin also found in vitamin K supplements and is often given to infants to prevent bleeding.

Menaquinone or vitamin K2, is a product of bacteria metabolism and makes only a minor contribution to vitamin K intake. Its absorption appears t be limited.

Another one is vitamin K3. It is 2-methyl, 1-4 naphthoquinone without any side chain or OH group. Also known as menadione, is synthetic analogue of vitamin K. This form of vitamin is neither found naturally in food nor made by intestinal bacteria but is produced commercially.

Types of vitamin K

Cereal nutrition and diet

2012-05-08T00:03:00.000-07:00

Cereals, the most important plant foods in the human diet are derived from seeds of domesticated members of the Graminease, the grasses.

Long before people learned to cultivate the grasses that are today’s cereal grain, they relied upon such grains as a source of nutrients.

It is thus only natural that breakfast cereals made from the cereal grains through modern processing techniques have become primarily contributors of nutrients to our diets.

Now, cereals remain the staple food in most does and in many parts of rural Africa and Asia provide more than 70% of the energy intake.

The nutrients provided by this first meal of the day include those that are indigenous to the cereal grains as well as some that are added in the manufacture of the cereal.

The nutrient contribution of cereal applies to all age groups. Processed cereals are usually the first solid food fed to infants and the cereal feeding frequently is the first of the day.

Carbohydrate is the main substance in cereals. Cereals have crude fiber and starch,. Though the nutritive value of fiber is not much it performs over other valuable functions which enable the motility of intestine.

No one can doubts on the popularity of breakfast cereals among children; all one has to do is look on store shelves at the large number of breakfast cereals designed to appeal to children.

According to one study, among children aged 5-12, those who ate ready to eat cereal three or more times a week consumed significantly less fat and cholesterol and more fiber, B-vitamins and vitamins A and D than those who ate no ready to eat cereal at breakfast.

Cereal also present an important source of protein. Cereal protein is especially valuable in diets when we consider complementation of amino acids between various plant sources.

The Nutrition Facts panel on a box of breakfast cereal shows an abundance of vitamin and minerals, many of which have been added through fortification.

Cereal made contributions to adult as well. One study shows that breakfast consumption patterns of adult aged 50 and over and concluded that for all age and sex classes, consumption of ready to eat cereal at breakfast increased the average daily intake of all vitamins and minerals particularly those identified as under consumed by elderly individuals.

Adding milk or yoghurt makes cereal a great vehicle for delivering calcium and other nutrients in milk.

For this reason, cereal labels often give the Nutrition Facts for cereal only and for cereal with added milk.

With consumer awareness of the importance of whole grains, granolas have become popular, These typically contain vegetable oil to make them tastier. Thus a cup of commercial prepared granola can easily provide 600 calories or more.
Cereal nutrition and diet

Listeria monocytogenes

2012-05-07T02:12:00.007-07:00

The genus Listeria is a gram positive, microaerophilic, non-sporeforming rod. Listeria monocytogenes is a hazardous foodborne microorganism of relatively recent concern.

It commonly observed in the environment where they developed highly adaptive characteristic during their evolution.

The disease is more likely to occur in certain susceptible populations (i.e. pregnant mothers, newborns, immune-compromised people, transplant recipients, etc).

Foodborne listeriosis represents a relatively rare but clinically serious disease, with high case fatality rates (20-30%) that largely specific segments of the population with increased susceptibility.

Fatalities rates with the more severe forms of listeriosis can be high as 70% for those untreated.

Although relatively uncommon, Listeria monocytogenes are almost exclusively foodborne (99%), and are mainly caused by the consumption of contaminated food products.

Listeriosis has been associated with the consumption of a variety of contaminated foods including soft cheese, raw milk, hot dogs, delicatessen meats and salads, seafood and fresh vegetables.

Its widespread distribution in the environment and foods. Its ability to multiply at refrigeration temperature and cause severe illness make it a hazard of particular concern to the food industry.

HACCP program should attempt to destroy, eliminate or reduce this hazard, and prevent the opportunity for subsequent recontamination.

Listeria monocytogenes

Chemical composition of papaya

2012-05-01T22:55:00.004-07:00

Analysis of the fruit gave moisture 89.6 %, proteins 0.5%, carbohydrate 9.5%m, ether extract 0.1%, mineral matter 0.4%, calcium 0.01%, phosphorus 0.01%, and iron 0.4 mg/100 gm.

The high content of water in the papaya almost as a melon (92%), This is why some call it the ‘tropical melon’.

The chemical composition of papaya fruit with respect to sugars, organic, amino acids, vitamins, and minerals change during ripening.

Most of its carbohydrates are formed from sugars: saccharose, glucose and fructose.

The fresh fruit pulp contains sucrose, invert sugar, a resinous substance, papain, malic acid and salts of tartaric and citric acids 1.2 per cent.

The dry matter which was 7% at 15 days after pollination, increased to 13% at harvest.

Both ripe and unripe papaya fruit is a rich source of pectins.

Papaya is a source of calcium, and an excellent source of vitamin A and C. The B vitamins are also present in small amounts.

Papaya’s fruit and seed have been shown to possess bactericidal activity against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa and Shigella flexneri.

Chemical composition of papaya

Selenium and vitamin E complementary roles

2012-04-29T17:46:00.000-07:00

Selenium’s principal function is to inhibit the oxidation of lipids (fats) as a component of the intracellular enzymes glutathione peroxidase.

It is a vital antioxidant, especially when combined with vitamin E. It protects the immune system by preventing the formation of free radicals and destroys lipid peroxides that form and are released into cells.

Oxidation is the metabolic process by which fats, carbohydrates and preteens are converted to carbon dioxide, water and energy, burned to produce the energy needed for body functions.

However, oxidation of the body’s structural and functional component is harmful. The body must have a antioxidant defense mechanism to protect it from oxidation-induced damage. Selenium have a closely associated with vitamin E in its mode of function as a major component of this mechanism.

Glutathione peroxides occurs mainly in the cytosol and reduces peroxides before they can attack cell membranes, whereas vitamin E acts within the membrane itself as a second line of defense.

Selenium deficiency and vitamin E deficiency are so interrelated that it is usual to refer to the diverse group of disorders ascribed to their deficiencies as vitamin E-selenium deficiency.
Selenium and vitamin E complementary roles

Nutrient in egg yolk

2012-04-25T22:51:00.001-07:00

An egg has two parts – egg white and egg yolk. The central part of the egg is the egg yolk and the yolk is surrounding by a thin covering called vitellin membrane.

The yellow portion makes up about 33 percent of the liquid weight of the egg.

The egg yolk is rich in fat, that is about one third of the yolk is fat, especially of cholesterol and lecithin variety.

Egg yolk lecithin is a key source of compounds known as phospholipids, which are crucially important molecules with active roles in cell membranes particularly in the brain and nervous system.

The yolks of chicken eggs produced commercially contain large amounts of the carotenoid lutein and zeaxanthin (approx. 292 ug/yolk and 213 ug/yolk, respectively).

Several studies have linked lutein to a lower risk for eye, skin and other health disorders, probably though its antioxidant activity.

Lutein and zeaxanthin may protect the cardiovascular system and maintain normal cell differentiation in the tissues of the breasts, colon, and skin.

Some research into the health benefits of eggs suggest a link between eggs and a reduced risk of heart attack or stroke, primarily because the protein in egg yolk help prevent blood clots.

Egg yolk also is rich in vitamins, especially thiamin, riboflavin, vitamins A and D and their content in eggs upon the chicken’s diet. Egg yolk are one of the few foods naturally containing vitamin D.

The yolk’s content of phosphorus, manganese, iron, iodine, copper and calcium are higher than the whites and it contain all of the zinc.

Nutrient in egg yolk

Definition of flavoring substance

2012-04-24T01:48:00.000-07:00

Favoring substance can be defined as chemical component with flavoring properties, not intended to be consumed as such.

The legislation permits the use of any flavoring substance which is wholesome and presents no hazard to health.

Flavoring substances may be classified as:
*Natural flavoring substance
*Natural identical flavoring substance
*Artificial substance
*Flavoring preparation
*Process flavorings

Natural flavoring substance are obtained by appropriate physical, microbiological or enzymatic processes from a food stuff or material of vegetable or animal origin as such or after processing by food preparation processes.

When flavor compounds are added to foods, no health hazards should arise from the concentrations used.

The flavor contains flavoring substance and solvents or carries, the concentration of a single flavoring substance in the food does not usually exceed 10-20 ppm.

Historically flavoring substances have been tested for safety by testing representatively members of a chemically similar group.

Many flavoring substances are self-limiting and are typically used at very low concentrations to impart their desired effect and exposure from their use in foods is, generally, very low.

Like all other food additives, both natural and artificial flavoring substances are regarded as foreign substances and may not be use unless specifically permitted in the regulation governing each group of food products.
Definition of flavoring substance

Niacin deficiency

2012-04-21T18:47:00.000-07:00

First documented in 1735 by a Spanish physician named Gaspar Casal the niacin deficiency disease pellagra was originally named ‘mal de la rosa,’ or ‘red sickness.’ Its due to the telltale redness that appears around the necks of people with the disease.

Pellagra means ‘rough skin’ in Italian. The great pellagra epidemic in America’s South did not emerged until the early twentieth century.

Because the niacin coenzymes NAD and NADP are involved in just about very metabolite pathway, niacin deficiency wreaks havoc throughout the body. It also that the depressive psychosis is assumed to be because of inadequate formation of the neurotransmitter serotonin as a result of tryptophan deficiency.

The classical features of endemic pellagra are dermatitis, inflammation of the mucous membranes, diarrhea and psychiatric disturbances.

The dermatitis often appears after exposure to sunlight and resembles sunburn.

Pellagra condones to plaque people living in Southeast Asia and Africa however, whose diet lack sufficient niacin and protein.
Niacin deficiency

HACCP Programs

2012-04-19T19:59:00.000-07:00

HACCP programs should be strictly related to food safety.

Critical Control Points should only be used to control those points in a process where lack of control will likely result in the development of a potential safety hazard.

They should not be used to control non hazardous situations which are of serious regulatory, consumer or economic consequence.

Too much monitoring (i.e. inclusion of non-hazardous points) will dilutes out the HACCP effort, resulting in nothing being monitored or the wrong points being monitored.

There will be then no insurance that the product being release meets all safety requirements and therefore, a potential hazard may be delivered to consumers.

Non-safety related monitoring procedures should be part of a standard quality assurance programs.
HACCP Programs

Nutrition of date palms fruit

2012-04-17T07:57:00.005-07:00

The unique characteristic of date palm (Phoenix dactylifera L.) can be truly called a tree of life and is considered one of the most ancient plant cultivated in Mesopotamia some 4,000 years ago.

Dates are the fruit of the date palm and tastes sweet. Dates are dark brown , oval, and about 1-1/2 inches long. Its skin wrinkled and coated with a sticky, waxy film.

Date palms fruits are eaten as raw dates, dry dates and soft dates. Dates are highly nutritious and delicious.

Date fruits are rich spruce of sweeteners, glucose and fructose. Date syrup studies shows that it is mainly composed of reduced sugar: glucose and fructose as major source of sugar fraction.

The fully ripe fruits contain 75-80% sugars. As ripening progresses, then sucrose is hydrolyzed into ‘invert’ or ‘reducing’ sugars, a mixture of glucose and fructose, depending upon variety, cultural practices and other factors.

Soft and semi dry dates are primarily of the reducing sugar type (giving higher levels of sucrose hydrolyzed), while dry dates are mostly of the sucrose type.

Dates also good sources of iron, potassium calcium, magnesium, sulphur, copper and phosphorus, along with various vitamins, including thiamine, riboflavin, biotin, folic and ascorbic acid. The date palm fruit possesses antioxidant and antimutagenic properties in vitro.

Dates also contain tannins that are made mainly of polyphenols and two groups of them (phenolic acids and condensed tannins) are thought to be important on producing the astringent sensory response.

The tannin responsible for astringency of dates and their content decreased a maturity progressed.

Nutrition of date palms fruit

Bread as a nutritious food

2012-04-13T08:12:00.000-07:00

Healthy concepts related to nutritional value are emerging as fundamental quality attributes of bread products.

Bread is a nutritious food. It is starchy food that contains other vital nutrients. It is recommended to eat six slices of bread a day.

The excellent bread can be made from with flour, yeast, salt and water. Of the four ingredients, flour is the only variable, and the nutritional value of that will change according to the extraction rate or by addition during milling.

The nutritional value of bread can be increased by such addition as fat, milk, sugars, malt fruit and nuts.

Despite the fact that the nutritional composition of bread varies with the type of bread, bread is an energy dense product due to the carbohydrate content in the form of starch.

Bread is particularly important as an energy for food, providing 20-30% of the total energy requirements of the people.

It has 70 calories in an average slice. In some tests overweight people have succeeded in shedding pounds on diets of 1,200 to 1,500 calories of which almost half were from bread.

In term of protein, bread has an approximate protein content of 8%. About 20% of the protein intake of the people is provided by the bread baker. It is the cheapest source of protein.

It is also provide the amount of dietary fiber and does not contain cholesterol.

Although breads may appear similar, their ingredients vary widely. Breads made mostly from whole-grain flours provide more benefits to the body than breads made of enriched, refined, wheat flour.

Some ‘high fiber’ breads may contain purified cellulose or more nutritious whole grains. Low carbohydrate breads may be regular white bread thinly sliced to reduce carbohydrates per serving, or may contain soy flour, barley flour, or flaxseed to reduce starch content.

Whole grains breads provided the kind of dietary fiber that reportedly helps prevent such intestinal problems as constipation, diverticulosis and cancer of the colon.
Bread as a nutritious food

Disaccharides in food

2012-04-11T09:42:00.006-07:00

Disaccharides consist of two monosaccharides linked together with a special linkage, called a glycosidic bond. The following disaccharides are important in human nutrition: sucrose, lactose and maltose.

Sucrose or table sugar is the most common and contains glucose and fructose. It is commonly known in households and is found in many plant fruits and saps.

Chemically sucrose is one glucose molecule and one fructose molecule linked together.

Galactose seldom found free in nature, galactose is part of lactose, the sugar found in milk. Lactose is composed of one molecule of glucose and one molecule of galactose.

About 5% of fluid milk is lactose, or milk sugar. Human milk has a higher concentration of lactose than cow’s milk, so human tastes sweeter than cow’s milk.

Maltose is formed by the enzymatic hydrolysis of starch and is an important component of the barley malt used to brew beer.

Maltose also primarily used in the production of breakfast cereal and in some infant formula. It is a homogenous disaccharide consisting of two units of glucose.

Disaccharides in food

Pizza

2012-04-08T00:17:00.007-07:00

Pizza essentially is bread dough with other ingredients added. If the pizza is to be thin a dough is needed that spreads rather than lifts. If the pizza is to be thick then the dough needs to be nearer to British or American bread dough.

A pizza crust achieves its prominent characteristics – texture, tenderness and pliability – in large part from the type of the flour used. Quite simply, the higher the protein level in a flour, the greater the formation of gluten.

To make pizza base the ingredients are including flour, water, yeast, salt, olive oil and sugar are mixed together.

In order to produce high quality pizza products, the dough should be elastic and sheetable, rises on proving and holds the gas produced by the yeast as well as having good crust and textural properties.

In addition to the viscoelastic property of pizza dough, it should be firm enough to hold toppings without fallen apart.

Pizzas from different regions are often defined by the style or texture of the crust which is a direct result of the type of flour used in that region.

When making our own pizza, the topping can be tailored to suit our tastes. With lean meat or seafood, low fat cheese, and plentiful vegetables, it becomes a healthy one dish meal.

Pizza

Minerals content in cow’s milk

2012-04-07T17:56:00.000-07:00

Milk is an important source of growth supporting minerals, such as potassium, magnesium, phosphorus and zinc.

These minerals are especially important during catch up growth after a period of weight loss.

Mineral in milk are mainly present as soluble salts or in colloidal form associated with caseins.

Milk contains about 30 different minerals, but only a few of them are present in greater than trace amounts.

The mineral and trace elements content of cow milks is not constant but is influenced by a number of factors, such as stage of lactation, nutritional status of the mother, and environmental and genetic factors.

The two most abundant are calcium and phosphorus.

Although milk is rich in calcium, it may not be the best way to obtain this mineral. The dosages appropriate for the needs of small calves not for human beings.

Calcium constitutes about 30 percent of the total minerals in milk. In turn, about 30 percent of the total calcium is soluble.

Cow milk contributes a little to dietary intakes of sodium, but some dairy products, such as chesses and butter contain added salt and can be significant sources of sodium in some countries.
Minerals content in cow’s milk

Food Packaging

2012-04-05T08:24:00.000-07:00

At its most basic, packaging preserves and protects food and makes it portable.

Efficient packaging is necessary for every kind of food, whether it is fresh or processed. It is essential link between the food producer and the consumer, and unless performed correctly the standing of the product suffers and and customer goodwill is lost.

Food is package for the following reasons:
*For hygienic storage and transport
*To protect it from damage during storage and transport
*To give information to customers
*To attract customers
*For customer convenient

Food packaging also offer tamper-evident or temper resistant features, allow for product preparation and provide dispensing features and many convenient such as single serving potions.

As food products were distributed, they required identification and labeling. Also the design, shape and from of the package gained in importance.

The food industry uses four basic packaging materials: metal, plant matter –paper and wood, glass and plastic.

A number of basic packaging materials are often combined to give a suitable package. However the earliest food packaging was made from objects found in nature, such as hollowed-out gourds and empty seashells.

Proper food packaging of food is essential to make sure the food remains wholesome during its journey from processor to consumer; packaging also increase shelf life, an important consideration for food producers and marketers.
Food Packaging

Food additives: functions and the principles

2012-03-29T05:17:00.000-07:00

At the turn of the century, changes in population from agriculture to industrial had resulted in a need to establish distribution systems to supply the growing population of the cities with food.

Therefore, food additives are used to preserve the quality of the food and maintain its appeal and at times to restore diminished nutritional value.

It is added to food during its production, processing, treatment, storage or packaging. Some additives are used to change a food’s color or maintain its natural color. Other additives prevent food from spoiling or increase a product’s nutritional value.

According to expert, food deterioration results when the food supply is more than the consumption.

Deterioration can also accrue during the long time required in transit or during storage before it actually reached the consumers.

The current forms of food production and distribution have increased the demand for longer shelf life. Furthermore, the world food supply situation requires preservations by avoiding deterioration as much as possible.

The quality of food can be affected by physical, chemical, biochemical and microbiological processes.

The addition of permitted chemicals substances or food additives can prevent or greatly impede the process of deterioration.

A few principles governing the use of a food additive:
*Technological effective
*Safe in use. Food additives and their degradation products should be non-toxic at their recommend levels of use.
*Absolutely necessary quantity
*Never with the intention of misleading the consumer about the nature or quality of a food
*Minimum use of non-nutrient food additive. They are added to the food in carefully controlled amounts during processing.
*The additives are applied only when required for the nutritive or sensory value of food.
Food additives: functions and the principles

Bread baking principle

2012-03-28T19:55:00.000-07:00

The function of baking is to present cereal flours in an attractive, palatable and digestible form.

Most bakery products are made of the same few ingredients – flour, shortening, sugar, eggs, water or milk and leavenings.

The dough is kneaded by hand or machine. After the dough rests for some time (about 2 hours) it is manipulated to push out the gas that has been evolved.

Three process are commence when the ingredients for bread making are mixed.
*The protein in the flour begin to hydrate and to combine with some water , to form gluten.
*Air bubbles are folded into dough. During the subsequent handling of the dough these bubbles divide or coalesce.
*Enzyme in the yeast start to ferment the sugars present in the flour and later sugar released by diastatic action of the amylases on damaged starch in the flour, breaking them down to alcohol and carbon dioxide.

The dough is then moulded into loaf shape and allowed to rest in the baking pan for 45 to 60 minutes at 38° – 48° C for final proof and is then baked for about 30 minutes with steam injected into the oven to produce a glaze on the crust.

Loaf sized are breads is baked in an oven pre-heated to 204° C. After the first 15 minutes of baking, the temperature is reduced if the crusts become to brown. Baking is continued until the bread is fully baked.

There are four major changes to the dough piece which can be seen as it is baked:
*A large reduction in product density – the dough gets thicker, associated with development of an open porous or flaky structure
*A change of shape associated with shrinkage or spread and increase on thickness
*A reduction in moisture level, to between 1-4%
*A change in surface coloration
Bread baking principle