Vitamin C: Essential micronutrient

Vitamin C is an essential micronutrient required for normal metabolic functioning of the body and perhaps the most publicized vitamin. Vitamin C supplies electrons to enzymes that required metal ions. It also acts with the substances prolyl and lysyl hydroxylases on the manufacturer of collagen.

To the best of scientific knowledge, all animals and plants synthesize their own vitamin C, except for a small number of animals, including guinea pigs, humans, apes, the red-vented bulbul, a fruit eating bat and a species of trout, that cannot.

Two forms of vitamin C occur in nature: ascorbic acid (the reduced form), and dehydroascorbic acid (the oxidized form). Although most of the vitamin C exists as ascorbic acid, both forms appear to be utilized similarly by the human.

Vitamin C is readily and rapidly absorbed from the upper part of the small intestine into the circulatory system. Thence, it is taken unevenly by the tissues; the adrenal gland and the retina of the eye contain an especially high concentration of vitamin C, but the liver, spleen, intestine, bone marrow, pancreas, thymus, pituitary and kidney also contain appreciable amounts.

Probably the most well known of all vitamins C’s benefits are to powerful antioxidant properties that protect the body from the damaging effects of oxidation. It readily scavenges reactive oxygen, nitrogen and chlorine species, thereby effectively protecting other substrates from oxidative damage.

Vitamin C is also critical to immune function, the manufacture of certain nerve transmitting substance and hormones and the absorption and utilization of other nutritional factors.

In 1974, Cameron and Pauling suggested that vitamin C might play a role in the supportive care of cancer patients. Vitamin C may protect against carcinogens such as nitrosamine. This chemical is formed in the body from nitrates and nitrites found in processed meat products such as lunch meats and hot dogs.

Vitamin C is an efficient water soluble one electron reducing agent that would be predicted to have efficacy in preventing oxidative DNA damage.

The stability of vitamin C is of main concern because this is the most labile vitamin in foods. Its main loss during processing and storage is from oxidation, which is accelerated by light, oxygen heat, increased pH, high moisture content and the present of copper or ferrous salts.
Vitamin C: Essential micronutrient

Iodine deficiency disorders

Iodine deficiency disorders (IDD) are the most important single preventable cause of brain damage and mental retardation worldwide.

It is estimated to affect more than 700 million people, most of them located in the less developed countries.

An iodine deficiency can lead to simple goiter – enlargement of the thyroid gland, and can impair fetal development, causing cretinism.

Cretinism affects approximately 6 million people worldwide and can be averted by the early diagnosis and treatment of maternal iodine deficiency.

Iodine, named after the Greek word for violet, was first observed as a violet vapor during the making of gunpowder at the beginning of the century.

The term iodine deficiency disorders refer to all the ill-effects of iodine deficiency in a population that can be prevented by ensuing that the population has an adequate intake of iodine.

Universal salt iodization (USI) is the main intervention strategy for iodine deficiency control, and was adopted by the International; Conference on Nutrition in 1992, reaffirmed by the World Health Assembly in 1993.
Iodine deficiency disorders

The nutrition of fruit juice

Fruit juice is a natural juice pressed out of a fruit and is unaltered in its composition during its preparation and preservation. It is important in human nutrition for beyond its use as a refreshing source of liquid. The juice can be part of a healthy diet.

Many fruits contain a variety of minor ingredients, particularly vitamins and minerals, as well as carbohydrates which are the predominant solid component.

Although fruit contains small amounts of protein and fat, these are not important ingredients of juices.

The more colorful the juice is or the darker its color, the more nutritious the juice. One example is pink grapefruit, which contains two chemicals that function as antioxidants and phytochemicals not found in regular grapefruit: lycopene and beta carotene.

Several components with antioxidant activity are found in fruit juices. These are including ascorbic acid, tocopherols (vitamin E), beta carotene and flavonoids.

Beta carotene has antioxidant activity that can quench the singlet oxygen that can induce precancerous cellular changes.

Cranberry juice products available commercially vary extensively, but 10-12 ounces of 27 percent cranberry juice per day is protective against urinary tract infections.

Cranberry juice conations the phytochemical polyphenol, which is believed to protect against heart disease and cancer.

Fruit juices are highly nutritive beverages and are rich in vitamins, minerals and other nutrients. Besides, they are delicious and have a universal appeal for their taste, aroma, flavor and color, when freshly expressed.
The nutrition of fruit juice

Interaction of Iron with Other Nutrient

Iron is present in all cells of the body and plays a key role in many biochemical reactions.

There is no evidence that humans are ingesting sufficient zinc to induce anemia. On the other hand, excessive iron supplementation is often a practice among humans and this excessive intake of nonheme iron may have detrimental effect on zinc nutrition.

It is believe that the basis of interaction between these two minerals is their competition for some portion of a common absorptive pathway.

As a general rule, excessive concentration of one divalent ion in the gastrointestinal tract may inhibit absorption of other divalent ions. Conversely, a deficiency of one divalent ion may enhance the absorption of others.

Absorption of iron is hindered by fiber and phosphate and prompted by ascorbic acid, copper and meat proteins.

Copper and iron may interact in numerous ways. At the metabolic level, an interrelationship appears to exist between iron and copper because the role of copper containing ceruplasmin as feroxidase.

Anemia, often accompanied by accumulation of iron in the liver, has been reported on all species studied, including human. Excessive iron in the form of inorganic iron salts decreased copper status and in time resulted in clinical signs of copper deficiency in several animal species.

Also ascorbic acid and iron are interrelated on that activation of several deoxygenases by ferrous iron appears dependent on the presence of ascorbate.

Absorption of iron is controlled strictly, and excretion of iron is limited. Protein is one of the major participants in the tight regulation of iron: bioavailability of dietary iron is influenced by concomitantly ingested proteins; dietary patterns and protein status affect iron status; additionally, specialized proteins are instrumental in iron absorption and transport.
Interaction of Iron with Other Nutrient

What are nutrient compositions in cereal grains?

Cereal grains are major food and feed source. The top three stable food grains –rice, corn and wheat – represent over 50% of the human food source.

Nutrition composition of cereal grain may vary from one region or year to the next because of differences on plant genetics or environment.

In composition, grains are structurally similar as seen; however, they vary in their nutrient composition, containing varying amounts of carbohydrate, fat, protein, water, vitamins and minerals.

The nutritional value of the grains is determined by the nutrient amount and composition in the grains that accumulate during grain filling and by the bioavailability of micronutrients.

Carbohydrate 
The main nutrient component of cereal grains is carbohydrate which makes up 79-83% of the dry matter of grain.

Cereals contain small amounts of free sugars of the order of 1-2% although this will rise if the grain has been allowed to germinated, e.g. in the preparation of malted cereals.

It exists predominantly as starch, with fiber especially cellulose and hemicellulose, composing approximately 6% of the grain.

Lipid 
Lipids are relatively minor constituents in cereal grains. Lipid (fats and oil) makes up approximately 1-7% of a kernel, depending on the grain. For example, wheat rice, corn, rye and barley contain 1-2% lipid, oats contain 4-7%. The lipid is 72-85% unsaturated fatty acids, primarily, oleic acid and linoleic acid. 

Protein 
Protein composes 7-14% of the grain, depending on the grain. Cereals are low in the amino acids tryptophan and methionine, and although potential breeding may produce cereals higher in the amino acid lysine, it remains the limiting amino acid in cereals.

The protein is of low biological value and therefore, less efficient in supporting body needs.

Protein in cereal grains can be divided into two broad groups based on their biological functions: biologically active enzymes and biologically inactive storage proteins.

The storage proteins make up most (up to 80%) of the total proteins.

Vitamins 
Vitamins present in cereals are predominantly the B vitamins-thiamin (B1), riboflavin (B2) and niacin (B3). These vitamins may be lost in the milling process and so are added back through the process of enrichment. 

Whole grain products contain some fat soluble vitamins in the germ. When considered as a whole, cereals are naturally low in lipids therefore, they tend to be low in the fat soluble vitamin A, which is present as the precursor carotenoids and vitamin D, E and K.

Water 
Water is present in cereal grains at levels of 10-14% of the grain. Of course soaking and cooking add water to cereal grains, and the grain size expands as additional water is absorbed. If flour is high in protein content, it absorbs a lot of water compared to low protein flour.

Mineral 
Mineral are naturally present at higher levels in whole grains than in refined grains. Fortification of refined flour with added iron is common.

Zinc, calcium as well as vitamins also may be added at levels beyond not present in the original grain. 

Fiber 
Fiber content is determined by different analysis and includes crude fiber (CF) and total dietary fiber (TDF).

These two measurements are not correlated. Crude fiber is composed of cellulose and the non-carbohydrate lignin. TDF includes cellulose and lignin, plus hemicellulose, pectic substances, gums and mucilages.
What are nutrient compositions in cereal grains?

Moisture content in fish

Water is the principle component (up to 80%) of the edible portions of seafood.

Among fish researchers there is no such accepted norm. Moisture content may be reported on a dry basis, a wet basis, a salt-free basis and often the basis is not specified.

However, mostly moisture content is expressed in a wet-weight basis – i.e., is the mass of water in a unit mass of the fish. Moisture contents range from 64.3 to 82.8 percent, with the exception of caviar; this range is very similar to that of mammalian species.

The moisture content of fish is usually determined by oven drying at 100 to 102° C for 16 to 18 hours; the loss of mass in that time being equated to the mass of water in the original sample.

The Karl Fisher method is probably suitable for material in which only a small percentage of moisture is present. But the method is hardly followed for fish and allied materials.

The method of storage as well as further processing, such as freezing determines the final moisture content of the fish flesh.

Considerable moisture, as well as soluble nutrients, may be lost in thaw drip. Water retention is highest in fresh fish. Finfish moisture contents generally show an inverse relationship to the lipid content.

Depth and latitude of fish catch also influence the moisture content of fish. Fish from deep water and from northern latitudes have higher moisture and lower fat content.

Raw shellfish moisture contents fall in the same range as finfish, but average is slightly higher, 80.1%. About one fourth of the moisture can be lost during cooking, which results in concentration of other components.
Moisture content in fish

Category of nutrients

The body is a complex system that has many nutritional demands. Nutrients are chemical substance present in food that are used by the body to sustain growth and health.

The average human body contains about 20 % of fat, 15% protein, much smaller amounts of carbohydrate (perhaps I %) and a large proportion of body mass consist of water.

Carbohydrates serve as the main source of energy for the body. The carbohydrate category includes simple sugars and complex carbohydrates such as starches and dietary fiber. Fiber is also a complex carbohydrate and is found in the walls of plant cells.

Human body also contains substantial amounts of the “major minerals,” from calcium and phosphorus down to sulfur and magnesium as well as trace quantities of most elements. In the context of nutrition, minerals consists of 15 element found in foods that perform functions in the body.

The protein category includes 20 amino acids the chemical units that serve as the ‘building blocks’ for protein. The body needs food with protein to build and rebuild its cell. Human skin, teeth and bones are all parts of human body that require protein.

Vitamins are also essential to the function of the body, Some vitamins are dissolved in body fat and are stored in the body.

The human diet reflects this compositional need, and consists of large quantities of water containing, proteinaceous, fatty, and carbohydrate foods, as well as others rich in the minerals.

Category of nutrients 

Vitamin in Food

Vitamins are minor components of foods that play an essential role in human nutrition.

They are food substances contained in all living organisms and as such are absolutely necessary for proper growth and maintenance of health.

Many vitamins are unstable under certain condition of processing and storage and their levels in processed foods, therefore may be considerably reduced.

Synthetic vitamins are used extensively to compensate for these losses and to restore levels in foods. The vitamins are usually divided into two main groups, the water soluble and the fat soluble vitamins.

The occurrence of the vitamins in the various food groups is related to their water or fat solubility.

All vitamins found in liver and eggs are fat soluble, and those that are in fruits and vegetables are water soluble.

Some vitamins function as part of a coenzyme, without which the enzyme would be ineffective as a biocatalyst.

As catalysts vitamins speed up the processes in all living cells, plant and animal.

Some vitamins occur in foods as provitamins - compound but can be changed by the body into vitamins.

Lack of vitamins has long been recognized to result in serious deficiency disease. It can occur not only as a consequence of insufficient supply of vitamins by food intake, but an be caused by disturbances in resorption, by stress and by disease.

Almost all foods contain some vitamins and all the food groups contain foods that are good sources of a variety of vitamins. The sources of vitamins in significant amounts by food groups have been listed below:

*Meats, poultry, fish and beans provide thiamin, riboflavin, niacin, pyridoxine, pantothenic acid, biotin and vitamin B12.

*Milk contains both fat and water soluble vitamins. Milk and milk products provide vitamins A and D, riboflavin, pyridoxine and vitamin B12.

*Bread and cereals provide thiamin, riboflavin, niacin, pyridoxine, folate, pantothenic acid and biotin.

*Fruits and vegetables provide vitamins A and K. ascorbic acid, riboflavin and folate.

*Fat and oil provide vitamins A and E.

There are 13 vitamins in all, you need every single one of them, no exceptions.

No one food is a good source of all vitamins and as such a variety of foods should be consumed.

Some foods are very high in selected vitamins whereas some contain precursors or substances at serve as building blocks for many the vitamin in the body.
Vitamin in Food