Whey is the liquid part of milk that is obtained by coagulating and removing the curd (casein) during cheese production. After his separation from milk, whey, almost all vitamins and minerals, contains 50% milk solids, and 20-24% of milk proteins. The main protein fractions of whey are a-lactalbumin and ß-lactalbumin, which contain between 70-80% more of the whey protein fractions, glycomacropeptides, bovine serumAlbumin, lactoferrin, immunoglobulins, phospholipoproteins and other bioactive factors and enzymes.
Although the nutritional value of this protein was recognized and applied to animal feeding, delaying its application to human nutrition. Originally, the main weakness, since the serum has been only one heatdenatured form. Morr et al. reviewed a variety of techniques have been developed to produce denatured whey in commercial quantities. TheResults after generations of developing whey separation techniques include a whey protein concentrate (WPC) with a high protein content and low levels of minerals, fat and lactose.
In most protein foods is either the amino acid lysine or methionine plus cystine. Whey proteins are unique because they have a high level of essential amino acids (EAAs), are included lysine, methionine, cystine and branched-chain amino acidsAcids (leucine, isoleucine and valine). The excellent amino acid profile that led to the use of whey protein for medical disorders. WPC were exposed to various types of hydrolysis (enzymatic and pH-value) of whey protein hydrolysates (WPH) to create.
The use of acids and bases to hydrolyze whey can cause denaturation of essential amino acids, enzymatic hydrolysis, the method of choice. However, this method may be an incompleteHydrolysis and bitter tasting hydrolysates. The use of different enzymatic methods (ie, papain) can result in hydrolysates that are far less bitter tasting. The end products are of high quality (not provided) denatured amino acids and peptides and have received enormous attention not only from the scientific community, but life extensionists, athletes and health! Fitness enthusiasts as well.
Animal studies
To understand the mechanism of whey protein canexert their effects on protein synthesis must be studied different areas. These include the effects of whey on growth during development and recovery from stress or injury. Studies in vitro and in animals have examined the effects of whey protein on growth and development of recovery from severe burns or repair of the gastric mucosa. In general, the better for WPC calf growth and development than dried skim milk (DSM), when delivered as 67% or100% of the major protein source.
However, if a starter formula for both the WPC and DSM Nutrition, and added growth rates between the two diets similar. When studied as a substitute for colostrum in calves, WPC resulted in similar weight gain and a lower immune status of calves. From this brief summary can be concluded that whey protein concentrate is better than dry skin milk, colostrum, but not in relation to the growth and development ofCalves.
Poullain et al. Comparison of the effects of different molecular forms of whey, such as WPC, WPH or amino acid mixture (AAM) on growth and nitrogen retention in rats. The male Wistarrats were divided into six groups of eight. Three groups were for 72 hours before they returned to starve one of the three forms of whey ad libitum for 96 hours. The other three groups served as controls and received one of the three whey diets. Animals from starvationFeeding lost on average about 13% of their body weight. Although no differences were found in the control group, the WPH-refed group again, much faster than the WPC or AAM-refed groups. Urinary nitrogen excretion was much lower for both the referred and control WPH groups, in comparison to all other groups. This suggests that the mechanisms of the increased uptake of nitrogen is not to say, by the nutritional status (well influenced atrophy).
The improved Proteinanabolismus the WPHDiets were not associated with an increase in ureagenesis. The diets were in the fields of energy, nitrogen, amino acids identical, and nonnitrogenous nutrient content. The inclusion of the rats were all the same, therefore it is speculated that the different absorption rates and blood samples of amino acids, the reason for the differences in nitrogen balance between the WPH may be the WPC and AAM diets. These differences could be related to effects of the blood levels of amino acids on hormone production.Thus, by taking a WPH, with a sudden increase in blood levels of certain amino acids may trigger the release of insulin or any other anabolic hormone, leading to increased protein synthesis and greater nitrogen uptake.
Data from the previous study, which was published separately, examined the effects of WPH, WPC, AAM and food on the jejunal mucosa of controls versus starved refed rats. During the famine for 72 hours, was well and atrophy of villi height decreased. AfterReturn all diets resulted in repair of the fasting-induced gut atrophy. The WPC diet produces rapid repair and growth of the villi in the refed rats. The WPH and AAM diet produces better results in growth and villi disaccharidase activity in the control groups. The importance of this work is to demonstrate that enteral feedings can be changed by the different molecular forms of whey jejunal morphology and enzyme activity. The combination of data from the two PoullainStudies have found that increased body weight and positive nitrogen balance in WPH refed rats, although it appeared, had not undergone the same degree as the mucosal repair in the WPC refed rats. This is further evidence that the mechanisms by which whey protein has a positive effect on nitrogen balance and body weight may be the nutritional status independently.
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