Amino whey protein

Reactivity of Bovine Whey Proteins, Peptides, and Amino Acids toward Triplet Riboflavin as Studied by Laser Flash Photolysis. Journal of Agricultural and Food Chemistry, Vol. 52, No. 21, (October 2004), pp. 6602-6606, ISSN 0021-8561. 

Protein Portion of total whey proteins (%) Molecular weight (kDa) Amino acid residues... 

In some protein sources storage protein may be isolated from non-storage protein, or acid-precipitated proteins isolated from whey proteins. In the preparation of classical protein isolates by solubilization and acid precipitation, the amino acid make-up of the isolate differs from that of the extract. Consequently, consideration must be given to the amino acids chemically present in a refined protein. 

Isoelectric precipitation results in loss of whey protein as well as undesirable non-protein components. Gillberg (35) has shown that the cystine composition of the isolate is lower than for the meal extract because non-precipitated whey protein has a relatively larger proportion of the total sulfur amino acids. This observation is reinforced by Mattil (36), who showed that the range for amino acid composition was different for several commercial concentrates as compared to commercial isolates. He found methionine to be lower for isolates than for concentrates. 

Casein is low in sulphur (0.8%) while the whey proteins are relatively rich (1.7%). Differences in sulphur content become more apparent if one considers the levels of individual sulphur-containing amino acids. The sulphur of casein is present mainly in methionine, with low concentrations of cysteine and cystine in fact the principal caseins contain only methionine. The whey proteins contain significant amounts of both cysteine and cystine in addition to methionine and these amino acids are responsible, in part, for many of the changes which occur in milk on heating, e.g. cooked flavour, increased rennet coagulation time (due to interaction between /Mactoglobulin and K-casein) and improved heat stability of milk pre-heated prior to sterilization. 

The caseins are often considered to be rather hydrophobic molecules. However, consideration of the amino acid composition indicates that they are not particularly so in fact, some are more hydrophilic than the whey protein, /3-lactoglobulin (Table 4.2). However, the caseins do have high... 

Whey proteins are slightly superior to casein because of the limiting quantity of the total sulfur-containing amino acids (methionine plus cystine) in casein. However, because whey proteins have a relative surplus of these amino acids, casein and whey proteins, as found in milk,... 

Table B2.1.1 An Example Of Calculation For Amino Acid Score Using Whey Protein"...

See Table B2.1.1 for an example of the calculation for amino acid score using whey protein. 

Extraction of a portion of whey proteins, peptides, and amino acids Suitable for extraction of caseins and peptides from young cheeses. Not as effect as water Extraction of bitter and astringent peptides... 

The mechanisms of modification are different and depend on the chemical molecules used for the reactions. The anhydride of succinic acid reacts with lysine residues, a-amino groups of proteins and free thiol groups. During succinylation, proteins lose their globular structure and undergo aggregation by disulfide cross-binding with other whey proteins. Acetyl anhydride can modify tyrosine residues. 

The whey produced during cheese and casein manufacturing contains approximately 20% of all milk proteins. It represents a rich and varied mixture of secreted proteins with wide-ranging chemical, physical and functional properties (Smithers et al., 1996). Due to their beneficial functional properties, whey proteins are used as ingredients in many industrial food products (Cheftel and Lorient, 1982). According to Kinsella and Whitehead (1989), functional properties of foods can be explained by the relation of the intrinsic properties of the proteins (amino acid composition and disposition, flexibility, net charge, molecular size, conformation, hydrophobicity, etc.), and various extrinsic factors (method of preparation and storage, temperature, pH, modification process, etc.). 

Nutritional significance. As one of the major whey proteins in human milk and also relatively abundant in bovine colostrum, LF is of interest as a dietary source of amino acids as well as for the bioavailability of iron. LF has an... 

Studies on bovine whey proteins. IV. Amino acid analyses of crystalline / -lactoglobulins and lactalbumin by quantitative paper chromatography. Arch. Biochem. Biophys., 55, 315 (1955). With K. W. Weiss. 

Antibiotics, hormones, monoclonal antibodies, plasma proteins, insulin, vaccines, alkaloids Whey proteins, milk proteins, egg proteins, soy proteins, vitamins, amino acids, protein hydrolysates, yeast cells, yeast extract Glucose oxidase, peroxidase, hormones Detergent enzymes, insecticides Bovine serum albumin, ovalbumin, lysozyme Plant extracts, animal tissue extracts... 

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