Milk proteins improvement

Another product, defatted com germ flour was coextruded at 150 or 170 °C with 5% milk protein to produce a puffed nutrient snack (Peri et al., 1983). The addition of fhe milk profein af fhe lower temperature improved the organoleptic characteristics of fhe exfrudafes but adversely affected the product expansion and consistency of fhe samples at the higher temperature. 

Field Pea Flour in Other Baked Products. When McWatters (44) substituted 8% field pea flour and 4.6% field pea concentrate for milk protein (6%) in baking powder biscuits, sensory attributes, crumb color, and density of the resulting biscuits were adversely affected. No modifications were made in recipe formulation when pea products were incorporated. The doughs were slightly less sticky than control biscuits that contained whole milk. This might be due to lack of lactose or to the different water absorption properties of pea protein or starch. Panelists described the aroma and flavor of these biscuits as harsh, beany and strong. Steam heating the field pea flour improved the sensory evaluation scores, but they were never equivalent to those for the controls. 

Guidry, A. J. and Pearson, R. E. 1979. Improved methodology for quantitative determination of serum and milk proteins by single radial immuno-diffusion. J. Dairy Sci. 62, 1252-1257. 

It is generally accepted that the higher the developed acidity, the lower the heat stability of the milk. The many factors involved are reviewed by Fox and Morrisey (1977). Heat stability of acid milks is improved by anion exchange (Tikhomirova et al. 1979). However, increased acidity resulting from increased protein, phosphorus, or calcium does not cause as serious a problem in normal milks (Sebela and Klicnik 1977). 

Enzymatic hydrolysis of food proteins yields peptides that are of great interest to the food industry and are utilized for various purposes, e.g., improving the functional properties of foods, parenteral feeding (casein hydrolyzates), or milk protein substitutes in cases of intolerance. 

Since the introduction of HPLC in the field of protein analysis, this technique has become very popular because of its versatility. The development of improved or new packing materials has often resulted in a decrease in the analysis time. However, with regard to the analysis of food proteins, the application of HPLC has remained limited mainly to wheat proteins and milk proteins. A quick survey of recent literature confirms this observation, and most publications about the... 

MILK PROTEIN MODIFICATION TO IMPROVE FUNCTIONAL AND BIOLOGICAL PROPERTIES... 

Improvement of functional properties of milk proteins by esterification... 

Sitohy, M., Chobert, J.-M., and Haertle, T. 2001c. Improvement of solubility and of emulsifying properties of milk proteins at acid pHs by esterification. Nahmng 45, 87-93. 

Several workers have chemically modified milk proteins ( c-casein, casein) to determine the chemical basis for the stabilization of the casein micelle by c-casein and to elucidate the mechanism of rennin action (35,36). Creamer et al. (37) made several derivatives of sodium caseinate and showed their improved solubility. In preliminary feeding trials in which succinylated casein was the only protein source, supplementation with lysine was required for the normal growth of rats. 

Zinc absorption was measured from meals based on wheat bread. A lower absolute amount of zinc was absorbed from a low zinc white bread (72% extraction rate) than from a whole-meal bread with a higher zinc content (100% extraction rate). When the two types of bread where enriched with zinc chloride, more zinc was absorbed from the white bread. By increasing the zinc content of the whole meal bread in form of animal protein sources, such as milk and cheese, the absorption increased to the same level as that from zinc-enriched white bread. Addition of calcium in the form of milk products improved the absorption of zinc from a meal with whole meal bread. 

For the analysis of spectinomycin in milk [56], acid protein precipitation and analyte extraction was combined with SPE, ion-pair LC with HFBA as ion-pair agent, and multi-stage ESI-MS-MS on an ion-trap instalment. [M+H+HjO] at m/z 351 was fragmented to yield [M+H] at m/z 333 in the first stage of MS-MS and further fragmentation of [M+H] in a second stage of MS-MS. The estimated confirmation limit for spectinomycin was 100 pg/kg milk. Further improvement of this method, especially with respect to variability of the ion-trap performance, is required to meet regulatoiy demands. 

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