Casein hydrolyzate

Casein hydrolyzates are produced from dried casein. With appropriate heat treatment and the addition of alkaHes and enzymes, digestion proceeds. FoUowing pasteurization, evaporation (qv), and spray drying, a dried product of 2—4% is obtained. Many so-called nondairy products such as coffee cream, topping, and icings utilize caseinates (see Dairy SUBSTITUTES). In addition to fulfilling a nutritional role, the caseinates impart creaminess, firmness, smoothness, and consistency of products. Imitation meats and soups use caseinates as an extender and to improve moistness and smoothness. 

FIGURE 8.13 SEC of casein hydrolyzates. Numbers above the peaks refer to the number of amino acid residues in the typical peptide in the indicated fraction. Column PolyHEA, 200 X 9.4 mm 5 /zm, 200 A. Flow rate 0.5 ml/min. Mobile phase 50 mtA Formic acid. Detection A250. Samples (A) Pancreatin hydrolyzate and (B) tryptic hydrolyzate. (Adapted from Ref. 29 with permission from Silvestre et of. Copyright 1994, American Chemical Society.)... 

The proteins in food supplements are often hydrolyzed to short peptides to make them easier to absorb. A high content of amino acids is deleterious, however. Thus, there is ongoing interest in determining the size distribution of peptides in protein hydrolyzates. Silvestre et al. (29,30) used a PolyHEA column to compare casein hydrolyzates prepared through various methods. They were able to assess the content of the smallest peptides, as well as amino acids (Fig. 8.13). 

Fe" (2 ppm), casein hydrolyzate (0.2 g/dl), yeast extract (0.2 g/dl), corn steep liquor (0.2 ml/dl), polypeptone (0.1 g/dl), meat extract (0.1 g/dl) and sodium ribonucleate (10 mg/dl) were poured into respective test tubes and each tube was sterilized at 115°C for 10 minutes. Thereafter separately sterilized calcium carbonate was added in the amount of 2 g/dl and then cells of Bacillus subtUis S26910 were Inoculated into the above media and cultured with shaking at 30°C for 20 hours. 

Nitrogen sources include proteins, such as casein, zein, lactalbumin protein hydrolyzates such proteoses, peptones, peptides, and commercially available materials, such as N-Z Amine which is understood to be a casein hydrolyzate also corn steep liquor, soybean meal, gluten, cottonseed meal, fish meal, meat extracts, stick liquor, liver cake, yeast extracts and distillers solubles amino acids, urea, ammonium and nitrate salts. Such inorganic elements as sodium, potassium, calcium and magnesium and chlorides, sulfates, phosphates and combinations of these anions and cations in the form of mineral salts may be advantageously used in the fermentation. 

Salt-free hydrochloric acid hydrolyzate of casein, Baltimore Biological Laboratory Inc., Baltimore, Maryland. These casein hydrolyzates can be substituted by Casamino acid (Difco), enzymatically hydrolyzed casein or acid-hydrolyzed casein. 

Rheum palmatum Callus culture was induced from petiole of plant cultivated in vivo on the Murashige-Skoog (MS) medium (Murashige and Skoog, 1962) gelled by agar (8g/l), supplemented with naphthaleneacetic acid (NAA) (10 mg/1) and casein hydrolyzate (2 g/1). Callus subcultured every 4 weeks was transferred into the liquid medium and filtered through a sieve (mesh 3 mm). 

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. 

Using the rat as a test object, the authors found that of a number of aminelike and other pressor compounds only one, phenylethylamine, had a prolonged action (5 to 30 minutes) on blood pressure (Table III). Of the others renin had only a relatively long action (5 minutes or less), while isoamylamine, tyramine, epinine, arterenol, hypertensin, casein hydrolyzate, epinephrine, and tryptamine had only a short action (2 minutes or less). Phenylethylamine therefore may be an example of either (1) or (3). This was an unexpected result, and suggests further the importance of certain amine pressor agents. DOPA, although not an amine, also had a prolonged action. 

Casein hydrolyzate 100 35/24 <1 Immediate rise followed by depression... 

Siitas, Y., Soppi, E., Korhonen, H., Syvaoja, E.L., Saxelin, M., Rokka, T., and Isolauri, E. 1996. Suppression of lymphocyte proliferation in vitro by bovine caseins hydrolyzed with Lactobacillus casei GG-derived enzymes. J Allergy Clin Immunol 98 216-224. 

The proteins of milk are made up of caseins and whey proteins. Milk proteins, caseins, and several enzymes, mainly hydrolases and oxidoreductases, are very important in the manufacturing of cheeses and yogurts (Figure 2.3). After drying they are used in the food industry as milk powder, caseinates, and casein hydrolyzates. Nonprotein nitrogenous compounds constitute about 0.2% of milk.. 

Protein Intake and Urea Excretion. Levin et al. (L7) were the first to show that urea excretion and therefore presumably urea synthesis was increased with increased protein intake in argininosuccinic aciduria. They showed in their patient that an increase of 2.5 times in the protein intake resulted in a 4- or 5-fold increase in urea output. From the results of a feeding trial, in which the infant was given a casein hydrolyzate from which most of the arginine had been removed, they concluded from the small amount of arginine present and the relatively high amount of urea excreted daily, that most of the urea was derived from a urea cycle, presumably in the liver. Conversely, reduction of protein intake resulted in a marked decrease in the output of both urea and argininosuccinic acid. 

In 1933, shortly following the discovery of phosphoserine (44), Schmidt, and Levene and Hill isolated from a casein hydrolyzate a dipeptide consisting of serine, glutamic acid, and phosphoric acid (38, 84). In 1941, Posternak and Pollaczek demonstrated the presence of a free a-amino group in the serine moiety of the molecule and assigned the following structure... 

Functional properties of some enzymatically modified and EPM-treated products of milk proteins [136] were determined as follows. An enzymatically prehydrolyzed commercial milk protein concentrate (SR) without further hydrolysis, and casein hydrolyzed by alcalase, a-chymotrypsin, and papain, respectively, were used as substrates in the EPM reaction. The concentration of the hydrolysates was 20% w/ v in the EPM reactions. A methionine methyl ester hydrochloride/ substrate ratio of 1 5 was used for incorporating this amino acid. After incubation, the products with methionine incorporation were simultaneously dialyzed for 2 days through a cellophane membrane against distilled water. The nondialyzable fractions and the EPM products without amino acid enrichment were freeze-dried. Covalent methionine incorporation in the EPM products with amino acid enrichment was verified by exopeptidase hydrolysis of the protein chains. The functional properties of the different EPM products are summarized in Table 1. An important functional property of proteins and/or peptide mixtures is their emulsifying behavior. This is highly influenced by the molecular structure, the position and ratio of hydrophobic-hydrophilic amino acids. Emulsion activity was found to be low (34.0) for casein, and the values determined for enzyme hydrolyzed and modified products were in general even lower. The papain hydrolysate, sample H3, showed here a different behavior as well this was the one of the sample series that had the highest EAI value (43.0). The emulsion stability of the enzymatically modified products displayed tendencies quite opposite to the values of emul-... 

I. Factors influencing production of volatile fatty adds from casein hydrolyzate. /. Dairy Sci. 48,287-292. 

The use of L-amino acids constitutes part of the therapeutic measure of parenteral nutrition, which also includes fat emulsions and carbohydrates, i.e., sugars. Only with mixtures of amino acids is it possible to provide physiologic intravenous protein feeding. The modern use of intravenous amino acid nutrition was initiated by Elman (1937), following studies on casein hydrolyzates. 

Methionine (methylthio group) from casein hydrolyzate by J.H. Mueller. Structure confirmed by synthesis G. Barger and F.P. Coyne, 1928. 

Hydrolyzed casein Hydrolyzed milk protein binder, nylon Epoxy-novolac binder, oil cosmetics Hydrolyzed rice protein binder, oil hair care Hydrolyzed rice protein binder, oil oil-absorbent formulations Hydrolyzed rice protein binder, oil skin care Hydrolyzed rice protein binder, oil-well sands Phenol-formaldehyde resin Phenolic resin binder, organic solvent systems Ethyl hydroxyethyl cellulose binder, outdoor paints Potassium silicate binder, paints... 

Hydrolyzed casein Hydrolyzed milk protein Isopropyl stearate Isostearyl isostearate PVP/eicosene copolymer PVP/hexadecene copolymer Sodium magnesium silicate binder, petroleum PEG-14M... 

Hydrolyzed casein . Hydrolyzed conchiorin protein Hydrolyzed corn protein Hydrolyzed DNA Hydrolyzed fibronectin Hydrolyzed gadidae protein Hydrolyzed gelatin Hydrolyzed hemoglobin Hydrolyzed lupine protein Hydrolyzed milk protein Hydrolyzed oat flour Hydrolyzed pea protein Hydrolyzed placental protein Hydrolyzed potato protein Hydrolyzed reticulin... 

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