DD297330A5 - METHOD FOR PRODUCING A PHENYL ALANINE-FREE PROTEIN HYDROLYZATE - Google Patents

Abstract

The invention relates to a process for the preparation of a phenylalanine-free protein hydrolyzate, which is free of humic substances and bitter peptides, which is characterized in that freshly washed and washed with whey protein by heat denaturation in 5 to 10% aqueous slurry with - based on dry protein - 1 to 2 * pancreatin at 48C and p H8 in 5 to 8 hours, then hydrolyzed with pronase under otherwise identical conditions to an amino acid oligopeptide mixture having a degree of degradation of 60% and then freed from phenylalanine by treatment with charcoal. {Protein hydrolyzate ; Preparation, phenylalanine-free; denaturation; Heat; Whey protein; Precipitation; pancreatin; pronase; Hydrolysis; Degree of degradation; Activated carbon}

Description

Anwendungsgablet the invention The invention relates to the production of a phenylalanine-free protein hydrolyzate for phenylketonuria diet foods. Characteristic of the known state of the art

Children and pregnant women who suffer from phenylketonuria (PKU) need food whose protein content does not contain phenylalanine. Since this amino acid occurs as a building block of all proteins, there is a need to largely hydrolyze suitable proteins, to remove the phenylalanine from the hydrolysates and to assemble dietary foods for PKU patients from the phenylalanine-free protein hydrolysates and other nutritional ingredients. The hydrolysis has hitherto mostly been carried out with mineral acids. Part of the amino acids is lost by decomposition; as far as essential amino acids, ζ. As tryptophan, the product must be supplemented with these. The decomposition products are humic substances which give the hydrolyzate a unpleasant taste in the long term. The phenylalanine is generally eliminated by multiple treatment with activated charcoal. Since the humic substances are also adsorbed to a large extent, the uptake capacity of the coal for phenylalanine decreases, so that the number of coal treatments increases.

One way out of this dilemma is provided by enzymatic hydrolysis, which in this case must be up to free amino acids and oligopeptides. Short-chain peptides containing the phenylalanine residue are also taken up by the activated carbon; but the other amino acids contained therein are lost as a result. On the other hand, a content of di- and tripeptides is desirable because they are more easily adsorbed by the intestinal mucosa than amino acids. In DD-PS 262674 a process for the preparation of phenylalanine-free protein hydrolysates is described in which neither humic substances nor bitter peptides are formed. The chemical part of the process consists of three steps:

1. Five-hour prehydrolysis with 6% phosphoric acid at 50 ° C to 60 ° C,

2. Precipitation of the phosphoric acid as calcium phosphate and its separation,

3. hydrolysis with porcine pancreas, porcine small intestinal mucus and thermitase, duration 10 hours.

Object of the invention

The aim of the invention is to develop a cost-effective process for the preparation of a phenylalanine, bitterpep id- and huminstofffreiem as well as with respect to the other amino acids of full-protein hydrolyzate.

Explanation of the essence of the invention

It is the task to select the protein material and the enzymes so that the aforementioned goal is achieved. In accordance with the invention, freshly precipitated whey protein washed with water and successively washed with water in succession for 5-8 hours with respect to the dry matter are each 5 to 8 hours per pancreatin and pronase at 48 ° C. per 1 to 2% by weight of dry protein and pH = 8 is hydrolyzed, whereby a degradation member 100% · N-NH 2: Ngawmt = 60% is achieved. After enzyme deactivation, the solution is removed four times with charcoal to remove the phenylalanine and then spray dried.

Ausführungsbelsplel

150g by heat denaturation freshly precipitated, washed with water largely lactose, salt and fat-free washed whey protein with 20% = 30g dry matter are suspended in 250ml of water. The liquid is heated with stirring to 48 ° C, adjusted with sodium hydroxide to pH = 8 and treated with 0.6 g pancreatin. While stirring, the temperature and pH are kept constant. After 8 hours, 0.6 g pronase is added. After a further 8 hours, the liquid is heated to 95 ^° C. for deactivation, left at this temperature for 1 minute and cooled to room temperature. It is then stirred four times with ⁶ g of activated charcoal Norit supra special ⁹ each va hour

 The resulting phenylalanine-free hydrolyzate solution is evaporated by spray drying.

Claims (2)

1. Phenylalanine-free protein hydrolyzate, wekhes is free of humic substances and Bitterpeptiden, characterized in that it is obtained in such a way that by heat denaturation freshly precipitated and washed with water whey protein in 5 to 10% aqueous slurry with-based on dry protein-1 to 2Ma .-% pancreatin at 48 ° C and pH = 8 in 5 to 8 hours, then hydrolyzed with pronase under otherwise identical conditions to an amino acid oligopeptide mixture having a degree of degradation of 60% and then freed by treating with activated carbon of phenylalan tin , 2. A process for the preparation of a phenylalanine-free protein hydrolyzate, which is free of humic substances and bitter peptides, characterized in that freshly precipitated by Hitzodenaturisierung and washed with water whey protein in 5 to 10% aqueous slurry with respect to dry protein 1 to 2 Ma. -% pancreatin at 48 ⁰ C and pH = 8 in 5 to 8 hours, then hydrolyzed with pronase under otherwise identical conditions in an amino acid-oligopeptide mixture m nem degree of degradation of 60% and is then liberated by treatment with activated carbon of phenylalanine.