Preparation and scalin up of a low phenylalanine enzymatic hydrolysate of bovine whey proteins

RESUMO

We describe the preparation of pancreatic enzymes hydrolysate of milk whey proteins containing low levels of aromatic amino acids. Pancreatin and trypsin/chymotrypsin (6.3 percent w/w protein) when used to hydrolyze whey proteins for 27 h at 37±2 °C, released 74 percent of the Phe, 100 percent of the Tyr and 100 percent of the Trp as free amino acids. Most of the free aromatic amino acids present in 2 kg hydrolysate were separated from the remaining peptides and other amino acids by gel filtration on a 15 liter Sephadex G-25 column eluted with 5 percent acetic acid at 60 liters 'h POT. -1' 25°C. The product, recovered in 37 percent yield, contained 0.70 mmol Phe, 0.41 mmol Tyr, and <0.01mmol Trp/100mmol recovered amino acids. The hydrolysate had a general amino acid composition similar to the whey proteins from which it was prepared and could be use as a nitrogen source for patients with phenylketonuria or tyrosinemia after the addition of appropriate aromatic amino acids...