Authors : Daniella Cristine Fialho Lopes , Carolina Schaper Bizzotto , Raquel Linhares Carreira , Wendel de Oliveira Afonso , Carlos de Oliveira Lopes Jr and Marialice Pinto Coelho Silvestre
Abstract: Aiming the preparation of low-phenylalanine protein hydrolysates from rice, 2 pancreatins were used for the hydrolytic process and the activated carbon was used as adsorbent. Second derivative spectrophotometry was used to evaluate the efficiency of Phenylalanine (Phe) removal. Also, the peptide profiles of the protein hydrolysates were analysed. Initially, rice proteins were extracted by an alkaline process, varying the pH (9.0, 10.0 or 12.0), the stirring time (15 or 60 min) and the velocity of centrifugation (106, 425 or 2,660�g). Then, 12 protein hydrolysates were prepared using 2 different Enzyme: Substrate (E:S) ratios (1 and 2%) and Rice Protein Extract (REP) concentrations (1-3 g/100 mL). The protein content of extracts changed from 19.63-77.92% and the highest extraction yield (84.74%) was obtained at pH 12.0, after stirring for 60 min and centrifuging at 425�g. The Phe removal was similar for both pancreatins, varying from 72-100% and giving final Phe contents from 0.28-95 mg/100 g of product. For pancreatin 1, the best results were obtained with REP concentration of 3% and E:S of 2%, while for pancreatin 2 REP concentrations as well as E:S of 1 and 2% produced the smallest Phe content. The peptide profile obtained with pancreatin 2 was more advantageous than pancreatin 1, since it produced much smaller large peptide and little higher oligopeptide contents.
Daniella Cristine Fialho Lopes , Carolina Schaper Bizzotto , Raquel Linhares Carreira , Wendel de Oliveira Afonso , Carlos de Oliveira Lopes Jr and Marialice Pinto Coelho Silvestre , 2008. Removal of Phenylalanine from Protein Hydrolysates Prepared with Rice . Journal of Food Technology, 6: 57-65.