A Systematic Approach to the Comparison of Cost Efficiency of Endopeptidases for the Hydrolysis of Atlantic Salmon (Salmo salar) By-Products

• Published in: Food Technology and Biotechnology
• Main Authors: Tone Aspevik, Henning Egede-Nissen, Åge Oterhals
• Format: Article in Journal/Newspaper
• Language: English
• Published: University of Zagreb Faculty of Food Technology and Biotechnology 2016
• Subjects: endopeptidase; fish protein hydrolysate; degree of hydrolysis; pH-STAT; protein recovery; cost efficiency; Biotechnology; TP248.13-248.65; Food processing and manufacture; TP368-456; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.17113/ftb.54.04.16.4553; https://doaj.org/article/ba14fdbf4a9e40f4941edd220df32b74

The hydrolytic and cost efficiencies of five endopeptidases (Alcalase 2.4L, Corolase 7089, Neutrase 0.8L, Promod 671L and Protex 7L) to hydrolyze Atlantic salmon by-products were compared at standardized activity levels based on a casein assay. The substrate was characterized prior to the hydrolytic experiments (pH=6.5, t=50 °C) to obtain substrate-specifi c constants for nitrogen to protein mass (in g) ratio, i.e. conversion factor fN=5.23 and total amount of peptide bonds htot=9.3 mmol per g of protein. At low enzyme activity to substrate ratio, all enzymes were equally effi cient in hydrolyzing the substrate. At highest enzyme activity to substrate ratio, Protex 7L, Alcalase 2.4L and Promod 671L gave higher degree of hydrolysis (DH=14.2–14.6 %) than Corolase 7089 (13.2 %) and Neutrase 0.8L (11.6 %) after 120 min of hydrolysis. No differences were observed in protein recovery (yield of solubilized protein) relative to DH. Determination of DH was followed by the pH-STAT and o-phthaldialdehyde methods. Based on pH-STAT data, response surface regression models were established based on the combined eff ects of hydrolysis time and enzyme activity to substrate ratio on DH and protein recovery. The modelling approach was combined with enzyme cost to identify the most cost-efficient enzyme (Protex 7L).