Chemical Characterization of Hydrolyzed Protein Meal Obtained from Trout (Oncorynchus My kiss) By-products Silage

Abstract

Objective: To assess conditions of yielding and chemical characterization of hydrolyzed protein meal obtained from chemical silage of trout by-products. Methods: Trout by-products chemical silage was obtained by adding formic acid. Hydrolysis, pH and acidity were tracked to define the extraction day of the hydrolyzed protein meal. This hydrolyzed meal was characterized by determining soluble and volatile nitrogen, peroxide value, molecular mass profile, amino acids profile, lactic and formic acid concentration and digestibility with pepsin; and it was compared with a commercial fish meal. Findings: Resulting by-products of rainbow trout showed a lipids and protein level close to 90% in dry matter, which makes them a viable exploitation alternative. Degree of hydrolysis obtained was close to 62%, obtaining molecular masses of protein fractions between 0.2 and 0.6 KDA, condition that made easier the extraction of the lipid fraction and obtaining a fat-free hydrolyzed protein meal by endogenous enzymatic hydrolysis, with a chemical compositions that allows its use as raw material or additive in formulation for animal diet, complying with the requirements of fish meal legislation. Pepsin digestibility test showed a superior digestibility compared with commercial fish meal, which creates and advantage in relation to absorption and nutritional exploitation. Novelty/Improvement: A product with technical-functional features in relation to its nutritional advantages and chemical composition, was obtained, which can represent differentiation to advance in innovation in animal food and nutrition. Keywords: Digestibility, Fish Meal, Hydrolyzed Protein, Silage, Trout