Effects of dietary scallop and squid hydrolysates on growth of European seabass, Dicentrarchus labrax; California yellowtail, Seriola lalandi; and barramundi, Lates calcarifer

Abstract

Squid processing byproducts and scallop viscera were homogenized and subjected to hydrolysis at 55°C for 1.5 hr, followed by pasteurization at 75°C for 30 min. The respective hydrolysates were incorporated into diets in which 30–70% of fishmeal (FM) was replaced with soybean meal (SBM) and evaluated as is (wet), dried, or impregnated into SBM for their effects on growth of European seabass, Dicentrarchus labrax; California yellowtail, Seriola lalandi; and barramundi, Lates calcarifer, in a series of 8‐week experiments. No adverse thermal deterioration in the quality of hydrolysate occurred because of drum drying, compared to the wet hydrolysate. No differences were observed in growth of California yellowtail between SBM mixed with dry hydrolysate and SBM impregnated with wet hydrolysate. Dietary inclusion of hydrolysate improved feed attractability and growth and was beneficial in the early juvenile stage but not in the growout stage for European seabass and California yellowtail. However, in barramundi, no discernable benefit was observed from the addition of hydrolysates. The improved feed attractability and growth appear to be dependent on species and type of hydrolysate. The texture of fillets of yellowtail fed 70% FM replacement with SBM + squid hydrolysate diets was significantly firmer than without squid hydrolysate.

Squid industry by-product hydrolysate supplementation enhances growth performance of Penaeus monodon fed plant protein-based diets without fish meal

“…Given the present results of the proximate composition of the squid by-product hydrolysate, it is evident that enzymatic hydrolysis has improved the protein content of squid byproducts. This value is much higher than squid by-product hydrolysate's previously reported protein content (Lian et al, 2005;Choi et al, 2014;González-Félix et al, 2014;Lee et al, 2018). Similar to the degree of hydrolysis, these differences in the proximate composition of the hydrolysate produced in the present study in comparison with the previous results might be due to the squid species used, degree of hydrolysis, hydrolysis duration, enzyme to substrate ratio, and the enzyme used to hydrolyze the raw materials.…”

“…González-Félix et al (2014) also stated that prolonged duration and higher temperatures greatly improved squid by-product hydrolyzation. Varying degree of hydrolysis has been reported by several authors upon hydrolyzing squid by-products (Choi et al, 2014;González-Félix et al, 2014;Suárez-Jiménez et al, 2015;Lee et al, 2018). These differences might be due to several factors such as the enzyme to substrate ratio, squid species used, hydrolysis conditions, and the squid parts used in the production of hydrolysate.…”