Amino acid composition, antioxidant and functional properties of protein hydrolysates from the roe of rainbow trout (Oncorhynchus mykiss)

Abstract

Summary A fish roe protein hydrolysate from rainbow trout (Oncorhynchus mykiss) trout roe protein hydrolysates (TRH) was produced by pepsin and Alcalase. Proximate, amino acid compositions, protein digestibility and molecular mass distribution of the hydrolysates were determined. The degree of hydrolysis was found to be 44.08% and 27.62% (pepsin and Alcalase, respectively). The two hydrolysates contained a high amount of essential amino acids (33.53% Alcalase–29.39% pepsin). The results showed that TRH by different enzymes is a good source of the leucine and lysine amino acids. The pepsin produced a white powder with higher brightness (L* = 89.50). Alcalase hydrolysate was brownish yellow in colour (L* = 52.85, a* = 10.30, b* = 26.25). The hydrolysates represented excellent antioxidant activities in various concentrations. TRHs showed a good foaming and emulsification properties. The results thus revealed that protein hydrolysates from rainbow trout roe could be used as food additives possessing essential amino acids and antioxidant activity.

Valorization of Aquaculture By-Products of Salmonids to Produce Enzymatic Hydrolysates: Process Optimization, Chemical Characterization and Evaluation of Bioactives

“…In all cases, the essential amino acid content was higher (value of TEAA/TAA as percentage) than recommended for human adults and infants [30,31]. Similar percentages to our outcomes were observed for enzymatic hydrolysates of rainbow trout frames and roes generated by Alcalase [14,25], and salmon frames catalyzed with Protamex [3] but inferior when Papain was applied to identical salmon wastes [9]. Nevertheless, the data of TEAA/TAA for salmon viscera hydrolysates [32] were higher than here reported for other by-products of salmonids (46% vs. 33-37%).…”

“…In all reports about the production of salmonid FPHs, the mathematical modeling of proteolytic kinetics was unexplored. Taking into account the published data of H (%) at the end of Alcalase treatment, our values of H m (Table 3) were always higher or slightly higher than those obtained for hydrolysates of salmon head (17%), salmon frames (27%), and trout roe (28%) [9,24,25]. Using soluble proteins extracted by CaCl 2 -citric treatment of a mixture of RT by-products (heads, frames, and viscera) as substrate, the value of H was of 42% for a 3-h Alcalase hydrolysate [26].…”

“…Total lipids (Lip), proteins (Pr-tN, as total nitrogen × 6. 25), and proteins after degreasing samples (Pr-tN *) were determined using dried substrates. Error bars showed the intervals of confidence for n = 3-4 (samples from independent batch) and α = 0.05.…”

“…Nevertheless, S_H led to the significant lowest data of ABTS (2,2 -azinobis-(3-ethyl-benzothiazoline-6-sulphonic acid) and Crocin (p < 0.05). In general, the numerical response of DPPH method, Crocin protocol was never employed to analyze salmonid samples, was not sufficiently attractive when are compared with samples of Alcalase hydrolysates from trout roe [25] and for soluble proteins obtained by chemical solubilization of a mixture of RT by-products [33]. However, enzymatic hydrolysates from pectoral fin and collagen skin of salmon showed similar % of DPPH than those listed in Table 6 [34,35].…”

Production, Characterization, and Bioactivity of Fish Protein Hydrolysates from Aquaculture Turbot (Scophthalmus maximus) Wastes

“…No comparison can be made with literature results since this is the first report dealing with the production of FPHs from turbot from the aquaculture industry. Regarding other fish by-products, our outcomes of H m are in range (similar or slightly lower) with the values observed for hydrolysates from whole fish discards as megrim, blue whiting, red scorpionfish, and grenadier [30], but higher than those obtained for FPHs of boardfish, and pouting and by-products from salmon and trout [6,13,32,33]. In the last decade, Alcalase has shown an excellent capacity to hydrolyze several fish wastes such as salmon by-products [25], yellowfin tuna heads [26], and Atlantic cod, having being also applied to cattle viscera [12,27].…”