Functional properties of rainbow trout (Oncorhynchus mykiss) viscera protein hydrolysates

This study analyzes the effect of degree of hydrolysis (DH) and pH of protein hydrolysates from rainbow trout (Oncorhynchus mykiss) viscera on their functional properties such as solubility, emulsifying and foaming properties. Additionally, the enzymatic hydrolysis of rainbow trout viscera with Alcalase (R) 2.4L was optimized. The Response Surface Methodology (RSM) was used to assess the effect of substrate concentration (S), enzyme concentration (E), temperature (T), fat concentration (F), and agitation speed (v) on DH. The study found that the highest DH of 20.48 +/- 1.07% was attained under the optimum conditions, including S of 54.5 g of protein/L, E of 0.72 UA/g protein, F of 5.09% (w/w), v of 102 rpm, pH 8.5 and T of 60 degrees C, during a reaction time of 6 h. The results show that the functionalities of the hydrolysates were affected by both DH and pH. The hydrolysate with DH 20% at pH 7 exhibited the highest solubility. The emulsifying and foaming properties of hydrolysates reached their highest values at DH 5%. Concerning the effect of pH, the study found that all functional properties at different DHs had the lowest values at pH 4.0. Therefore, the study results suggest that protein hydrolysates of rainbow trout viscera could have potential uses as functional ingredients in food.

Automated summary

This study analyzed the impact of degree of hydrolysis (DH) and pH on the functional properties of protein hydrolysates from rainbow trout viscera. The results showed that both DH and pH influenced the solubility, emulsifying, and foaming properties of the hydrolysates. Optimal conditions were identified to achieve the highest DH. The study suggests that these protein hydrolysates could be used as functional ingredients in food.