Roe protein hydrolysates were prepared from protein isolate recovered via isoelectric solubilization/precipitation of yellowfin tuna Thunnus albacares roe using proteases. Their bioactivity and functional properties were investigated.
The hydrolysate ...
Roe protein hydrolysates were prepared from protein isolate recovered via isoelectric solubilization/precipitation of yellowfin tuna Thunnus albacares roe using proteases. Their bioactivity and functional properties were investigated.
The hydrolysate with the highest free and releasable amino acid content, obtained via enzymatic hydrolysis, was flavourzyme (4,395.1 mg/100 g-RPI), followed by pantidase NP-2 (3,592.8 mg/100 g-RPI), which was significantly higher than the other enzymatic hydrolysates (285.8–739.3 mg/100 g-RPI). The foaming capacity (154–218%) and foam stability of papain, chymotrypsin and bromelain hydrolysates were significantly better than those (100–135%) of other hydrolysates. Similarly, the emulsifying activity index of papain (58.8 m2/g) and bromelain (27.6 m2/g) hydrolysates were superior to other hydrolysates (3.7–10.3 m2/g). Only the ABTS+ [2,2'-Azino-bis(3-ethylbenzothiazoline- 6-sulfonic acid) diammouium salt] radical scavenging activity (IC50, μg/mL) of flavourzyme (82.4 μg/mL) was superior to that of the control (82.9 μg/mL). However, the hydrolysate content (except trypsin hydrolysate) exhibited superior ABTS+ radical scavenging activity compared to the control. The hydrolysates that demonstrated superior tyrosinase inhibitory activity compared to that of the control (1.4%) were flavourzyme (21.8%), aroase AP-10 (21.8%), and protamex (16.7%). Moreover, the angiotensin I-converting enzyme inhibitory activities of all enzyme hydrolysates (51.3–84.1%) were stronger than those of the control (35.7%).