Abstract
•Lipid extraction of fish roe was evaluated after hydrolysis with HT, FP-II and Alcalase proteases.•Alcalase hydrolysis of fish roe protein was more extensive than that of HT and FP-II.•The highest total lipid yield was obtained following hydrolysis of fish roe with Alcalase.•Alcalase hydrolysis achieved the greatest degree of hydrolysis and yielded less oxidised lipid.•The yield of omega-3 fatty acids and phospholipids was highest after HT hydrolysis.
The present study investigated the hydrolysis of protein in hoki roe homogenate using a HT (bacterial), a FP-II (fungal) protease preparations and Alcalase (bacterial) to enhance lipid yield extraction. The degree of hydrolysis was determined at various pH, temperature and time using casein and hoki roe. Total lipid extraction and lipidomic analysis was carried out following proteolysis of hoki roe homogenate. The degree of hydrolysis and SDS-PAGE revealed that the hydrolytic capability of Alcalase was better than HT and FPII. The total extracted lipid yield was better following hydrolysis with Alcalase (19.29 %), compared to HT (18.29 %) and FPII (18.33 %). However, the total phospholipid (PL) and n-3 fatty acid yields were better from HT hydrolysed hoki roe homogenate (PL = 30.7 μmol/g; n-3 = 10.5 %), compared to Alcalase (PL = 22 μmol/g; n-3 = 5.95 %). Overall, this study indicates that HT protease preparation hydrolysis of fish roe homogenate can both enhance lipid extraction and retain lipid quality.