Efficacy of whey protein coating incorporated with lactoperoxidase and α-tocopherol in shelf life extension of Pike-Perch fillets during refrigeration

- Lactoperoxidase (LPOS) and α-tocopherol were incorporated to whey protein coating.
- Antibacterial activity against several bacteria was observed in Pike-Perch fillets.
- Chemical spoilage indexes (TBA, TVB-N and pH) were well controlled.
- In some cases LPOS and α-tocopherol had a mutual antagonistic effect in both cases.
- Possible interaction between LPOS and α-tocopherol will be needed more studies.

Efficacy of whey protein coating solution (WPS) incorporated with lactoperoxidase system (LPOS, 2.5%) and α-tocopherol (1.5% and 3%) on the shelf life of Pike-Perch fillets during refrigeration storage (4 °C) was studied. Treated batches with α-tocopherol showed lower changes in color, odor, and TBA (Thiobarbituric Acid) compared with WPS batches (P < 0.05). WPS+2.5% LPOS treatment exhibited better quality about bacterial load, TVB-N (Total volatile basic nitrogen), texture, and overall acceptability compared to WPS (P < 0.05), while color, odor, and TBA were not significantly affected by LPOS (P > 0.05). Although interaction between LPOS and α-tocopherol in some cases led to the mutual antagonistic effect in both cases, WPS+2.5% LPOS+1.5% α-tocopherol and WPS+2.5% LPOS +3% α-tocopherol treatments had higher qualities than other treatments. Thus, it can be concluded that the combination of LPOS and α-tocopherol can donate antibacterial and antioxidant properties to WPS, and could have a high potential to be applied in the shelf life extension of Pike-Perch fillets during cold storage.