Improving quality of smoked sardine fillets by soaking in cuttlefish ink

Abstract

Cuttlefish ink, a by-product of food processing, is a promising source of natural compounds with antioxidant and antimicrobial activities and it can be used as a natural additive for sea food products. Therefore, this work aimed to extend the shelf life of smoked sardine by soaking in cuttlefish ink solution. No antibacterial activity of cuttlefish ink solution with different concentrations (1%, 2% and 3%) has been determined against Staphylococcus aureus, Listeria monocytogenes and Pseudomonas aeruginosa. DPPH radical scavenging activity for the ink samples ranged from 91% to 95% for the three ink solutions. Fresh fillets were steamed, smoked and soaked in the three ink solutions and then stored at 4 °C for 35 days. During storage, total viable counts, total volatile basic nitrogen values and peroxide values increased significantly only for control samples and those soaked with 1% of ink solution. Soaked samples showed the lowest amount of histamine when compared to the control one which may be related to a better controlled microbial proliferation. Ink solutions did not affect the whiteness of fillets, whereas the hardness increased significantly during the two first weeks of storage. Obtained results support using cuttlefish ink to lengthen smoked sardine shelf life.

Keywords:
Sepia ink; antioxidant activity; antimicrobial activity; Sardinella aurita, stability