Effects of squid ink as edible coating on squid sp. (Loligo duvauceli) spoilage during chilled storage

Abstract

The effects of squid ink at concentration of 0.10 and 0.25% on the total bacteria count and chemical spoilage indicator; total volatile basis nitrogen (TVBN) and trimethylamine (TMA) of squid (Loligo duvauceli) were analysed. The analysis were performed at interval of 5 days during 15 days of chilled storage (4°C). This studies also investigate the antioxidant capacity of the squid ink. The melanin-free squid ink were subjected to ferric reducing power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) analysis. The FRAP values found in squid ink were 0.04±0.01 μmole TE g-1 meanwhile DPPH values were recorded at 0.81±0.00 μmole TE g-1. The squid ink at both 0.10 and 0.25% concentration showed a significantly (p<0.05) reduced amount of microflora in squid during 15 days of storage compared to the amount of microflora found in untreated samples. After 15 days of storage, squid coated with 0.25% squid ink showed a significantly (p<0.05) lower accumulation of TVBN compared to other treatments. A similar trend were found for TMA value. During 15 days of storage, the controls showed a significantly (p<0.05) higher accumulation of TMA compared to squid coated with 0.25% of squid ink. By using TMA analysis, squid coated with 0.25% squid ink were estimated to prolong their shelflife for up to 9 days in chilled condition compared to untreated squid, which can stand only for 5 days. Therefore, pre-treatment with squid ink coating upon chilled storage are beneficial on keeping the quality and a potential practice for post-harvest industry