Effect of oxidised phenolic compounds on the gel property of mackerel (Rastrelliger kanagurta) surimi

The effects of different oxidised phenolic compounds (ferulic acid, OFA; tannic acid, OTA; catechin, OCT and caffeic acid, OCF) at different levels (0-0.60% of protein content) on the properties of gels from mackerel (Rastrelliger kanagurta) surimi were investigated. Gels with addition of 0.40% OFA, 0.50% OTA, 0.50% OCF or 0.10% OCT had increases in breaking force by 45%, 115%, 46.1% and 70.3% and in deformation by 12.2, 27.5, 28.1 and 28.4%, respectively, compared with the control (without addition of oxidised phenolics). Lowered expressible moisture content without any change in the whiteness of resulting gels was found. Slightly lower myosin heavy chain (MHC) band intensity of gels added with oxidised phenolics at the optimal level was noticeable compared with that of the control. A sensory evaluation study indicated that addition of oxidised phenolic compounds had no negative impact on the colour and taste of the resulting gels (P > 0.05). Gels with addition of all oxidised phenolics had a finer matrix with smaller strands.