Effect of modified starch, soybean protein on hardness, weight loss and size shrinkage of protein gel of minced yellowfin (Thunnus Albacares) tuna dark muscle
Abstract
Under effect of heat, the tuna dark muscle becomes loose, increasing of water-loss as well as reducing the size of protein gel of minced dark muscle. This study evaluated the effect of some co-gelators (modified starch (MS) and soybean protein (SPC)) on hardness, weight-loss and size-shrinkage of protein gel after heating. The research results show that there is a significant influence of the co-gelator on the water holding capacity or the size-loss of heat-induced protein gel. The influence of MS is stronger than that of SPC, the water holding capacity can be reduced by about 5 or 6 times and the size-shrinkage is reduced by about 2.6 or 4.5 times with an added rate of MS or SPC of 6%. The hardness of protein gel increased with increasing of added co-gelator. SPC was better than MS on the hardness of protein gel, the hardness can be increased 4.8 times or 1.6 times when adding 6% SPC or MS.
