Effectiveness of Toothpony (Gazza minuta) protein hydrolysate on reducing oil uptake upon deep-frying

Abstract

Toothpony (Gazza minuta) is not typically used for human consumption due to its small size and low meat content, which is widely used as a fish meal. It is stated to be high in protein content and may be suitable for fish protein hydrolysate (FPH) production. Deep-fat fried foods contain significant amounts of fat, in some cases up to one-third of the total food weight after frying. Toothpony FPH with low oil-binding ability may reduce the amount of oil consumed by deep-fried products. The objective of this research was to measure the physicochemical properties of Toothpony FPH and its utilisation in reducing the oil intake of deep-fried food. Toothpony FPH was obtained using the enzymatic method successfully. Batter formulations are prepared by adding 0%, 2%, 4%, 6% and 8% of Toothpony FPH into the sample mixtures. The present study indicates the degree of hydrolysis of Toothpony FPH determined by trichloroacetic acid (TCA) method was found to be 98.02%. Toothpony FPH's molecular weight distributions ranged from 7 to 175kDa and FTIR's transmission spectrum indicated the presence of amide I and amide II compounds (1654 and 1535cm-1). Oil binding capacity of Toothpony FPH was found to be low, which was 1.9 g oil/ g protein. This study indicated that 4% of Toothpony FPH produced the optimum amount to be incorporated in batter in order to best reduce oil uptake. In sensory evaluation, deep-fat-fried squid incorporated with 8% of Toothpony FPH showed the highest acceptance in all attributes, which were colour, crispness, oiliness, taste and overall acceptability. This approach offers the potentials use of Toothpony fish FPH for the production batter formulation which is efficient in the reduction of oil uptake.