Optimization of debittering of soybean antioxidant hydrolysates with β-cyclodextrins using response surface methodology.

Antioxidant hydrolysates from soybean have the potential as the new antioxidants, but the bitterness limites their application. A study on the debittering of the soybean antioxidant hydrolysates with β-cyclodextrins and the effects of the debittering conditions on the reducing power of the peptides was conducted using response surface methodology (RSM). The coefficient of determination, R (2) values for bitterness and reducing power were 0.883 and 0.902 respectively. Reducing power of the soybean hydrolysates varied curvilinearly with increase of temperature, mass fraction of β-cyclodextrin, and incubation time. The optimum conditions to obtain the hydrolysates with the minimum bitterness and the maximum reducing power were: temperature 38.50 °C, the mass fraction of β-cyclodextrin 2.00%, and incubation time 12 min, The resulting response functions under this conditions were the reducing power (OD700 nm) of 0.453 and bitterness of 0.290, which was under the threshold for the detection of bitterness taste.