Optimization of Ultrasound and Microbubble-Assisted Maillard Reaction on Conjugated Cricket Protein with Fructooligosaccharide

The traditional wet-heating Maillard reaction (MR) used a long-duration process and affected the over-browning color of the product. Thus, ultrasound (UL) and microbubbles (MB) were studied to assist the traditional MR on cricket protein isolated (CPI) conjugated with fructooligosaccharide (FOS) called CPF. These processes were carried out using central composite design (CCD). Two independent variables were UL (2–58 min) and MB times (6–35 min). The significant variables WS, OHC, EAI and ESI, DPPH, ABTS, and FRAP were further optimized by the response surface method (RSM). RSM results showed that the quadratic model can predict response values. The optimal conditions yielded the most favorable functional properties (WS = 89.38 g/L, OHC = 8.65%, EAI = 81.37 m 2 /g, and ESI = 120.75 min) as well as the highest antioxidant activity (DPPH = 14.77, ABTS = 14.55, and FRAP = 13.98 µmol TE/g). Moreover, the UL and MB were not significantly affected by the browning index of CPF. This study can conclude that the UL and MB-assisted MR process is a promising method to decrease the processing time and is highly effective at improving the characteristics, functional properties, and antioxidant activity of conjugated cricket protein.