Investigating the Effects of Ultrasonication and Roasting on Starch Digestibility and Glycemic Index in Oat‐Based Dairy Analog

ABSTRACT This study optimized the oat‐based dairy analog (OBDA) preparation by ultrasound treatment. For this purpose, ultrasound amplitude (USA; %) and time (UST; min) were taken as independent variables. Meanwhile, yield (%), total soluble solids (TSS), and viscosity (mPas) were chosen as dependent variables. Optimal conditions were identified at 20% USA and 17 min UST, yielding a mass yield of 86.42%, TSS of 7.30°Brix, and viscosity of 10.08 mPas, with a desirability of 90%. Further, comparisons between ultrasonicated (US), roasted, and control samples revealed improved zeta potential (−26 mV) and protein solubility (49.42%) in the US sample. Ultrasound and roasting treatment altered the starch digestibility of the sample, hence the glycemic index (GI). A lower glycemic index was observed in the US (43.31 ± 0.41) than in roasted (49.70 ± 0.26) and control (45.51 ± 0.19) samples with a digestion rate constant ( k ) less than 0.006. However, no alteration in the chemical nature of OBDA was observed in FTIR.