Incorporation of oligosaccharides in fermented rice cakes: Impact on quality, starch retrogradation, and digestibility.

High sucrose content and rapid staling limit the quality of fermented rice cakes (FRCs). This study evaluated the effects of substituting sucrose with xylooligosaccharides (XOS), fructooligosaccharides (FOS), and galactooligosaccharides (GOS) at different ratios (10%-40%) on the quality, starch retrogradation, and starch digestion properties of FRCs. Results showed that oligosaccharides delayed the pasting of rice flour and reduced its gelatinization enthalpy. Notably, a 20% substitution optimized batter gas retention, increasing specific volume and elasticity while reducing hardness. Moreover, gas chromatography-ion mobility spectrometry revealed that XOS, FOS, and GOS promoted the generation of fermentation metabolites, enriching the flavor profile with fruity ester aromas. During storage, oligosaccharides restricted water migration from bound to free states and retarded both short-range starch rearrangement and long-range crystal growth, effectively delaying hardening. Furthermore, XOS increased resistant starch content in FRCs by approximately 57.8%. These findings suggest that moderate replacement of sucrose with oligosaccharides is a promising strategy for delaying staling and improving the overall quality of FRCs.