Effect of osmotic dehydration with binary/ternary sugar solutes on macro-& micro-structure, chromaticity and thermal stability of dehydrated peach slices prepared by heat pump drying

The binary solution (sucrose/erythritol solution) and ternary solution (compound sucrose/erythritol with maltitol/fructooligosaccharide) were prepared as osmotic dehydration (OD) pretreatment before hot-pump-dried (HPD). Based on the analysis of OD solutions, the analysis of quality of dehydrated yellow peach slices (DYPS) were emphasized on the soluble sugar content, macro-&micro-structure and thermal stability. Following with sucrose and maltitol (SM)-OD pretreatment, DYPS showed the decreased free sugar content and improved cohesiveness (0.85 ± 0.01) and springiness (97.92 ± 1.47 mm). Moreover, the highest L* value (71.35 ± 4.39) observed in Erythritol group was related to the sugar layer on the DYPS surface. The biggest b* (44.41 ± 3.63) value was observed in EM group, which was in line with the high content of carotenoids (24.52 ± 1.84 μg/mL). However, no significant differences were observed in total phenol content of DYPS with various pretreatments. The penetration of sucrose compounded with maltitol into DYPS tissue supported the homogeneous and regular cellular arrangement, which improved thermal stability of cell wall polysaccharides. As a whole, SM was expected to be the promising ternary osmotic solution for DYPS.