This study aimed to evaluate the potential use of Thai rice for the production of prebiotic isomalto-oligosaccharides through fungal fermentation. Solid-state fermentations of two rice varieties, waxy rice RD6 and non...This study aimed to evaluate the potential use of Thai rice for the production of prebiotic isomalto-oligosaccharides through fungal fermentation. Solid-state fermentations of two rice varieties, waxy rice RD6 and non-waxy rice KDM 105 with Aspergillus oryzae TISTR 3108 were compared. The effects of the main parameters such as incubation time, temperature, pH, fungal spore inoculum size and moisture content were also studied individually to maximise the isomalto-oligosaccharides yield. Results showed that the maximum values of amylolytic activity and total reducing sugar were observed when using rice in SSF with initial moisture content of 70% and inoculated with the inoculum size of 107 spores/g. The optimal conditions of SSF were performed at initial pH 6 and 30 ~C for 5 d. SSF of waxy rice RD6 with Aspergillus oryzae produced highest concentrations of isomalto-oligosaccharides which consisted of isomaltose, panose and isomaltotriose. After fermentation, mashing was used to further hydrolyse the remaining starch in rice slurry. The subsequent rice syrup contained high amounts of isomaltose, panose and isomaltotriose with the values of 44, 10 and 7 g/L respectively.展开更多
文摘This study aimed to evaluate the potential use of Thai rice for the production of prebiotic isomalto-oligosaccharides through fungal fermentation. Solid-state fermentations of two rice varieties, waxy rice RD6 and non-waxy rice KDM 105 with Aspergillus oryzae TISTR 3108 were compared. The effects of the main parameters such as incubation time, temperature, pH, fungal spore inoculum size and moisture content were also studied individually to maximise the isomalto-oligosaccharides yield. Results showed that the maximum values of amylolytic activity and total reducing sugar were observed when using rice in SSF with initial moisture content of 70% and inoculated with the inoculum size of 107 spores/g. The optimal conditions of SSF were performed at initial pH 6 and 30 ~C for 5 d. SSF of waxy rice RD6 with Aspergillus oryzae produced highest concentrations of isomalto-oligosaccharides which consisted of isomaltose, panose and isomaltotriose. After fermentation, mashing was used to further hydrolyse the remaining starch in rice slurry. The subsequent rice syrup contained high amounts of isomaltose, panose and isomaltotriose with the values of 44, 10 and 7 g/L respectively.
