Isomalto-oligosaccharides production from rice flour and cassava starch

Abstract

This research aimed to evaluate the use of enzyme technology for the production of
functional isomalto-oligosaccharides (IMO) from rice flour and cassava starch. Three different
samples of non-glutinous rice flour, glutinous rice flour and cassava starch were compared to
produce IMO syrup through the enzyme hydrolysis process. The first step was liquefaction
of starch using α-amylase. The second step was saccharification using β-amylase and pullulanase to accumulate maltose. The last step was transglycosylation using transglucosidase to convert maltose to IMO. 25% (w/v) sample slurries were processed using 5-litre fermenters.
The production process was maintained with appropriate conditions to obtain the maximum
yield of IMO. Liquid samples were taken during bioconversion process to measure sugar and
oligosaccharide concentration. Results showed that the highest concentration of IMO was
obtained from non-glutinous rice flour with the value of 169.1 g/l (isomaltose = 78.2 g/l,
isomaltotriose = 38.7 g/l and panose = 52.1 g/l) at the transglycosylation time of 1 h.
However, using glutinous rice flour to produce IMO could produce IMO up to 106.4 g/l
followed by cassava starch (IMO = 97.9 g/l). These results could indicate that non-glutinous
rice flour was the best raw material among 3 samples to produce IMO.