d-Tagatose was transglycosylated by Bacillus stearothermophilus maltogenic amylase (BSMA), and the physicochemical properties of the transfer products were analyzed. Maltosyl-tagatose was the main product of the transglycosylation reaction using maltotriose as the donor and d-tagatose as the acceptor. Glucosyl-tagatose was produced from maltosyl-tagatose by removal of a glucosyl moiety by glucoamylase. The 13C NMR analysis of glucosyl-tagatose suggested that a linkage was formed between the C-1 carbon of the glucose unit and the C-1 carbon of the tagatose unit, thereby producing 1,1-α-glucosyl- tagatose from the transglycosylation reaction. Hygroscopicity measurements showed that glucosyl-tagatose had greater water sorption than did tagatose or sucrose. The glass transition temperature of glucosyl-tagatose was -29°C, which is considerably higher than that of tagatose, -45°C. Its structure and physicochemical properties suggest that glucosyl-tagatose has potential as a low-calorie sweetener and cryostabilizer.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry