HYDROTHERMAL TREATMENT OF STARCH IN PRESE NCE OF ALPHA-AMYLASE .1. HYDROLYSIS OF STARCH WITH ALPHA-AMYLASE IN HETEROGENEOUS PHASE

The hydrolysis of wheat-, rye- and potato starch with alpha-amylase fr om Thermoactinomyces vulgaris in heterogeneous phase yields a hydrolys ate with a high content of maltose (50% maltose, 15-20% maltotriose) b y using a stepwise increase of temperature. The yields are up to 85% r elated to the amount of original starch. In the non hydrolysed residue the granular shape of starch is maintained as long as the reaction te mperature is below 64-degrees-C (wheat and rye) or 70-degrees-C (potat o). The residual starch is the product of a hydrothermal treatment res ulting in an increase of swelling temperature. The lipid remains in th e non-hydrolysed residue whereas proteins are dissolved simultaneously with the hydrolysed starch.