Use of Heat Treatments for Saccharification of Sweet Potato Mashes

Abstract

ABSTRACT The absolute and relative levels of major carbohydrate fractions were determined after heat treatment of aqueous slurries of sweet potato roots (mashes). Soluble solids concentration increased in a linear fashion over a temperature range 30–80°C. Mash maltose concentration increased with temperature to 70°C while alcohol‐insoluble solids (AIS) correspondingly decreased, presumably as a result of heat‐induced beta‐amylase activity. Glucose and AIS concentrations increased while maltose decreased as temperature increased from 70°C to 80°C. Duration of temperature maintenance after initial temperature increase had no effect on mash carbohydrate levels. Differences in carbohydrate composition between mashes of two sweet potato genotypes were measured. These results suggested that rapid heating of sweet potato mashes to 80°C may be optimal for starch conversion and handling of sweet potato mashes prepared for ethanolic fermentation.