Feasibility of enzymatic hydrolysis and alcoholic fermentation of starch contained in buffalo gourd (Cucurbita foetidissima) roots

The suitability of using annually grown, carrot-sized buffalo gourd (Cucurbita foetidissima) roots as a feedstock for alcoholic fermentation was explored. Roots grown in 1982 and 1983 were slurried, dextrinized and saccharified using Takathermtrade mark and Diazymetrade mark (commercial enzymes manufactured by Miles Laboratories), and fermented by the action of Saccharomyces cerevisiae. These processes were monitored in detail and results were compared with those displayed by controls formulated using potato tubers. The preparation of gourd root slurries with suitable viscosity characteristics for enzymatic digestion required the addition of water (at least 50% by weight) which reduced the proportion of fermentable sugars in the resulting saccharified suspensions. The resulting slurries were well-suited to enzymatic conversion of starch to sugar. Estimates of enzymatic efficiency in gourd root suspensions did not suggest the presence of naturally occurring amylase or glucosidase inhibitors in these plant materials. Saccharified gourd root mashes supported yeast growth well and produced ethanol yields at 82.2-86.5% of the theoretically maximum efficiency.