It has been shown that cassava starch can be converted into alcohol most efficiently when fungal enzyme preparations from submerged cultures are used to hydrolyze the starch into sugar. The use of barley malt in the process for conversion of cassava starch has resulted in alcohol yields of 70-74% of the theoretical. Cassava mashes converted by submerged fungal cultures (Aspergillus niger van Tieghem, strain NRRL-337) resulted in alcohol yields up to 90% of the theoretical. Substitutes for the distillers'dried solubles-corn medium were tried. Screened cotton seed meal and soybean meal proved to be a satisfactory substitute for distillers'dried solubles. Dehydrated cassava meal was effectively used in place of corn meal. A comparative study was carried out using several molds from the Collection of the Instituto Agronomico for the purpose of determining their enzyme activity. The mold that presented the highest enzyme potency was found to be the strain of Aspergillus oryzae (Ahlburg) Cohn strain F-27 which had been originally isolated from sake (rice wine). Studies of the dehydrated residues (7% moisture) from hydrolized and fermented mash were found to contain approximately 25% protein indicating their possible value in animal feeds. Simple substrates can be used for the propagation of the mold which is a very efficient conversion agent. It is, indeed, the best saccharifying agent for the countries where a good malt is not available at a low price.
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