Recovery of protein-rich byproducts from sweet potato stillage following alcohol distillation

Journal Article · Thu Jan 01 04:00:00 EST 1987 · J. Agric. Food Chem.; (United States)

DOI:https://doi.org/10.1021/jf00075a009· OSTI ID:5566080

Wu, Y V; Baghy, M O

Sweet potato can yield 1000 gallons of ethanol/acre compared with 250-300 gal/acre for corn. Sweet potatoes of normal, relatively high, and very high dry-matter contents were fermented to ethanol. Pectinase was necessary to decrease viscosity before fermentation for economic processing, especially for varieties of normal and relatively high dry-matter contents. Attained yield of ethanol was 90% of theoretical value. After ethanol was distilled, residual stillage was separated by screening and centrifugation into filter cake, centrifuged solids, and stillage solubles. Filter cake and centrifuged solids had crude protein contents (nitrogen x 6.25, dry basis) of 22-32% and 42-57%, respectively, and accounted for 44-85% and 0-17% of total sweet potato nitrogen. Sweet potatoes and their fermented products had 4.3-7.6 g of lysine/16 g of N and are expected to have good nutritional value. This practical method to ferment sweet potato for ethanol and to recover valuable protein-rich byproducts may have commercial potential. (Refs. 19).

• Research Organization: U.S. Dept. of Agriculture, Agricultural Research Service, Northern Regional Research Center, Peoria, IL 61604
• OSTI ID: 5566080
• Journal Information: J. Agric. Food Chem.; (United States), Journal Name: J. Agric. Food Chem.; (United States) Vol. 35:3; ISSN JAFCA
• Country of Publication: United States
• Language: English

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ALCOHOLS
AMINO ACIDS
ANIMAL FEEDS
BIOCONVERSION
BIOSYNTHESIS
BLOOD SUBSTITUTES
BY-PRODUCTS
CARBOHYDRATES
CARBOXYLIC ACIDS
CENTRIFUGATION
CEREALS
COMMERCIALIZATION
COMPARATIVE EVALUATIONS
DISTILLATION
DRUGS
ECONOMICS
ELEMENTS
ENZYMES
ETHANOL
FERMENTATION
FILTRATION
FOOD
GRASS
HEMATOLOGIC AGENTS
HYDROXY COMPOUNDS
LYSINE
MAIZE
MOISTURE
NITROGEN
NONMETALS
NUTRITION
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC WASTES
PECTINS
PLANTS
POLYSACCHARIDES
PROTEINS
QUANTITY RATIO
RECOVERY
RESIDUES
SACCHARIDES
SCREENING
SEPARATION PROCESSES
SOLUBILITY
STILLAGE
SYNTHESIS
TUBERS
VISCOSITY
WASTES
YIELDS