Abstract
The diastatic activity of three sweet potato varieties was principally due to \-amylase. Substitution of sorghum malt with sweet potato at 20% (w/v) gave a higher activity than an all-sorghum malt. Maltose in the sorghum/potato wort was 50 mg/ml, similar to that in barley malt. The free alpha amino nitrogen of the sorghum/potato worts was lower than that of the all-sorghum malt but was still within the range needed for yeast growth. Incubation of the potato enzymic extract with isolated sorghum endosperm cell walls and viscosity tests demonstrated the presence of (1→3, 1→4)-β-glucanase (limiting in sorghum) in the sweet potato.
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Etim, M.U., EtokAkpan, O.U. Sorghum brewing using sweet potato enzymic flour to increase saccharification. World J Microbiol Biotechnol 8, 509–511 (1992). https://doi.org/10.1007/BF01201950
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DOI: https://doi.org/10.1007/BF01201950