44D-17 |
Millets malt and worts properties: Germinated at different times and temperatures |
J. K. MUORIA, BC 600, Coors Brewing Co., PO Box 4030, Golden, CO 80401 and P. J. Bechtel, School of Fisheries & Ocean Sciences, Univ. of Alaska, 245 O'Neil Bldg., Fairbanks, AK 99775. In Africa and other areas of the world Millets are used to produce brewers malt. The objective was to evaluate and document the properties of malts and worts made from three varieties of millets. USA millets pearl millet (Pennisetum glaucum), Kenyan pearl millet(Pennisetum glaucum) and Kenyan finger millet (Eleusine coracana) were germinated at 14°C, 18°C and 22°C for 2, 4 or 6 days; dried at 55°C for 18 hours and worts were made. Wort filtration, pH, extract in °Plato, hot water extract, viscosity, malt nitrogen, soluble nitrogen and wort turbidity were determined. Means compared (p<0.05) using a 3*3*3 Proc Glm SAS analysis. The grain protein content was 15.75, 12.94 and 7.84% DM for USA pearl, Kenyan pearl and Kenya Finger millet respectively, all significantly different (p<0.05). Carbohydrate contents (56.41 to 68.83% DM) were all significantly different. Extract in degrees Plato increased as germination days and temperature increased (p<0.05). Kolbach Index increased with germination days and was over 40% for the Kenyan millets at 18 and 22°C and more than 4 days of germination. USA pearl millet had nitrogen values of up to 2.57% and that could cause beer haze formation. Kenyan finger millet at two day 14°C and two and four day USA pearl at 22°C had unacceptable viscosity values of > 1.45 cP. Wort pH decreased from day 2 to 4, and decreased as the temperature increased from 14°C to 22°C. Wort turbidity (NTU's) and wort filtration time did not significantly change with germination time, temperature or varieties. Better worts were produced from malt made at 18°C and 22°C for 4 or more days. The study also shows that the millet variety influenced malt and wort quality characteristics.
Session 44D, International
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