33A-6 |
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A. TREJO-GONZÁLEZ1, V. Maravelez, C. Gómez-Aldapa, M. Zamora-Díaz, and M. Cantwell. (1) Dept. Bioprocesses, UPIBI-IPN, Av. Acueducto de Guadalupe, Col. La Laguna-Ticomán, Mexico City, 07340, Mexico We have previously shown that chemical gelatinization of starch occurs in corn grains when they are soaked for long periods in saturated lime solutions, and that the grains are subsequently capable of rapid germination. In this study we explored whether, in barley grains subjected to the same steeping conditions, there would be an acceleration of biochemical changes for the production of malt. The main objective was to observe the effect that steeping in lime solutions had on the germination of barley. Barley grains cv Esmeralda six-row were steeped in saturated solutions of lime from 0 to 2 % (w/w) at ambient temperature (18-23C) for periods up to 72 h. After treatment, the grains were washed with water and placed in a germination cabinet at 20 ± 2C and 90% RH for up to 96 h to germinate. Activity of a-amylase (U/mg protein), sprout length (cm), seed viability (tetrazolium test) were determined. Steeped and germinated barley grains were also observed under scanning electron microscopy. There was a very rapid uptake of lime solution by the barley grains during the first 30 hours of treatment. The barley grains were 98% viable after all periods of steeping. Grains soaked 24 h and germinated 70 h had the highest activity of a-amylase, longest sprout length and highest % germination. Under SEM, chemical gelatinization of starch grains was observed in barley sections after different steeping treatments, and starch breakdown was observed in grains during germination. No fungal growth was observed during germination after the steeping treatments. These results demonstrate that steeping in lime solutions shortened the period required for malt production.
Session 33A, Carbohydrate: General
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