Treatment of Sorghum Grains with Calcium Hydroxide for Calcium Enrichment

Abstract

Four varieties of sorghum grain (SB-1079, DSH-1, CSH-5, and SB-905) were subjected to four methods of treatment with saturated calcium hydroxide solution (soaking and drying with and without washing for germinated and ungerminated grains) for five different periods: dipping only, or 4, 8, 16, or 32 hours of soaking. Among all the varieties, treated germinated grain showed a higher calcium content than treated ungerminated grain. Irrespective of the method or duration of soaking, SB-905 showed a significantly lower calcium content than the other varieties. A maximum calcium content of 253.6 mg per 100 g of grain was obtained in the DSH-1 variety when germinated grain was soaked and dried, compared to a 55.0 mg per 100 g in the untreated sample. Washing after soaking resulted in a decreased calcium content in both germinated and ungerminated grains. Increasing the soaking time from simple dipping to four or eight hours resulted in a significant increase in calcium content. Further increases in soaking time to 16 or 32 hours caused a significant reduction in calcium content.