Detanning of Deoiled (Shorea robusta) Seed Meal by Continuous Extraction with Water during Centrifugation

Continuous washing of deoiled sal seed meal (DSSM) is carried out in a basket centrifuge of 130 mm diameter and 60 mm height. Tannin extractability and extent of tannin reduction from DSSM, are studied at different water to cake ratios. With water to cake ratio of about 50 l/kg., 45 to 55 per cent of tannin present in DSSM, is extracted. Further washing with water results in additional tannin extraction or 25 per cent, making the total extractability of 75 to 80 per cent. Tannin content In DSSM is reduced from 13.7 per cent to below 8 per cent at water to cake ratios of about 50 l/kg during initial extraction, while subsequent washing results in further reduction upto 4 per cent.