Cereal Chem 64:39-41   |  VIEW ARTICLE

Cereal Pentosans: Their Estimation and Significance. III. Pentosans in Abraded Grains and Milling By-Products.

S. Hashimoto, M. D. Shogren, L. C. Bolte, and Y. Pomeranz. Copyright 1987 by the American Association of Cereal Chemists, Inc. 

Water-soluble, enzyme-extractable, and total pentosans were estimated by the orcinol method in whole wheat, barley, oats, sorghum, and brown rice, in laboratory abraded grains, in pearlings from abraded grains, and in commercial samples of brewers' dried grain, wheat bran, oat hulls and bran, rice hulls and bran, corn bran and soybean hulls. The enzyme-extractable pentosans were estimated after treatment with a multi-component system of Trichoderma viride. Total pentosans were estimated after hydrolysis with 2N HCl at 100 C, neutralization, and fermentation with fresh, compressed bakers' yeast. Pearled grains generally contained less water-soluble, enzyme-extractable, and especially total pentosans than the whole grains; this was reflected in the high concentrations of pentosans in the pearlings. Among the commercial milling by-products, water-soluble pentosans were highest in soybean hulls (1.55%) and wheat bran (1.02%). Enzyme-extracted pentosans were highest in brewer's dried grains (3.94%), soybean hulls (3.81%), and oat bran (3.16%). Total pentosans were highest in corn bran (34.72%) and wheat bran (22.53%). Oat bran (4.07%) and rice bran (5.63-7.15%) were low in total pentosans. The ranges were 0.1- 1.6% for water-soluble, 0.2-3.9% for enzyme-extractable, and 4.1-34.7 for total pentosans. Distinct linear regression lines were established for the plots between ash and total pentosan for individual grains from the abrasion series. Positive correlation coefficients between protein and enzyme-extractable pentosans were significant at the 0.01 level for the samples from the abrasion series, commercial by-products, and combined samples.