The proximate analysis of wheat flour carbohydrates. III.—the estimation of the hemicellulose fraction

Abstract

The composition of the hemicellulose fractions of wholemeal and flours of about 70s; extraction in terms of anhydro-arabinose, xylose and uronic acid units has been inwstigated. It has been shown that the hemicelluloses, on distillation with hydrochloric acid, behave in the same manner as an equimolecular mixture of arahinose and xylose. Xylose is a suitable standard for the distillation process, and the ' xylose equivalent ' of a wheat fraction multiplied by 0.97 is a quantitative measure ol the hemicellulose present, pro\-ided this is not less than 1,8:/,.

Characterization of White-Rotted and Brown-Rotted Rice Straw by X-Ray Photoelectron Spectroscopy

“…Composition analysis ofrice straw before and öfter biodelignification \\ Cellulose, hemicellulose (äs Pentosans) and lignin contents of rice straw before and after biodelignification were analysed by the anthrone method (Updegraff 1969), furfural estimation method (Fräser and Holmes 1957) and acetyl bromide technique (Morrison 1972), respectively.…”

Availability to pigs of amino acids in cereal grains

“…On the other hand, the ADF content of wheat and barley, which represents the combined contents mainly of cellulose and lignin, had little influence on protein digestibility. Hemicelluloses occur both in wheat endosperm and bran (Fraser & Holmes, 1957). Assuming a composition (g/ky) of 150 bran, 30 germ, 820 endosperm (Hinton, 1953), it can be calculated from the results of Fraser & Holmes (1959) that there is approximately 50% more hemicellulose than cellulose in wheat; of the total hemicellulose, approximately 27% occurs in the endosperm and 70% in the bran; in contrast, only 5% of the total cellulose was estimated to occur in the endosperm, the majority (89%) occurring in bran.…”

Biomethanation of white rotted and brown rotted rice straw

“…Small volume of digester liquid was taken for chemical analysis according to standard method. Pentosans were determined as``xylose equivalent'' by hydrochloric acid distillation to furfural [11]. Total solid, volatile solid and ash content were measured by Standard methods of APHA [12].…”