Isolation and characterization of arabinoxylans from wheat bran and study of their contribution to wheat flour dough rheology

Authors: KAUR, AMRITPAL - Guru Nanak Dev University; Yadav, Madhav; SINGH, BALWINDER - Folkhalsan Research; BHINDER, SEERAT - Guru Nanak Dev University; Simon, Stefanie; SINGH, NARPINDER - Guru Nanak Dev University

Submitted to: Carbohydrate Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/3/2019
Publication Date: 6/4/2019
Citation: Kaur, A., Yadav, M.P., Singh, B., Bhinder, S., Simon, S., Singh, N. 2019. Isolation and characterization of arabinoxylans from wheat bran and study of their contribution to wheat flour dough rheology. Carbohydrate Polymers. 221:166-173. https://doi.org/10.1016/j.carbpol.2019.06.002.
DOI: https://doi.org/10.1016/j.carbpol.2019.06.002

Interpretive Summary: Wheat bran, a by-product of the wheat dry milling process, is a good source of dietary fiber with numerous health benefits. Wheat bran contains both soluble and insoluble fiber, the soluble fiber is composed of mainly a carbohydrate polymer called “arabinoxylan”. The arabinoxylans exhibit different properties such as hydration, water solubility, viscosity etc. Arabinoxylans are classified as water extractable arabinoxylans and alkali extractable arabinoxylans. The addition of arabinoxylan to wheat flour influence water absorption, flow behavior and mixing properties of the dough due to their high-water binding capacity. The above benefits prompted us to isolate and characterize the water extractable arabinoxylans and alkali extractable arabinoxylans from wheat bran of four varieties (HD-3086, HD-2947, HS-490 and C-306) and study their relationship with the dough properties of their flours. The HD 3086 and HD2947 wheat varieties contain a higher amount of total water and alkali extractable arabinoxylans than HS-490 and C-306 varieties. Due to a higher amout of arabinoxylans, the flour from wheat varieties HD 3086 and HD 2947 make a higher quality dough than the flour from the C-306 and HS-490 varieties. This study can be of great value to the US and Indian agricultural industries and farmers by helping to understand the valuable properties of the arabinoxylan fractions. It will also increase the value of wheat milling by-products benefiting U.S. and Indians wheat processors.

Technical Abstract: The water-extractable and alkali extractable hemicellulose-A, hemicellulose-B and oligosaccharide fractions were isolated from bran of four wheat varieties. The flour from HD 3086 and HD2947 variety have a slightly higher percentage of protein than the other two varieties. The wheat bran from all varieties were rich in protein content (12.45 - 16.97%). The yield of Water extractable hemicellulose A, water extractable hemicellulose-B, and water extractable oligosaccharides were lower than the yield of alkali extractable hemicellulose-A, alkali extractable hemicellulose-B and alkali extractable hemicellulose-oligosaccharides. The sugar composition of these fractions showed that they were typical arabinoxylans containing arabinose and xylose with some other sugars such as rhamnose, galactose, glucose, galacturonic acid and glucuronic acid. HD 3086 and HD2947 wheat varieties which make a high-quality dough, had higher percent of alkali extractable hemicellulose-B and both water extractable-oligosaccharides and alkali extractable-oligosaccharides in comparison to the other two wheat varieties. These two wheat varieties also have high G' and G" values, which are good quality dough-making characteristics.