Physicochemical characterization of cereal bran cell wall with special reference to its rheological and functional properties

Abstract

The cell wall is a non-starch polysaccharide and consists of various bioactive moieties. In addition, it has many functional and nutraceutical properties. The main purpose of this present research was to extract the cell wall from different cereal bran and to characterize it for nutritional and bioactive properties. In addition, the effects of the cereal bran cell wall (CBCW) on functional and rheological properties of wheat flour were elucidated. For this purpose, the cell wall was extracted from different cereal bran (maize, oat, and wheat) via an enzymatic method and characterized for its monosaccharides and phenolic acids contents. Additionally, the rheological properties of wheat flour with the addition of CBCW were determined using the farinograph and mixograph. The results showed that the cell wall contents in oat bran (43.31 ± 1.41%) were higher than those in wheat (41.53 ± 0.09%) and maize bran cell walls (37.31 ± 1.05%). The maize bran cell wall has higher arabinose, xylose, galactose, and glucuronic acid contents, followed by oat and wheat bran cell walls. Furthermore, the oat bran cell wall contained higher total phenolic acid contents as compared to maize and wheat bran. Nevertheless, the ferulic acid content was high in the maize bran cell wall. Moreover, incorporation (2%) of CBCW significantly improved the rheological properties of wheat flour. The water absorption (66.04 ± 0.23%), dough stability (4.54 ± 0.6 min), peak height (66.02 ± 0.03BU), and mixing tolerance index (70.02 ± 0.07%) were high in wheat flour with the addition of oat bran cell walls followed by wheat and maize bran cell walls. Furthermore, the dough development time (6.75 ± 0.25 min) was the highest in the control sample and the lowest mixing time was observed in C4 (5.41 ± 0.12 min), while the softness of dough (139.4 ± 0.02%) was decreased more significantly through the oat cell wall than wheat and maize. Conclusively, CBCW contained different bioactive moieties that have numerous positive effects on the rheological and functional properties of wheat flour.

Keywords

• cell wall
• ferulic acid
• farinograph
• mixograph
• water-holding capacity