A proof-of-concept project compared extraction of arabinoxylans (AX) from sugarcane bagasse and 19 wheat bran via alkaline hydrogen peroxide followed by enzyme-assisted extraction with 20 combinations of feruloyl esterases and a xylanase. Bagasse contains comparable amounts of AX to 21 wheat bran, but with a much lower arabinoxylan substitution on the xylan backbone (A:X ratio of 22 around 0.2 compared with 0.6 for wheat bran), hence offering AX products with distinctive 23 functionality and potential end uses. In the current work, bagasse released its AX more readily than 24 wheat bran, and released a wider range of molecular weights. Use of feruloyl esterase and xylanase 25 enzymes on their own or following alkaline peroxide extraction did not enhance AX release 26 substantially; however, the xylanase appeared to be effective at reducing the size of AX molecules, 27 and there is scope to optimise the effects of enzymes to produce specific AX product fractions. As 28 bagasse frequently arises within the context of bioethanol production, integration of AX extraction 29 with ethanol production could allow economic production of a portfolio of AX products, as has been 30 demonstrated in principle for AX co-production in a wheat ethanol plant.

Xylo-and arabinoxylo-oligosaccharides (XOS and AXOS) are of interest for their prebiotic activity. The production of these oligomers might be accompanied with monosaccharides.The measurement of both oligosaccharides and monosaccharides usually requires two methods. The current work presents an HPAEC-PAD method based on gradient elution of aqueous solvents sodium hydroxide and sodium acetate, in contrast to conventional isocratic elution, for the simultaneous separation of 16 standards of monosaccharides, xylooligosaccharides, arabinoxylo-oligosaccharides and uronic acids using CarboPac PA 200 column. The presented method showed a stable baseline and high-resolution separation of the standards. The method showed acceptable accuracy and precision. Limits of Detection and Quantitation (LOD and LOQ) were estimated for all the standards. The method was applied to measure the activity of a commercial endoxylanase on wheat bran; a steady release of 2 xylose monosaccharide was observed. Enzyme action on oligosaccharide standards showed a preference for the larger oligosaccharides.

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The effects of sheeting on bread dough development and baked loaf quality were investigated, using Dynamic Dough Density and springback to quantify development, and examining effects of the sheeting regime on bread quality in terms of loaf volume and crumb structure. Bread doughs, with and without bran at different levels and particle sizes, were formed through a short mixing period, then sheeted through a benchtop manual sheeter at roll gaps of 6, 9 and 12 mm for different numbers of sheeting passes. The sheeting of doughs without bran increased dough expansion and baked loaf volume up to 12 sheeting passes. Loaves were larger after sheeting at a 6 mm roll gap, reflecting the greater gluten development at the smaller gap, although the crumb structure was less fine, with fewer gas cells and larger average gas cell diameters. The addition of bran decreased dough expansion and loaf volumes, with Fine bran and Coarse bran both more damaging than Medium bran, indicating the opportunity to optimise bran particle size to maximise bread quality. Sheeting was effective in alleviating the damaging effects of bran, with sheeting for 8 passes giving more dough expansion, larger loaf volumes and finer crumb structures than sheeting for 12 passes, indicating an even more damaging effect of bran when gluten is overstretched by sheeting. The work demonstrates the opportunity to enhance bread quality, particularly of healthy high-fibre breads, by employing sheeting to enhance gluten development and to offset the damage to gluten caused by the presence of bran.