Pulsed electric field treatment of wheat bran to improve arabinoxylan extraction

Sammanfattning: Valorization of agricultural and industrial by-products reduces the environmental impact of food production. Innovative low impact processes for food processing further limit the contribution and additionally enhances the generation of novel health-promoting foods. Wheat bran (WB) is an industrial by-product produced during milling which currently have limited use for food applications, despite its exceptional nutritional content. Arabinoxylan is the main non-starch polysaccharide in WB and can be used to improve the quality and physiochemical properties of foods as well as improve the nutritional value. The aim of this study was to determine if PEF enhances the extraction yield of extracted arabinoxylan and modulates the chemical composition of arabinoxylan extracts. It was hypothesized that pulsed electric field technology (PEF) can aid extraction of arabinoxylans (AX) from WB. WB was treated with highest possible field strenght (3,7 kV/cm), a frequency of 2Hz, pulse width of 5 μ s and either 100, 250, 500. 750 or 1000 pulses. PEF had a significant effect on total carbohydrate content of AX extracts (p<0,05). There was an increase in carbohydrate content for AX extracts treated with 250, 500 and 1000 pulses. PEF additionally decreased the A/X ratio. PEF treated AX extracts had ratios between 0,92-0,84. The result confirms that PEF increases the purity and changes the chemical composition of alkaline extracted AX. PEF treatments with 1000 pulses is most effective in increasing purity. Further studies should examine the effect of different PEF parameters on extraction yield and physiochemical properties of AX extracts.