Effect of Different Extrusion Parameters on Dietary Fiber in Wheat Bran and Rye Bran

Abstract

Wheat bran and rye bran are mostly used as animal feed today, but their high content of dietary fiber and bioactive components are beneficial to human health. Increased use of bran as food raw material could therefore be desirable. However, bran mainly contains unextractable dietary fiber and deteriorates the sensory properties of products. Processing by extrusion could increase the extractability of dietary fiber and increase the sensory qualities of bran products. Wheat bran and rye bran were therefore extruded at different levels of moisture content, screw speed and temperature, in order to find the optimal setting for increased extractability of dietary fiber and positive sensory properties. A water content of 24% for wheat bran and 30% for rye bran, a screw speed of 400 rpm, and a temperature of 130 °C resulted in the highest extractability of total dietary fiber and arabinoxylan. Arabinoxylan extractability increased from 5.8% in wheat bran to 9.0% in extruded wheat bran at those settings, and from 14.6% to 19.2% for rye bran. Total contents of dietary fiber and arabinoxylan were not affected by extrusion. Content of β-glucan was also maintained during extrusion, while its molecular weight decreased slightly and extractability increased slightly. Extrusion at these settings is therefore a suitable process for increasing the use of wheat bran and rye bran as a food raw material.

Extrusion-Cooking Modifies Physicochemical and Nutrition-Related Properties of Wheat Bran

“…On the contrary, Yan et al [21] observed an increase in the water-binding capacity of wheat bran after extrusion-cooking. Moreover, it was shown that dietary fibre was solubilised during extrusion-cooking [20][21][22] due to the conversion of water-unextractable arabinoxylan (WU-AX) to water-extractable arabinoxylan (WE-AX) and the release of β-glucan [22,23].…”

Effect of extrusion on physicochemical, nutritional and antioxidant properties of breakfast cereals produced from bran and dehydrated naranjita pomace

“…The bran presents a high content of dietary fiber, vitamins, minerals, as well as phenolic compounds. The consumption of these compounds has been linked to important benefits in human health since they could help reduce the risk of suffering different diseases (Andersson, Andersson, Jonsäll, Andersson, & Fredriksson, 2017). Among the types of bran that can be used for the production of breakfast cereals are the oat-bran and wheat-bran.…”

Advances on the Valorisation and Functionalization of By-Products and Wastes from Cereal-Based Processing Industry

“…Arabinoxylans Fermentation [102][103][104] Ultrasonic/microwave [105,106] Enzymatic treatment [107][108][109][110] Milling fractions [111][112][113] Alkaline treatment [114][115][116][117] Nixtamalization [118] Starch removal [119] Extrusion [80,86,89,120] Subcritical water treatment [119,121] β-glucans Ultrasound [122] Roller-milling/pearling [123] Milling [124][125][126] Fermentation [127,128] Enzymatic treatment [129,130] Extrusion [131][132][133][134] Subcritical water treatment [119,135,136]…”