Effect of particle size reduction, hydrothermal and fermentation treatments on phytic acid content and some physicochemical properties of wheat bran

Abstract

With the aim of reducing phytic acid content of wheat bran, particle size reduction (from 1,200 to 90 μm), hydrothermal (wet steeping in acetate buffer at pH 4.8 at 55 °C for 60 min) and fermentation (using bakery yeast for 8 h at 30 °C) and combination of these treatments with particle size reduction were applied and their effects on some properties of the bran were studied. Phytic acid content decreased from 50.1 to 21.6, 32.8 and 43.9 mg/g after particle size reduction, hydrothermal and fermentation, respectively. Particle size reduction along with these treatments further reduced phytic acid content up to 76.4 % and 57.3 %, respectively. Hydrothermal and fermentation decreased, while particle size reduction alone or in combination increased bran lightness. With reducing particle size, total, soluble and insoluble fiber content decreased from 69.7 to 32.1 %, 12.2 to 7.9 % and 57.4 to 24.3 %, respectively. The highest total (74.4 %) and soluble (21.4 %) and the lowest insoluble fiber (52.1 %) content were determined for the hydrothermaled bran. Particle size reduction decreased swelling power, water solubility and water holding capacity. Swelling power and water holding capacity of the hydrothermaled and fermented brans were lower, while water solubility was higher than the control. The amount of Fe(+2), Zn(+2) and Ca(+2) decreased with reducing particle size. Fermentation had no effect on Fe(+2)and Zn(+2) but slightly reduced Ca(+2). The hydrothermal treatment slightly decreased these elements. Amongst all, hydrothermal treatment along with particle size reduction resulted in the lowest phytic acid and highest fiber content.

Effects of particle size and moisture content of maize grits on physical properties of expanded snacks

“…In addition, large and flat particles may contain more fat if they are speared from remaining germs in the maize grits since germ is high in fat and protein content. Similar results have been reported for wheat germ and wheat and rice brans with various particle sizes (Majzoobi, Darabzadeh, & Farahnaky, 2012; Majzoobi, Pashangeh, & Farahnaky, 2013; Majzoobi, Sharifi, Imani, & Farahnaky, 2013).…”

Fortified Blended Food Base: Effect of Co-Fermentation Time on Composition, Phytic Acid Content and Reconstitution Properties

“…Bilgiçli and İbanoğlu [20] reported a considerably higher reduction in the phytic acid content of tarhana, i.e., ~91% after 72 fermentation. The inter-study difference in the extent of phytic acid reduction with fermentation time may reflect differences in phytic content of the wheat cultivar used [34,35], differences in parboiling and milling conditions [36], pH of the milk/fermented milk, and/or the rate of drying.…”

Processing in the food chain: do cereals have to be processed to add value to the human diet?

“…In contrast, the process of fermentation in bread making (used to break down the tough outer hulls and increase cereal digestibility) may increase the content of phenolic compounds and enhance bioavailability (57) . Furthermore, fermentation in combination with hydrothermal treatment and particle size reduction has been shown to reduce phytic acid (58) , which in turn could increase the availability of minerals that are otherwise bound by phytic acid. Fermentation is widely used in bread making.…”