Different thermal treatments of highland barley kernel affect its flour physicochemical properties by structural modification of starch and protein. (1st September 2022)

• Record Type: Journal Article
• Authors: Wang, Haoran; Li, Zaigui; Wang, Lili; Cui, Steve W.; Qiu, Ju
• Is Part Of: Food chemistry. Volume 387(2022)
• Publication Date: 2022-09-01
• Subjects: HB highland barley -- SS superheated steam -- DS damaged starch -- SS-140 SS treatment performed at 140 °C for 6 min -- SS-160 SS treatment performed at 160 °C for 6 min -- SS-180 SS treatment performed at 180 °C for 6 min -- DSC differential scanning calorimetry -- To onset temperature -- Tp peak temperature -- Tc conclusion temperature -- ΔH enthalpy -- DG degree of gelatinization -- TGA thermogravimetric analysis -- RVA rapid visco analyzer -- G′ storage modulus -- G″ lost modulus -- FTIR Fourier transform infrared spectroscopy -- XRD X-ray diffraction -- SEM scanning electron microscopy -- CLSM confocal laser scanning microscopy -- PV peak viscosity -- TV trough viscosity -- FV final viscosity -- tan δ loss tangent; Highland barley -- Superheated steam treatment -- Damaged starch -- Starch molecular structure -- Pasting properties -- Gel rheological properties; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.132835
• Languages: English
• ISSNs: 0308-8146

Abstract

Graphical abstract: Highlights: Thermal treatments changed starch arrangement and protein secondary structure. Superheated steam led to tightest starch granules aggregation embedded in protein. Superheated steam at 180 °C decreased the damaged starch level. Superheated steam at 180 °C delayed starch retrogradation. Superheated steam at 180 °C decreased the elasticity and viscosity of gel. Abstract: Highland barley (HB) has become popular due to nutritional benefits, and thermal treatment could broaden its application. In this study, superheated steam (SS) as a novel commercially thermal treatment was compared with other traditional heating (steam and roasting). The physiochemical properties of treated HB kernels and subsequent produced flour were investigated. After thermal treatments, gelatinization enthalpy was decreased by 38.39% and the degree of gelatinization was increased by 38.40%. SS at 180 °C (SS-180) induced the highest thermal stability, lowest viscoelasticity gel and delayed the starch retrogradation compared to other treatments. Meanwhile, SS-180 caused lowest short-range order and relative crystallinity of starch along with changes in protein secondary structure. Particularly, SS-180 decreased damaged starch content by 6.44% due to starch granules closely wrapped by glue-like protein, while steam and roasting increased it by 32.92% and 21.40%, respectively. Overall, SS treatment is most effective to improve the physiochemical properties of HB.