This report describes a new procedure for serum amylase assay. A novel substrate, dyed amylopectin, is used that combines the advantages of saccharogenic and amyloclastic methods. Serum amylase hydrolyzes the dyed amylopectin into ethanol-soluble fragments, which are quantified colorimetrically after serum proteins and unhydrolyzed substrate are precipitated with alcoholic tannic acid. The subs...

The effects of sucrose on the physical properties of cassava starch aqueous systems were investigated at varied concentrations of cassava starch (5-15% w/w) and sucrose (0-40% w/w). The peak viscosity and the final viscosity during a gelatinization-retrogradation cycle were determined based on a Rapid Visco Analyzer (RVA) test. Sucrose generally increased the viscosity values, while such increm...

Yu K., Wang Y., Xu Y., Guo L., Du X. (2016): Correlation between wheat starch annealing conditions and retrogradation during storage. Czech J. Food Sci., 34: 79–86. The effects of annealing conditions on the degree of retrogradation (DR) in wheat starch were analysed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Three annealing parameters were varied, namely moisture (...

Amylose synthesis was obtained in vitro from purified Chlamydomonas reinhardtii starch granules. Labeling experiments clearly indicate that initially the major granule-bound starch synthase extends glucans available on amylopectin. Amylose synthesis occurs thereafter at rates approaching or exceeding those of net polysaccharide synthesis. Although these results suggested that amylose originates...

Polymer blends of cold water soluble starches (amylose or amylopectin soluble starch) with gelatin were prepared using solvent casting method. The solid state miscibility and polymer-polymer interactions between the constituent polymers were studied by fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorirmetry (DSC), light optical microscopy (OP...

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in starch. Iodine forms complexes with both amylose and long chains within amylopectin. After the addition of iodine to a starch sample, the maximum absorption of amylose and amylopectin occurs at 620 and 550 nm, respectively. The amylose/amylop...

Genome-wide association studies (GWAS) for amylose, amylopectin and β-glucan concentration in a collection of 254 European spring barley varieties allowed to identify 20, 17, and 21 single nucleotide polymorphic (SNP) markers, respectively, associated with these important grain quality traits. Negative correlations between the content of amylose and β-glucan (R = -0.62, P < 0.01) and amylopecti...

Waxy starch has an important influence on the qualities of breads. Generally, grain weight and yield in waxy wheat (Triticum aestivum L.) are significantly lower than in bread wheat. In this study, we performed the first proteomic and phosphoproteomic analyses of starch granule-binding proteins by comparing the waxy wheat cultivar Shannong 119 and the bread wheat cultivar Nongda 5181. These res...