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Starches with different amylose (AM)/amylopectin (AP) ratios (waxy potato: WxPS; regular potato: PS; high AM corn: HACS) are hydroxypropylated (HP, two levels) and subsequently acid‐thinned (AT) to produce dual‐modified samples. The physicochemical characteristics and techno‐functional properties of the solutions are investigated, and the data are evaluated statistically (analysis of variance). Differential scanning calorimetry gelatinization experiments reveal a reduction of the transition temperatures particularly due to HP. The subsequent AT decreases the specific enthalpy significantly. HACS samples have lower solubility (S) compared to their potato‐based counterparts (WxPS and PS), but HP enhances the starch's S. The S of the AP of the HACS samples is comparatively high, and HP particularly facilitates the additional solubilization of AM. Dual‐modified samples show characteristics of S similar to the corresponding HP samples. Or particular note, the HP‐modified WxPS and PS, respectively, tend to cause molecular degradation of the polymers dissolved. The hot paste viscosity is impacted significantly by all varied factors. [ABSTRACT FROM AUTHOR]

Granular potato starch is modified using the debranching enzyme isoamylase. The modification is performed in aqueous suspension (40% w/w) at 35 °C by grading the volume (100, 250, and 400 µL/50 g of starch, 200 U · mL−1) of enzyme solution added. The starch products obtained are comprehensively investigated in terms of morphological (scanning electron microscopy), structural (X‐ray diffraction), thermal (differential scanning calorimetry), techno‐functional (solubility, hot paste viscosity, gel strength), and molecular properties (size exclusion chromatography‐multi angle laser light scattering‐differential refractive index detection). The granular integrity is basically preserved after modification and a molecular degradation predominantly of the amylopectin by debranching is proved. However, a slight reduction of the weight average molar mass of the amylose fraction is found too. In addition, the intended partial molecular degradation of the starch polysaccharides, the effect of the preparation procedure including washing with ethanol and grinding impacts several starch characteristics conspicuously. [ABSTRACT FROM AUTHOR]

The use of dietary fiber enriched flour for bread making is steadily gaining importance because of its proven health benefits. The objective of the work was to assess the impact of xanthan (XG) and guar gum (GG) on the pasting profiles, stickiness and extensional properties of β-glucan incorporated brown wheat flour (BWF/BGC) composite dough systems. Water absorption of the blend flour increased significantly with increasing the concentration of hydrocolloids. Loading of both hydrocolloids (0.125–0.5 g/100 g) produced similar values of extensograph and stickiness parameters, nonetheless, it was observed that an addition of 0.25 g/100 g hydrocolloid could be effective to maintain a desirable dough texture. Biaxial measurement indicated that the incorporation of 0.25 g/100 g hydrocolloids improved the dough structure of BWF/BGC. The pasting viscosities of the blend dough including hot paste, cold paste and final viscosity increased significantly with increasing the hydrocolloids concentration. The pasting properties of BWF/BGC influenced by individual hydrocolloid, and the difference could be attributed by the complex formation among swelled starch, leached amylose and hydrocolloids. [ABSTRACT FROM AUTHOR]

Influence of high-pressure (HP) treatment (400-600 MPa, 10 min) on chestnut flour (CNF) dispersions was examined. The particle size, total starch, and resistant starch contents were not influenced by the HP treatment. DSC, XRD, SEM, and rheometric measurement confirmed that the applied pressure was not adequate for the complete gelatinization of the chestnut starch in the dispersion. The mechanical rigidity of CNF in dispersions (flour/water = 1:2) increased significantly with increasing the pressure. Pasting profiles of the HP-treated sample varied significantly from the sample without the pressure treatment. Overall, the work revealed that chestnut starch was pressure-resistant within the studied pressure range. [ABSTRACT FROM AUTHOR]

A matrix of 27 acid‐thinned (AT) potato starch (PS) samples is prepared in a laboratory scale in slurry by gradation of the process parameters temperature (30, 40, and 50 °C), acid concentration (0.3, 0.6, and 0.9 m HCl) and time (4, 10, and 20 h), and is investigated in terms of functional properties (range of molar mass [Mw] between 17.7 × 106 and 1.95 × 104 g mol−1). The solubility (S) increased basically with a higher degree of molecular degradation and disintegration temperature, and the viscosity decreased systematically with decreasing Mw and increasing disintegration temperature. The existence of a specific Mw range of the starch to achieve highest gel strength is proved. However, an impact of the molecular properties on the light transmittance (Tgel) can be excluded, since all starch gels are opaque. A correlation between the strength and the specific non‐freezable bound water content (wnf) of the gels is found. High gel strength is accompanied by comparatively low wnf. In particular, the viscosity (processing) and the gel strength (final product characteristic), which are important technofunctional properties for the industrial application of AT starches, are found to be directly correlated to the Mw of the starch product. Moreover, the latter is controllable by the hydrolysis process parameters. [ABSTRACT FROM AUTHOR]