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Background and objectives: Flour heat treatment is commonly used to improve dough and bread quality. This study creatively proposed applying partial preheated dough (PPHD) to frozen dough and evaluated bread characteristics and its internal mechanism systematically. Findings: Results suggested that moderate PPHD level presented higher specific volume, softer hardness, more appealing brown crust color and more uniform texture of frozen dough bread. Moisture status analysis showed that PPHD restricted the mobility of overall water molecules and the migration from bound water to semi‐bound water. DSC and RVA results suggested that the inter‐ and intramolecular association of starch granules, leading to abundant formation of hydrogen bonds, strengthened the gluten matrix network. Besides, gelatinized starch granules in PPHD served as a paste to promote the cross‐linking of starch and gluten, which was observed by SEM. Conclusions: Partial preheated dough inhibited ice recrystallization by restricting water migration and formed a highly networked starch–gluten structure that delayed its destruction during freezing. Significance and novelty: This study demonstrated obvious improvement of PPHD on frozen dough quality and further explained the mechanism systematically. Moreover, the method was innovative, simple, and easy to operate, so it could help to promote the development of the frozen dough industry. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of heat treatment on the molecular structure of starch and protein in wheat flour and to establish a correlation between the changes in molecular structure and the resulting effects on the pasting properties of the flour. Heat treatment increased the pasting viscosity and pasting temperature with the extent of heat-treated time and temperature. Moreover, the water absorption indexes, swelling power, and gelatinization enthalpy of heat-treated flour were higher than that of untreated flour, while the water solubility indexes were lower. The clustered starch granules and aggregated protein increased the particle size of flour after heat treatment. Additionally, heat treatment decreased the damaged starch content from 6.54% in native flour to 2.94% in treated flour (100 °C, 30 min), causing an increase in the short-range order structure and relative crystallinity of starch. The aggregated protein induced by heat owned the lower free sulfhydryl content and higher SDS-insoluble protein and β-sheet structure. The pasting properties variations were mainly correlated with the molecular structure changes of protein induced by heat. These results provided a theoretical basis for tailoring flour to produce wheat-based products with desired properties through the application of heat treatment technology. [Display omitted] • Heat treatment increased the pasting viscosity and pasting temperature of wheat flour. • Heat treatment induced the protein aggregation of wheat flour. • Heat treatment increased the crystallinity and short-range order structure of wheat flour. • The high viscosity in heat treated flour mainly related with the structural changes in protein. [ABSTRACT FROM AUTHOR]

This paper explored the impact of superheated steam (SS) treatment on the physicochemical, crystalline characteristics and in vitro digestibility of wheat starch. Upon SS treatment, treated samples showed lower swelling power, solubility, and viscosities, but had higher gelatinization temperature, which might be due to the partial gelatinization of starch granules. This agreed with micromorphology characterization, indicating the degradation of Maltese cross. In addition, SS treatment decreased the long-range crystalline and short-range order of starch, compared to native starch sample. This change of physicochemical and structural properties was responsible for the decrease of starch hydrolysis rate. Meanwhile, SS treatment obviously increased the slowly digestible starch (SDS) and resistant starch (RS) content from 10.6% to 7.9% (native starch) to 17.2% and 13.6% (150 °C, 1 min), respectively. This knowledge indicates that superheat steam technology possibly is a promising strategy in starch modification. [Display omitted] • Superheated steam (SS) treatment induced partial gelatinization of wheat starch. • SS treatment destroyed the long-range crystalline structure of wheat starch. • SS treatment increased resistant starch contents of wheat starch. [ABSTRACT FROM AUTHOR]