Significance of thermal transitions on starch digestibility and firming kinetics of restricted water mixed flour bread matrices

Abstract

The impact of wheat (WT) flour replacement up to 45% (weight basis) by incorporation of ternary 25 blends of teff (T), green pea (GP) and buckwheat (BW) flours on the thermal profiles of quaternary blended 26 dough matrices have been investigated by simulating baking, cooling, and storage in differential scanning 27 calorimeter (DSC) pans. Endothermal transitions related to suitable patterns for low and slow starch 28 hydrolysis, softer crumb and retarded firming kinetics in blended breads include delayed temperatures for 29 starch gelatinization, and for the dissociation of amylose-lipid complex. In addition, a) higher stability for the 30 amylose-lipid inclusion complex, b) lower energy for starch gelatinization, c) lower limiting melting enthalpy 31

Functional and Thermal Behaviours of Heat-Moisture-Treated Starch-Rich Wheat-Based Blended Matrices: Impact of Treatment of Non-wheat Flours

“…1a). In agreement with previous results (Collar et al, 2015), no significant change (p>0.05) in the magnitude of the endotherm was observed with ageing (Fig. 1a).…”

“…Thermal properties regarding starch retrogradation, and amylose-lipid complexation of fresh and stored blended bread samples were assessed in a Differential Scanning Calorimeter Perkin-Elmer DSC-7 (Norwalk, USA) according to the method previously reported by Collar et al (2015). Sample pans containing about 50-70 mg of bread were scanned at 25°C for 1 min, and then heating from 25 to 130°C at a rate of 10°C/min.…”

“…2b). Data of starch retrogradation on ageing were modelled using the Avrami equation, that provides a convenient means to quantify crystallization kinetics and make comparisons among similar starch-based systems submitted to different processing treatments, as previously reported (Collar et al, 2015). Results on the model factors ΔH0, ΔH∞, nr, and kr for the enthalpy of amylopectin retrogradation are compiled in Table 2.…”

Rheological and thermal properties of dough and textural and microstructural features of bread obtained from nixtamalized corn/wheat flour blends

“…Under these conditions, starch granules are unable to undergo a complete gelatinization process, leading only to partial swelling of starch granules (Day et al, 2013). In fact, the unavailability of water causes that the remaining ungelatinized starch granules to melt at higher temperatures, and to encompass variable energy requirements to disorganize their structure (Collar et al, 2015). In this way, starch granules integrity remains even after baking of the dough formulations.…”

“…The endothermic effects were displayed over a wide range of temperatures (73.33e174.41 C). Collar et al (2015) reported that thermal transitions of bread formulations are specific of the non-wheat flour substitutions. Baking of bread occurred over this temperature range promoting microstructure accommodation, as well as lipid-starch and lipid-protein degradation.…”