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Abstract: Various procedures have been used to produce preparations of retrograded starch, by subjecting it to acetylation with methods used in the food industry. The resultant starch preparations were evaluated for their degree of acetylation through titration, swelling power and solubility in water at 80 °C, and saccharification dynamics as affected by amyloglucosidase. Rheological properties of pastes and gels of native starch and modified starch preparations were characterized with the use of a sweep temperature test as a dependency of the storage modulus (G′) and loss modulus (G″) on temperature. In addition, flow curves of pastes were plotted and mechanical spectra of gels of the preparations examined were determined. These modifications had a significant effect on the preparations produced. Retrograded and acetylated starch preparations were characterized by greater solubility in water and greater swelling power, and were less susceptible to amyloglucosidase than the non-acetylated preparations. Rheological properties of the pastes and gels were affected by the methods of their production. Acetylation was found to significantly affect a decrease in the storage modulus value during heating. Pastes of the native starch and modified starch preparations were characterized by the non-Newtonian flow, shear thinning with a tendency to yield stress. In turn, the mechanical spectra demonstrated that - in the concentration applied - both native starch and modified starch preparation were forming weak gels. [Copyright &y& Elsevier]

The purpose of this work was to study the influence of maltodextrins produced from chemically modified starches (stabilised, cross-linked, and double modified) on the stability and rheological characteristics of foam produced from egg albumin. A significant effect was found, related to the type of chemically modified starch used to produce the maltodextrins, on the stabilising properties of the latter and on the viscoelastic properties of the foam systems. Maltodextrins produced from distarch phosphate exhibited the best foam stabilising properties, while maltodextrins from acetylated starch had no favourable effect on the stability of the foam. Moreover, it was found that foam stability decreased as the dextrose equivalent (DE) value of the maltodextrin increased. The foams stabilised with maltodextrins exhibited viscoelastic properties, with domination of the storage modulus over the loss modulus, and behaviour similar to weak gels. The susceptibility of the foams to deformation was dependent on the type of maltodextrin and its DE value. The foam stabilised with the DE 6 maltodextrin produced from acetylated distarch phosphate was the most resistant to deformation, while foam with maltodextrin produced from acetylated starch was the least resistant to deformation. [ABSTRACT FROM AUTHOR]

A growing demand for gluten-free products is caused by an increasing number of diagnosed celiacs, but also by a trend to eliminate any potentially allergenic proteins in a diet. The removal of gluten from food products traditionally based on wheat, has a significant impact on their structure and texture. It is not an easy task to adjust a recipe for gluten-free products, which would give a product with sensory attributes, nutritional value and consumer acceptance comparable to traditional food. The main raw materials involved in such formulations are starches and flours of various botanical origin in which starch is the main component. Their properties could be additionally modified by appropriate structure- and texture-forming ingredients or additives, including various hydrocolloids, processing aids and stabilizers, as well as nutrients. The role of starch in such systems is always important, as its proper choice and treatment could significantly affect properties of the final product. This literature review describes the role of starch as a major ingredient of gluten-free food products. It presents starch molecular and physical properties, shows differences between various types of this biopolymer and their influence on product characteristics. [ABSTRACT FROM AUTHOR]

Abstract The aim of the study was to evaluate the influence of waxy starch (WS) on structure formation and staling retardation in starch based gluten-free bread. Corn/potato starch mix in bread formulation was partially replaced with waxy corn/waxy potato starch mix, and the resulting changes in rheological properties of the dough and quality of the bread, as well as its staling kinetics were monitored. It was concluded that the presence of waxy starch modified rheological properties of the dough, causing an increase in values of storage and loss moduli (G′ and G″, respectively) and zero shear viscosity, due to the increased swelling capacity of waxy starch. Moreover 10% replacement of original starch mix with WS mix had the optimal effect on bread volume, accompanied with only slight changes in crumb structure. The presence of WS in amounts 10–15% had a positive impact on texture characteristics of bread crumb, reducing its hardness and chewiness in comparison to control and limiting increase of these parameters during storage. WS added at levels 10–15% caused a reduction in enthalpy of retrograded amylopectin, which indicates, that it could be an effective factor reducing staling of starch based gluten-free bread. Highlights • Waxy starch was used as anti-staling agent in gluten free-bread. • Waxy starch modified rheological characteristics of dough. • 10% addition of waxy starch caused an increase in bread volume. • 10–15% addition of waxy starch reduced bread hardness during storage. • Waxy starch caused a reduction of amylopectin recrystallization during storage. [ABSTRACT FROM AUTHOR]

The aim of the study was to use hemp flour and hemp protein concentrate as natural nutritional and structure-forming agents in gluten-free starch bread and to determine their impact on rheological properties of dough and quality and staling rate of bread crumb. The influence of hemp preparations on rheological characteristics of gluten-free dough was significant. Replacing a portion of starch with hemp flour resulted in a weakening of dough structure, which became more susceptible to deformation, while 20% share of hemp protein concentrate reinforced the structure of the tested dough. The presence of both investigated hemp preparations significantly improved nutritional value of bread. The changes involved increased levels of fiber from 15.2 up to 61.0 g/kg, and dietary fiber from 29.3 to 90.0 g/kg. Supplementation of bread with hemp protein favorably influenced the color of crumb by reducing its lightness from 62.3 to 40.8 and increased bread volume from 633 to 878 mL. Bread enriched with hemp preparations was characterized by improved sensory acceptance, especially in respect to color and flavor. Supplementation of starch bread with preparations based on hemp limited crumb hardening and amylopectin recrystallization during storage. [ABSTRACT FROM AUTHOR]

Mesquite flour at ratios of 5%, 7.5%, and 10% were used as substitute for starches in gluten-free bread formulations. The 7.5% and 10% share of mesquite flour, changed the rheological characteristics of the dough, causing an increase in the value of the storage (G′) and loss (G″) moduli, and a decrease of its susceptibility to stress with a simultaneous increase in zero shear viscosity. Addition of mesquite flour promoted a slight decrease (<10%) in bread volume, an increase in cell density, and a decrease in the number of large pores >5 mm compared to the control sample. The addition of 5% mesquite flour caused the greatest decrease in bread volume and porosity. The presence of mesquite flour significantly affected crumb color, which decreased its lightness and increased the proportion of yellowness. Sensory evaluation revealed an increase in the acceptability of crumb color, smell, and taste. The bread's crumb with 7.5% and 10% mesquite flour had considerably lower hardness during storage compared to the control sample, indicating the limitation of the staling process. Thus, the results obtained indicate that mesquite flour can be a valuable component of starchy gluten-free bread, improving its shelf life and sensory acceptability. • Impact of mesquite flour on the properties of gluten-free dough/bread was assessed. • Mesquite flour strengthened the structure of the gluten-free dough. • Crumb with mesquite was softer during storage than control indicates slower staling. • Sensory evaluation showed better acceptability of the crumb color, smell, and taste. • Mesquite improve shelf life and acceptability of starchy bread. [ABSTRACT FROM AUTHOR]

The aim of the study was to apply water extract of linseed as structure forming agent in gluten free baking and to assess their influence on rheological properties of the dough and quality of the bread, especially its staling rate. The analysis of rheological properties of the dough structured with linseed mucilage proved, that in the absence of external stress the systems reveal rheological properties comparable with control sample. They are however much more susceptible on mechanical strain. The replacement of guar gum and pectin with linseed mucilage improved sensory acceptance of the bread and had limited influence on texture and staling of the bread. The results concerning organoleptic and physicochemical parameters of the bread indicate that freeze-dried extract of linseed could be applied as natural and effective structure forming agent in this type of bakery products. [ABSTRACT FROM AUTHOR]