Film-forming modifications and mechanistic studies of soybean protein isolate by glycerol plasticization and thermal denaturation: A molecular interaction perspective.

Plasticizer and thermal denaturation are indeed important factors for soybean protein film formation. The objective of the study was to investigate the effects of glycerol and thermal denaturation on the film-forming performances of soybean protein isolate (SPI) and elucidate the underlying mechanisms. From the results, glycerol had almost no effect on the protein's secondary and tertiary structures.

Film-forming properties and mechanisms of soy protein: Insights from β-conglycinin and glycinin.

Extensive research has been conducted on soy protein films; however, limited information is available regarding the influence of the major components, β-conglycinin (7S) and glycinin (11S), on the film-forming properties of soy protein. This study aimed to isolate the 7S and 11S fractions in order to prepare films and investigate the impact of varying 7S/11S ratios on the film-forming solutions (FFS) and film properties. The findings revealed that higher 11S ratios led to increased protein aggregation, consequently elevating the storage modulus (G') of the FFS.

Breaking the temperature limitation of zein-rice starch dough by microwave pre-gelatinization: Morphological, structural and rheological properties of the dough.

Zein has gluten-like viscoelasticity, but its use is limited due to high glass transition temperature (T). To break the temperature limitation of zein-starch dough, microwave heating was used to pre-gelatinize a partial of the starch with zein, and then the remaining was added and kneaded to form a dough. Pre-gelatinized doughs formed by rice starch (PRS), zein-starch (PUZS), and extruded zein-starch (PEZS) were included in this study.

Influence of pH and ionic strength on the physicochemical and structural properties of soybean β-conglycinin subunits in aqueous dispersions.

Understanding the impact of pH and ionic strength on the physicochemical and structural properties of soy proteins at subunit level is essential for design and fabrication of many plant-based foods. In this study, soybean β-conglycinin and its subunit fractions αα' and β were dispersed in solutions with different pH values (3.7, 7.

Impacts of ethanol-plasticization and extrusion on development of zein network and structure of zein-starch dough.

To improve the viscoelasticity of zein in gluten-free dough, ethanol-plasticization and extrusion modification were employed. The peak viscosity of UZS (unextruded zein-starch) flour and EZS (extruded zein-starch) flour with ethanol (10 %, v/v) increased from 1340.0 to 1996.

Effect of screw speed, temperature and moisture on physicochemical properties of corn gluten meal extrudate.

Background: Corn gluten meal (CGM) is the main by-product of corn starch with rich protein and dietary fiber. The extrusion of CGM with a twin-screw extruder aimed to expand the novel utilization of this plant-protein resource. The impacts of screw speed, extrusion temperature, and material moisture on physicochemical properties of the extrudates were assessed.

Impacts of extrusion temperature and α-subunit content on structure of zein extrudate and viscoelasticity of the plasticized network.

To elucidate the effects of temperature and α-subunit content on the physicochemical characteristics and structure of zein, three zeins (commercial zein, α-subunit-rich zein, and total zein) with high to low α-subunit content were extruded at 80, 100, 120, and 140 °C, respectively. The mechanical properties, peptide distribution, particular size, morphological changes in self-assembly, and intermolecular forces of the extrudates were determined; the extrudates were plasticized by acetic acid, and the rheological properties of the resulted viscoelastic network were measured. With the temperature increase, the solubility of zein extrudates decreased, and the peptide weight of α-subunit-rich zein and total zein increased.

Heat-induced aggregation of subunits/polypeptides of soybean protein: Structural and physicochemical properties.

To reveal the nature of thermal aggregation of soybean protein at subunit level, structure and physicochemical properties of αα'- and β-subunits isolated from β-conglycinin, acidic polypeptide, and basic polypeptide from glycinin, as well as β-conglycinin and glycinin, were characterized before and after heat treatment. The transmission electron microscopy (TEM) images showed that β-conglycinin, αα'-subunits and acidic polypeptide formed regular thermal aggregates, which exhibited high solubility, high ζ-potential value, and small particle size. While glycinin, β-subunit, and basic polypeptide aggregated to insoluble clusters with large particle size distribution.

Application of zein in gluten-free foods: A comprehensive review.

The gluten-free food market is growing worldwide. Zein is a promising gluten substitute in the gluten-free system due to its similar viscoelastic properties to gluten. However, a few existing reviews are limited to the zein characteristics and the application of zein in gluten-free bread and noodles while lacking a comparison of basis information between zein and gluten and the application in other foods, like meat analogue.

Physicochemical properties and protein structure of extruded corn gluten meal: Implication of temperature.

Corn gluten meal is a by-product of corn starch production. To extend its application in the food industry, the extrusion of corn gluten meal was conducted, and the effects of temperature (80, 100, 120, and 140 °C) on physicochemical properties and protein structure of the extrudates were investigated. Corn gluten meal was texturized when the extrusion temperature reached 120 °C, and puffed when it reached 140 °C.

The role of the extension region on the structural and physicochemical characteristics of the α-subunit of β-conglycinin: implications of pH value and ionic strength.

Background: To clarify the role of the extension region on the structure-functional relationship of the α-subunit of β-conglycinin, α-subunit and its segment of the core region (αc-subunit) were expressed via an Escherichia coli system. Their physicochemical properties were compared under acid, neutral or alkaline conditions (pH 4.0, 7.

Effect of potato flour on quality and staling properties of wheat-potato flour bread.

To elucidate the impact of potato flour (PF) on quality changes and staling characteristics of the composite bread from wheat-potato flour (WPF), the physicochemical (specific volume, colority, sensory value, texture, and viscosity) properties, and staling (X-ray diffraction and water migration) properties of bread were investigated. The quality of composite bread was comparable to wheat bread when addition level of PF at 20%, but decreased when the addition level increased to 30% or more, and became unacceptable at 50%. A chewy mouthfeel and an elastic and none-crumbly texture were observed on composite bread, which had higher hardness than wheat bread, and could keep on both longer linear distance and higher linear force during compression test.

The effects of extruded corn flour on rheological properties of wheat-based composite dough and the bread quality.

The effects of extruded corn flour (ECF) on the rheological properties of the wheat-based composite dough and quality of the bread were investigated. The RVA results of the composite flour with ECF showed weak thermal viscosity and resistance to starch retrogradation. Mixolab tests revealed that the water absorption capacity increased with the increasing amount of ECF, while dough development time (DT) and dough stability (ST) showed a downward trend, and the composite dough became more resistant to retrogradation.