Functional properties of defatted chickpea flour heat-induced gels

Defatted chickpea flour(DCF),which is a by-product of chickpea oil extraction industry,is rich in nutrients that are beneficial to human health.In this study,the effects of temperature and DCF variation on the rheological properties,water holding capacity,freeze-thaw stability and microstructure of DCF heat induced gels were investigated.The results showed that the viscoelasticity,frequency dependence,and resistance strength of heat induced gels increased significantly with the increase of temperature and DCF variation.The degree of denaturation and water retention of heat induced gels increased significantly with increased variables within the temperature and variation windows of 75℃ to 95℃ and 13%to 21%.The CLSM results revealed that variations of both temperature and DCF variation could cause the proteins in the heat induced gels to aggregate gradually and to form protein aggregations.When temperature or variation exceeded certain value(85℃ or 17%),the protein aggregations broke up and the protein clusters became smaller and more homogeneous.Therefore,the heat induced gels presented better water holding capacity,viscoelasticity,structural stability and gel property at a temperature of 95℃ or a DCF variation of 21%within the present experimental range.

Effects of the addition of edible polysaccharides on the properties of soybean protein isolate gels

The gel properties of soybean isolate protein(SPI)gels are susceptible to the influence of other components in food products,particularly edible polysaccharides.Therefore,six common edible polysaccharides were selected in this study to investigate their effects on the rheological properties,thermal properties,and microstructure of acid-induced soybean isolate protein self-assembled gels(SPIASG).The experimental results showed that the support capacity and creep recovery of SPIASG with added polysaccharides were higher than those of the control group without added polysaccharides,and the gel with Xanthan gum(XG)was the most effective.The hybrid gel,with added Condensed resin(CR),Xanthan gum(XG),Carrageenan(CA),and CMC formed a stronger network structure.Additionally,compared with SPIASG,the hybrid gel with added edible polysaccharides the water-holding capacity of SPI hybrid gels was relatively improved.In this study,a simple and easy method was obtained to significantly improve the gel properties of SPIASG,analyzed and compared the effectiveness of various polysaccharides to enhance its gel properties,and provided some ideas to improve the gel properties of SPI protein gels.

Effects of extrusion conditions on the physicochemical properties of soy protein/gluten composite

Soybean protein-gluten blend was extruded using a co-rotating twin-screw extruder.Effects of different extrusion conditions on the textural properties of extrudates were analyzed by central composite design through the evaluation of texturization index,water holding capacity,and hardness of extruded protein products.Extrusion process variables including feed moisture content(40%-60%),screw speed(12-20 Hz),extrusion temperature(120℃-180℃),and gluten content(16%-32%)were studied by the nonlinear regression equations analysis.The extrusion process was also optimized using response surface methodology(RSM).The influence of moisture content on the hardness of extrudate was the most significant.The optimized results,including feed moisture content,extrusion temperature,screw speed and gluten content were 49.18%-50.15%,155.24℃-159.86℃,16.41-16.73 Hz,20.00%-20.03%,respectively.The microstructures of TISP products were analyzed by scanning electron microscopy(SEM)and the changes of protein molecules before and after extrusion were also analyzed by SDS-PAGE electrophoresis.

Rheological properties and fractal-rheology analysis of peanut protein isolate suspension

This study focuses on the non-linear rheological property and microstructure of peanut protein isolate(PPI)aggregation suspension.The impact of higher harmonics(I3 and I5)on fundamental stress wave during large amplitude oscillatory shear test was studied.Rheological test show that storage modulus G′and loss modulus G″increased with increasing PPI concentration.The non-linear viscoelastic properties of PPI suspension with different concentration were investigated.Using confocal laser-scanning microscopy method,this research explored the microstructure of PPI suspension as well as the fractal dimensions.The new critical strain indirect method combined with Wu-Morbidelli model to calculate the fractal dimension(2.9225)is very close to the actual fractal dimension(2.9206).Fourier Transform Rheology was adopted to get the new critical strain for fractal dimension calculation,which was proved to be feasible.

Rheological properties of peanut protein isolate aggregation suspension and acid-induced gel

The dynamic rheological properties of peanut protein isolate(PPI)suspension and acid-induced PPI gels were studied.In frequency sweep test,the storage modulus(G′)and the loss modulus(G″)of PPI aggregation suspensions at different concentrations increased with the increase of frequency.The steady state shear flow test showed that PPI aggregation suspension had a thinning behavior of the shear,and the image of steady shear curve fitted the Carreau model.After gel formation,acid-induced PPI gels showed a typical Type I behavior(strain thinning)in strain sweep test,meaning that PPI gel got easily broken down,and there was a very small opportunity for the protein molecules to re-establish the network.Compared with the strain sweep of PPI aggregation suspensions and gels,the range of the storage modulus existed a dramatic difference,which could get about tenfold.As the frequency increased,both elasticity and viscosity increased in frequency sweep test,which indicated that the frequency dependence of the storage modulus increased with the increase of concentration.

Effects of xanthan gum on the rheological properties of soy protein dispersion

This study focused on the effects of addition of xanthan gum(XG)on the rheological properties of soy protein isolate(SPI)solution.Three types of tests(steady shear test,strain sweep test,and frequency sweep test)were performed to figure out the influences of shear rate on the viscosity of the SPI-XG hybrid system,the effects of strain variable on the storage modulus of the hybrid system,and the effects of frequency on both the storage modulus and the loss modulus of the hybrid system,respectively.SPI-XG hybrid system showed more obvious shear-thinning properties compared to pure SPI and pure XG solution.Meanwhile,it was found that the critical point of hybrid system was highly related to the XG concentration.XG can postpone the critical point strain amplitude to a higher value,and the addition of XG can enhance the strain resistance of hybrid system.The concentration of XG influenced the viscoelastic frequency dependence of the hybrid system significantly and complicatedly.After the addition of XG,the correlation between G′and frequency changed from negative to positive.