Study On Rheological Properties Of Chocolate Pastes Of Cocoa Butter Replacers

In this study,the rheological properties of cocoa butter substitute based chocolate were studied.Viscosity and yield stress were chosen as rheological properties to explore the effects of different ingredients on them.The rheological properties of different formulations were different.The study can provide effective theoretical basis and experimental data for the generation of cocoa butter chocolate production,processing quality control.(1)All the samples tested yield stress.With the shear rate increases,the shear stress linearly upward trend.All samples belong to non-Newtonian fluid.With the increase of shear rate,the viscosity becomes a decreasing trend,which is the phenomenon of shear thinning,which belongs to the pseudo plastic flow in non-Newtonian fluid.In accordance with the Herschel-Bulkley equation,and the correlation coefficients are greater than 0.95.(2)The bulk equation was y = 2903.263-0.583791X1 + 0.170619X2 + 225.979X3,and the regression equation was obtained by using the whole milk powder and skim milk powder and PGPR as the variable.R2 = 0.9686,it is proved that the model has high fitting degree,and the model is analyzed by variance,P <0.01,which shows that the model is effective.The effect of the addition amount of whole milk powder on the viscosity is not significant,the amount of skim milk powder on the viscosity of the significant impact,and different ratio of whole milk powder and skim milk powder on the sample viscosity and yield stress,so the whole milk powder And skimmed milk powder with white chocolate viscosity of the existence of interaction,but the difference between the formula can’t be carried out through the sensory evaluation test intuitive evaluation.(3)For dark chocolate,the regression model is y = 7404.34-5.62683X1-6.3494X2 with the addition of two kinds of cocoa powder as the independent variable and the viscosity as the dependent variable.The regression model R2 = 0.9669,which proves that the model has a high degree of fit.The variance analysis of the model is shown in the table,P <0.05,and the model is significant,indicating that the model is effective.The regression model shows that the addition of different cocoa powder has a significant effect on the viscosity of the sample.(4)For the three additives,with the increase of Revel C content,the viscosity of chocolate pulp is not significant at 40 ℃,the yield stress is the first to reduce and then increase the trend,so according to the required product traits,Reasonably select the amount of Revel C added.The addition of PGPR can make the different components within the cocoa butter chocolate have good homogeneity,and the prepared chocolate can’t have the need of temperature adjustment can have a good stability of the crystal structure,can effectively slow down the phenomenon of chocolate frost.There was a positive correlation between the addition of lecithin and the yield stress and viscosity of the sample.