Study On Gelling Characteristics Of Tremella Polysaccharide And Production Process Of Tremella Soft Sweets

In this paper,the polysaccharides(TPS)from Tremella fuciformis were extracted by microwave method,and the optimal extraction process parameters were optimized.The rheological and gelling properties of the TPS,and TPS-gellan mixtures were studied with food rheological measurement and other methods.This provided a basis for the application of TPS in the food industry.On this basis,the fabrication process of Tremella soft sweets was studied by texture analysis and sensory evaluation,which also provided the theoretical guidance for the application of food rheology and texture analysis methods in the industrial production of soft sweets.The specific content and results of this paper were as follows:1.Optimization of microwave extraction of tremella polysaccharide(TPS)The best process for the extraction of Tremella polysaccharides by microwave method was determined by single factor test and orthogonal test: when the liquid to material ratio was 50:1(mL/g),the particle size was 120 mesh,the microwave power was 400 W,and the microwave time was 2.0 h,the highest extraction rate of Tremella polysaccharide was(33.25±0.14)%.2.Study on the rheological properties of tremella Polysaccharide and TPS-gellan mixtures(1)The static rheological results showed that the apparent viscosity of TPS decreased with the increasing of shear rate,and the TPS acted as a pseudoplastic fluid in distilled water,the viscosity exponentially increased when its concentration increased,and the viscosity decreased with negative exponent as the temperature increased.The dynamic modulus increased with increasing frequency,and the TPS solution could form a weak gel structure in the high-frequency region.(2)The static rheological results showed that the apparent viscosity of TPS-gellan decreased with the increasing of shear rate,showing the properties of pseudoplastic fluid.The viscosity had a positive exponential relationship with the increasing of the proportion of TPS.Dynamic rheological results showed that TPS could improve the viscoelasticity and fluidity of the TPS-gellan mixtures.The thixotropy results showed that the TPS-gellan mixtures was a thixotropic system,and the addition of TPS could improve the thixotropic properties of gellan gum.3.Study on the gelling properties of tremella polysaccharide and TPS-gellan mixturesGel property was one of the important characteristics of gelling agents.The gelling properties of TPS and TPS-gellan mixtures directly affected their application in food.In this study,the texture characteristics of the gel were used as the evaluation criteria.It was found that when the concentration of TPS reached 20 mg/mL,a weak gel structure began to form.With the increasing of the concentration of TPS,the hardness and chewiness of the gel improved,and the springiness decreased first and then increased.The gel strength and hardness of the TPS-gellan mixture gels increased with the increasing of the proportion of the gellan gum(GG).In addition,the springiness and viscosity of each ratio of TPS-gellan mixture gels was greater than that of gellan gel used alone,when the compounding ratio was 1.6% TPS-0.4% GG,1.2% TPS-0.8% GG,0.8% TPS-1.2% GG and 0.4% TPS-1.6% GG,the gel springiness values was 28.15%,35.77%,38.08%,and 43.87%,higher than 0.4%,0.8%,1.2%,and 1.6% gellan gel.Combined with the analysis of Fourier-transform infrared(FT-IR)spectrum and cryogenic scanning electron microscopy(cryoSEM),it was indicated that there was an interaction between gellan gum and tremella fuciformis polysaccharides in the compound system,and a gel network structure was formed.4.Optimization of the production process of tremella soft sweetsThrough the optimization of single factor and orthogonal test,the hardness and sensory score of tremella soft sweets were used as indicators to obtain the best formula of the production process of tremella soft sweets: 1.6% of gellan gum,20% of sugar,0.5% of citric acid,and 2.0% of salt.The tremella soft sweets prepared under these conditions had unique taste,attractive flavor and good chewiness and springiness.