| In this study, rheology analysis and texture analysis were used to study the relationship between physical properties index with stability and organoleptic quality of whipped cream. And on this basis, building mathematical model to quickly and accurately judge the organoleptic quality and stability of whipped cream through the multivariate analysis(factor analysis, cluster analysis and discriminant analysis).Compositions, organoleptic properties, rheology and texture of three commercial whipped cream with significant difference in stability were analyzed. Static rheological test showed that whipped cream was thixotropic and pseudoplastic, while dynamic rheological test showed gellike properties. By decreasing tendency of G* in the latter test, while the flow activation energy of first and second sample which were less stable, respectively, with a distinctive critical temperature of 15 ℃. In both oscillation time scanning and oscillation frequency scanning tests, the third sample, with the highest G’ and lowest tanδ(<0.3), was demonstrated with highest proportion in elastic component. Combined with the organoleptic evaluation and storage experiment with rheological analysis, the result showed that G’ can effectively characterize the stability and both area of thixotropic loop and yield stress could characterize hardness and softness of whipped cream. In addition, greasiness and mouth feel were closely related to |?G’| and rate of recovery, the storage stabilities were closely related to creep compliance Je and E.To investigate how to use the rheological properties to quickly, accurately estimate the stability of whipped cream, I select eight rheological properties that were significantly correlated to stability(P < 0.05) by the correlation analysis. The stability of 10 commercially available whipped cream were analyzed using factor analysis(FA) and cluster analysis(CA). The FA results indicated that there are three main factors "main stability factor", "thixotropic loop factor" and "strain equilibrium factors", and time scanning G ’, the area of thixotropic loop S and strain equilibrium r is important to the stability of whipped cream. In addition, the total factor score expression is TFS=f1×0.38476+f2×0.25671+ f3×0.22858. The TFS ranking reflected the diffidence of the stability of whipped cream. The CA results showed that 10 whipped cream could be classified into three clusters. The first kind had 7 samples, namely, 5, 6, 1, 8, 9, 10 and 2. NO.3 and NO.4 were classified into a cluster and NO.7 was classified into a cluster.To get eight rheological properties two structure properties index that were signify-cantly correlated to stability(P < 0.05) by the correlation analysis from 10 kinds of commercially available whipped cream. Factor analysis showed that the dynamic yield stress and apparent viscosity, as well as the quality and structure index consistency an d viscosity index were the key to whipped cream quality. According to the three main factor variance contribution,I get a total factor score TFS =f1×0.4055+ f2×0.3291+ f3×0.26542. Clustering analysis showed that 10 samples can be divided into four types, the first kind of gathered samples of 7 and 8;The second class gathered samples of 3 and 4;The third class brought together 10 and 2 samples;The fourth class gathered all the remaining samples. The CA results can get canonical discriminant function Y4 = 0.015249×dynamic yield stress-0.000344×consistency +0.005978×index of viscosity +0.582271×apparent viscosity +1.380 and bayes model Y5=0.032×dynamic yield stress-0.020×consistency +0.033×index of viscosity +1.613×apparent viscosity-24.400 and Y6=-0.062×dynamic yield stress+0.022×consistency-0.004×index of viscosity-1.977×apparen-t viscosity-32.908 to accurately and quantitative judge the organoleptic quality of wh-ipped cream. |
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