RHEOLOGICAL, TEXTURAL, COLOR AND PHYSICO-CHEMICAL PROPERTIES OF SOME YOGURT PRODUCTS FROM THE SPANISH MARKET

Abstract

Yogurt is nowadays one of the most consumed fermented milk products in the world due to its benefits for the human body. The purpose of this work is to study the rheological, textural and color aspects of different types of yogurts from the Spanish market. For this study, two types of yogurt, blank yogurt and fruit yogurt respectively were selected; five samples for each type, each one with different concentration of total soluble content, fat content, protein and sugar content were analyzed. The study shows the existence of some correlations between some physico-chemical and textural parameters, so the highest adhesiveness and cohesiveness are reached by the sample with 10% fats, while the tension parameter is the highest for the sample with the lowest concentration of sugars, and the highest firmness is reached in the sample with the lowest concentration of fats. The color parameters are influenced by the presence of the food colorants, and their nature. The PCA made provides some explanation on the two components of 100% of the total variance and it was observed that the 2 types of yogurt are situated in different groups. The analysis of variance (ANOVA) conducted revealed that considering that a higher value of F-ratio means a more noticeable effect of the factor (type of yogurt) in a variable, the parameters  tone and a^* were  more distinguished by the type of yogurt.