EFFECT OF SOLID CONTENT AND SUGAR COMBINATIONS ON THE QUALITY OF SOYMILK‐BASED YOGURT

A research to evaluate the effect of two levels of solids and two sugar combinations in the quality of a soymilk yogurt-type food was carried out. Yogurts were elaborated by inoculating lactic cultures (Lactobacillus dellbruckii spp. bulgaricus and Streptococcus salivarius spp. thermophilus) into soymilk with 8% and 11% solid levels and glucose/sucrose and glucose/fructose mixtures. Also, a control treatment with cow milk was prepared. Yogurts were analyzed after two days of preparation for their chemical (protein, lipids, titrable acidity and pH), physical (syneresis and viscosity) and sensory characteristics (quality and acceptability). Protein content of soymilk based yogurts ranged between 3.56 and 4.45 g/100 g. The higher titrable acidities (0.66% and 0.63% lactic acid) were shown by treatments with higher solids level, which also shown the lowest syneresis. All soymilk yogurts were yellowier than the control. The highest sensory acceptability was for the 8% solids treatment enriched with glucose and sucrose. PRACTICAL APPLICATIONS There are an increasing number of people suffering of lactose intolerance, which need an alternative product to milk. Besides, some people have adopted a strictly vegetarian way of life. Soymilk has been used for a long time by this part of the population; however, it usually has a beany flavor, which can cause some rejection among occidental consumers. A fermented product from soymilk, such as soymilk yogurt, may offer a good alternative for those people. In soymilk production it is necessary to carefully adjust the amount of solids and the sugar used in fermentation in order to obtain a well accepted commercial product. Soy yogurt could be used to formulate a number of different new products like desserts, high fiber yogurt, fruit-added yogurt and so on.