Efecto de tres concentraciones de grasa y dos niveles de acidez en un yogur estilo griego

Greek style yogurt is milk product of the fermentation of lactic acid bacteria Streptococcus thermophilus and Lactobacillus delbrueckii, which is concentrated after fermentation to increase the protein content to a minimum of 5.6 percent. The objective of this study was to determine the effect of three fat concentrations (0.5, 1.0 and 2 %) and two levels of acidity (0.9 and 1.2 % Titratable acidTA) on physicochemical and sensory properties of Greek style yogurt. The experimental design was a randomized complete block with a factorial arrangement 3x2 and repeated measures in time (0 and 30 days), for a total of 36 experimental units. The physicochemical characteristics evaluated were color, texture, protein, TA, fat, purge, performance and total coliform counts performed. The sensory hedonic responses were evaluated by 35 yogurt consumers, evaluating appearance, acidity, aroma, taste, viscosity and general acceptance. A paired preference analysis compared the best treatments. The percentage of fat and the acidity level variables influenced physicochemical and sensory properties of the yogurt. The 2% fat and TA 0.9 yogurt was the most preferred. The 0.9 % TA treatments were less firm in texture analysis and present a lower protein content, as well an increased the percentage of purge and less performance in the yogurt.