RHEOLOGICAL CHARACTERIZATION OF COFFEE-FLAVORED YOGURT WITH DIFFERENT TYPES OF THICKENER Caracterização reológica de iogurte sabor café com diferentes tipos de espessante.
Year: 2011
Type: article
Abstract: Yogurt is a functional food that has great demand due to the consumer’s search for a healthier diet. In order to expand the consumer market of this product, many fl avors are available, satisfying the most varied preferences. Besides the taste attribute, consistency and viscosity of yogurt are some of the main factors involved in product quality and acceptance. Therefore, this work is a study of the infl uence of concentration of thickener in coffee-fl avored yogurt. The thickener agent used was gelatin. The rheological behavior (fl ow and viscosity curves) of yogurts with and without addition of gelatin was compared with commercial yogurt, which contains another type of thickener (locust bean gum) in its formulation. The fl ow and viscosity curves were obtained from rotational rheometer Thermo Haake Mars, with a range of shear rate from 0.02 to 100 s-1 (rising curve) and 100 to 0.02 s-1 (descendent curve) at a total time of 20 minutes. Hysteresis was determined as the area between the curves and adjusted to the models of Bingham, Casson, Herschel-Bulkley and Ostwald-de-Waele. Were also carried out tests of thixotropy, by measuring the viscosity as a function of time at a constant rate of 100 s-1 for 10 minutes. These curves were adjusted by the Weltman model. All samples showed pseudoplastic and thixotropic behavior. The Herschel-Bulkley model was the best fi t to the three samples tested. The Weltman’s model well described the thixotropy tests, except for the sample of commercial yogurt. The use of gelatin as a thickener showed protective character, reducing the structural break of the gel.
Source: Alimentos e Nutrição
Language: Portuguese
Subfield: Food Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W142263268