The whey is a product with high nutritional value, but it is too wasted. In this sense, this study aims to evaluate the physicochemical and rheological properties of goat whey. Content of total protein, lactose, fat, ash, total solids, humidity, pH and density of goat whey were determined. The whey rheological behavior was evaluated in different conditions of temperature and share rate. Two rheological models were used to fit the behavior of the goat whey and the activation energy was determined by Arrhenius equation. The characterization of goat whey showed satisfactory results. The increase in temperature resulted in a decrease of shear stress and apparent viscosity of goat whey, while the reverse was observed for strain rate increased. Ostwald-de-Waelle model presented a satisfactory arrangement with R² above 0.99 for all temperatures studied. The goat whey presented behavior index larger than 1, indicating that this is a dilatant fluid.
This study contributes in the existing literature about physicochemical properties of dairy products, focusing in the physicochemical and rheological properties of goat whey. Up to now, nothing was discussed about that. The study also documents that the goat whey is a dilatant fluid with small effect of temperature on viscosity.
This study received no specific financial support.
The authors declare that they have no competing interests.
The authors are grateful to National Council for Scientific and Technological Development (CNPQ) for its financial support and the Post-Graduation Program in Chemical Engineering (PPGEQ) from Federal University of Rio Grande do Norte (UFRN) by encouraging the research.