engleski

Effects of concentration and temperature on rheological properties of some hydrocolloids

Natural and synthetic hydrocolloids, or gums, find significant use in the food industry in controlling the rheological properties of many modern convenience food products. They are normally used in low concentrations, ranging from 0.05%, or less, to about 5%, and do not usually contribute to the nutritional value, taste, or aroma of the finished product. In this study, flow behaviour of six selected hydrocolloids (carrageenan, carboxymethylcellulose, guar gum and three type of pectins) was evaluated using rotational viscosimeter at selected concentrations (0.1-1%, depending on the type of hydrocolloid) at low temperatures. Dispersions of all hydrocolloids had pseudoplastic behaviour, at all given concentration. Ostwald-de Waele's model was used to evaluate their rheological properties. The temperature effect on the apparent viscosity followed an Arrhenius-type relationship.

hydrocolloids; rheological properties; low temperatures

nije evidentirano