Rheological Properties and Texture of Yoghurts When Oat-Maltodextrin is Used as a Fat Substitute

Abstract

Yoghurts were produced from cow's milk containing 1, 2 and 3 kg milk fat/100 kg or 1, 2 and 3kg of oat-maltodextrin/100 kg (maltodextrin included 5 kg b-glucan/100 kg). Non-fat yoghurt, without the addition of maltodextrin, was used as a control product. The yoghurts were estimated for sensory properties and using instrumental texture profile analysis (TPA) and rheological investigations, which had to set flow curves and their description by the Ostwald de Waele and Casson models; counting apparent viscosity were also done. Replacing milk fat with maltodextrin in yoghurts does not show significant differences in the sensory analysis, rheological properties and most of the texture parameters. The addition of milk fat in the amount of 1 kg/100 kg or maltodextrin in 2 kg/100 kg caused an increase in apparent viscosity of yoghurts. The addition of oat-maltodextrin caused a decrease in consistency index value and a deviation from the Newtonian flow and yield stress, similar to the effects caused by adding milk fat. No relationship between the results of the sensory evaluation, the instrumental texture parameters and rheological properties, especially in yoghurts containing milk fat, were shown