Rheological structure assessment of the plant alternative to yoghurt

Federal State Educational Institution of Higher Education “Kaliningrad State Technical University (KSTU)”, Kaliningrad, Russia

^* Corresponding author: marina.alshevskaya@klgtu.ru

Abstract

The growth in the number of people suffering from milk components intolerance implies the creation of their plant alternatives, corresponding in organoleptic characteristics, nutritional and biological values, but not having milk allergens. Therefore, development and study of the rheological properties of plant analogues of dairy products is relevant. The article discusses the structural and mechanical parameters of fermented plant products, from oatmeal powder, sunflower protein and with the use of starter cultures Streptococcus salivarius subsp. termophilus and Lactobacillus delbrueckii subsp. bulgaricus, depending on the mass fraction of pectin structurant and its shelf life. It is shown that, by the nature of the flow, the curves obtained refer to pseudoplastic liquids. It has been established that the destruction of the structure of the fermented plant product, and hence the decrease in effective viscosity, occurs in two stages: avalanche-like - at a shear rate of 5 to 24 s^-1; from 24 s^-1 and further - with a damping speed relative to the beginning of destruction. The regression dependence of the effective viscosity change on the shear rate and pectin concentration has been calculated. It has been found that with an increase in the storage time of the samples, their hardness increases up to the seventh day. After that this indicator decreases, which characterizes gradual destruction of their structure. The hardness work, the adhesiveness, the adhesive force and the resilience of prototypes have been determined. The obtained research results correlate with the studies conducted in the field of rheological characteristics of fermented milk products.