Pretreatment of soriz grains by soaking for use in the food industry

Abstract

Soryz grains are a cereal crop adapted to the climatic conditions specific to the Republic of Moldova. In addition to high productivity even in drought conditions, soryz has an appreciable

chemical composition, especially for the content of carbohydrates (especially starch), followed by proteins. In this context, taking into account the current trends of obtaining innovative food products by substituting proteins of animal origin with those of vegetable origin, the respective

cereal could be an indicated raw material. The purpose of this work was to highlight the properties of the soryz starch and proteins through soaking processes in water, for their subsequent use in the manufacture of meat analogues. The obtained results showed an evolution of the grains hydration degree as a function of time followed by temperature and have a complex character. During the hydration process, it was divided into three consecutive phases: the phase of very rapid increase in the hydration degree that lasts up to 2.0 hours, the stabilization phase, responsible for the hydration of proteins and the phase of linear growth, when the constant increasing rate of the soriz grains hydration degree is reached. The rate of water absorption over time is initially quite high, then decreases continuously and approaches equilibrium. The rate of hydration was obviously faster in the first 9 hours. The impact of temperature on the hydration process is obvious and quite defined, especially in the second

phase of hydration, the increase in the hydration medium temperature is directly proportional to the hydration degree of soryz grains. The values of the Peleg model constants, the K1 and K2, were depending on the temperature, being inversely proportional to the temperature, results highlighted for the temperature of 40, 45 and 50 ⁰C. The results obtained for the water diffusion coefficient in the soryz grains showed a linear increase with the increase in temperature up to 50° C, and decreases with the subsequent increase in the temperature of the hydration medium. This decrease may be a consequence of the processes of starch granule gelatinization and protein

denaturation, which modify the capillary structure of the grains and reduce the diffusion rate. The pretreatment of soryz grains by hydration, implicitly knowing the optimal conditions of

the respective process, predicts the transformation of this grain into a raw material of plant origin with the potential to define the characteristics of meat analogs, namely, their texture properties.