Given the lack of meat raw materials and the desire to reduce the cost of production the availability of alternative sources of protein are important for the meat industry. One solution to this problem is to find ways to improve the functional and technological parameters and structural-mechanical properties of soy protein.

We consider the use of silica (SiO₂) type A 300 with a particle size (60%) of about 10 nm as the main structuring additives in this work.

After analyzing protein preparations markets we selected the following plant origin proteins: soy isolate "Pro-Vo 500 U" (hereinafter – isolate); soy concentrate "Pro-Vo KM" (hereinafter – concentrate); soy texturate "Pro-Vo Tex PU 35" (hereinafter – texturate); concentrated soy protein GS8100 (hereinafter – protein).

To confirm or refute technological data regarding the degree hydration of protein preparations there were selected next degrees of hydration – 1: 2, 1: 4 and 1: 6. Hydration was performed as recommended by manufacturers and while measuring the water content, ability to bind moisture and pH value.

The next step was to study the influence of food additive silica (E551) on the functional and technological parameters of protein and on the stabilization of system.

The results of studies with regard to the rational value of ability to bind moisture by 85%, indicated that the addition of silica in amount of 0,3% increases the value of ability to bind moisture on average by 3,6 ± 0,1%. This supports the hypothesis that the silicon nanoparticles can join the peptides and proteins. The largest increase ability to bind moisture is fixed for isolate and concentrate and protein showed decline of hydration. This indicates that for isolate and concentrate the use of higher hydration level is logical.

Presented protein preparations are used in the manufacture of boiled sausages and sausages. Their production technology involves heat treatment with 72 ^оС temperature in the center of the product. It was therefore investigated the change of ability to bind moisture by hydrated protein preparations after heat treatment with the addition of silica and without the addition silica in the amount of 0,3%  gel weight.

Research results, indicating ability to bind moisture by hydrated proteins after heat treatment, suggest that the introduction of silica into the soy concentrate and isolate in the same amount increases ability to bind moisture by 6,3%. This is almost twice better to the average value for the hydrated protein without heat treatment. This demonstrates the expediency of introduction E551 food additive in soy protein preparations.

Effective viscosity of protein preparations with silica increases compared to protein preparations without silica. This indicates positive effect of additive E551 on the structural-mechanical properties of hydrated proteins.

Research results of indicators emulsion stability and emulsifying ability to soy isolate and concentrate indicate increasing these parameters in samples with silica in the hydration of 1: 4 and 1: 6 by 6% and 9% respectively. For protein it is the opposite: when introduced the silica decreases emulsion stability and emulsifying capacity, the product is stratified. This is caused by destruction of fat-protein-water system, which is associated with a specific chemical composition of the drug.

In this work we investigated the functional properties of protein preparations of plant origin: soy isolate "Pro-Vo 500 U", soy concentrate "Pro-Vo KM", soy texturate "Pro-Vo Tex PU 35" and soy protein GS8100. It was found that the highest functional and technological indicators showed soy isolate "Pro-Vo 500 U" and soy concentrate "Pro-Vo KM", which are synergists with the food additive E551. Further work in the direction of formation food compositions for meat products, are being performed with the use of silica (SiO2) and soy concentrates and soy isolates.

Key words: protein preparations, silica, functional indicators, structural-mechanical properties, heat treatment.