Study of the composition of potatoes by agronomic traits determining its suitability for industrial processing

The study of biochemical quality indicators of 26 new potato hybrids was carried out in order to determine the ones mostly suitable for processing into starch and potato products and for use as table variety. An express method was used to determine dry matter (DM), Evers method was used to determine the total starch content of tubers, the polarimetric method and a glucometer test were used to determine reducing sugars, glycoalkaloids and inorganic phosphorus were determined by spectrophotometric method. There have been selected 5 hybrids suitable for industrial processing and as a source material for breeding. One potato hybrid with 25,06 % content of DM, more than 18,22 % of starch met the requirements for potatoes used for processing into starch and starch products; another potato hybrid can be recommended for the production of fried potato products according to the parameters: DM – 22.40 % starch – 16.18 %, reducing sugars – 0.23 %, glycoalkaloids – 62,0 mg/kg. Three of the studied hybrids with the content of DM of more than 22 %, starch not less than 16%, reducing sugars 0.2-0.4 % and glycoalkaloids 60-126 mg / kg may be used for the production of other types of potato products. The rest of the hybrids can only be recommended for use as table potatoes. The relationship between indicators affecting the quality of potato products has been revealed. Correlations were established between the mass fractions of: dry matter and starch in the tuber (r = 0.98) – high correlation; reducing sugars and glycoalkaloids (r = 0.68); tuber dry matter and glycoalkaloids (r = 0.59); dry matter and glucose (r = -0.61); starch and glucose (r = -0.58) – average correlations. It has been established that the mass fraction of reducing sugars and the direction of rotation of the plane of polarization of light by sugars change non-linearly under different temperature conditions of sample storage.