Potato dry matter

The dry matter content in potatoes is expressed as a percentage of the total tuber weight. Since starch accounts for 70–80% of all dry matter, an indirect method of determining specific gravity by weighing tubers in water and air is often used for assessment. The following classification is adopted: low content (less than 22%), medium (22–25%), and high (more than 25%); varieties with high levels of this indicator are preferred for the production of chips and french fries.

High dry matter content (above 18–20%) contributes to better boiling properties, but makes tubers more sensitive to mechanical damage and bruising. The indicator is influenced by agronomic factors: an excess of nitrogen and chloride-containing fertilizers at late growth stages reduces dry matter accumulation, while magnesium deficiency and drought during the tuberization period negatively affect the final product quality.