The objective of the paper was assessment of the selected qualities of carrot from retailer's shops, organic and traditional food shops in Krakow. The following quality parameters of the fruit pulp were investigated: content of extract, sugars, polyphenols, nitrite, flavonoids, beta-carotene, colour, and antioxidant activity. The investigation shows that the content of nitrogen (V) in the samples of carrot from traditional cultivations was higher than in case of carrot from organic crops, and in case of a sample from traditional cultivation it exceeds the admissible norms. However, the research which was carried out provides no justification for the statement that the content of nitrate (III) depends on the production system of carrot. The research on the content of polyphenols, flavonoids and antioxidant activity of juice proved the increased antioxidant ability of carrot that was traditionally cultivated with reference to carrot cultivated organically. However, the differences were not statistically confirmed. Beta-carotene content in all samples was comparable regardless the cultivation system. Content of extracts, total carbohydrates and sucrose was significantly higher for carrot from traditional crops than for eco-carrot.
The aim of the experiment was to determine the impact of UV-C stimulation of tubers, immersion of potato sticks in water, and a frying fat type on the content of fat in dry mass of French fries. Tests were carried out on Innovator tubers which is one of the most often used cultivator in production of French fries by the European and Polish companies. Radiation of potato tubers with ultraviolet in band C were performed with the use of the original stand for stimulation of biological material with electro-magnetic radiation. A statistical analysis of the obtained results of tests indicates that stimulation of tubers and a type of frying fat had a statistically significant impact on the fat content in dry mass of French fries.