Nowadays much attention is paid to functional environmentally friendly products, issues of improving their safety without loss of quality. In this case, factors from initial quality to the final result, which depend on temperature, processing time, enzymatic activity of the raw material, and especially the preparation technology of the product, variety, and culture, are of great importance. Employees of VNIIOOB, a branch of the FSBII “PAFSC RAS” in the Astrakhan Region, set a goal to study the effect of storage and processing of pumpkin fruits on the change in the content of basic chemicals depending on the variety. The task included the selection of varieties of breeding VNIIOOB suitable for processing. Studies of Annushka and Kroshka pumpkin varieties that affect the accumulation of nitrates in fruits during storage showed that after 90 days their quantity decreased by 5.2 mg / kg in the Kroshka variety and 3.5 mg / kg in the Annushka variety, but did not exceed the maximum permissible concentration (200 mg / kg), and was 1.9–2.2 times lower, which indicates the safety of the product. A high content of ascorbic acid, carotene and pectin, characterizing pumpkin fruits as a dietary product, was noted. The experiments on changing the main chemicals during processing of pumpkin fruits (pickling) showed that after passing through the fermentation process (3 months of storage), the nitrate level decreased to the initial level in the Kroshka variety by 32.6 mg / kg, in the Annushka variety by 33.3 mg / kg or 1.5–1.7 times less than the maximum permissible concentration. It was found that due to the diffusion of sugar from the marinade into the fruit, its amount slightly increased with the predominance of monosugars. The low nitrate content and the predominance of monosaccharides allow pickled pumpkin to be attributed to dietary functional products.