Over the past two decades, people worldwide, including Russia, have been placing great emphasis on ensuring the healthy nutrition of the population. Our country developed quite an extensive legal and regulatory framework to address the problem of ensuring healthy nutrition: Federal Law No. 29-FZ "On the Food Quality and Safety"; State Policy of the Russian Federation in the field of Healthy Nutrition; Strategy on the improvement of the quality of food products in the Russian Federation until 2030, Food Security Doctrine of the Russian Federation [1-4].
Thus, the Doctrine adopted in January 2020 [4] pays much attention to ensuring the food physical and economic safety due to domestic products, as well as import substitution of both finished products and ingredients for their manufacture.
This mainly applies to soft drinks which include a large extend of such drinks as Cola, Fanta, etc. Imported ingredients prevail in their recipes, which challenges solving the issue of import substitution.
In this regard, this problem in the market of soft drinks can be solved by designing, introducing into production, and selling traditional domestic beverages that meet the needs of not only the Russian market but also the markets of many countries of the former Soviet Union and beyond. These drinks include bread kvass.
Kvass is a soft drink with a maximum ethanol volume ratio of 1.2%, made as a result of incomplete alcoholic or alcoholic and lactic acid fermentation of the wort. The word "kvass" is certainly of Russian origin and means "sour drink". The first prototypes, representing a cross between kvass and beer, appeared in Egypt in the VI millennium BC. Hippocrates, Herodotus, and Pliny the Elder described beverages similar to kvass in their works. Fruit kvass was also known in Babylon, although it was not widespread in Mesopotamia [5].
The Slavs have known kvass for more than a thousand years. The Eastern Slavs knew its recipes long before the formation of the Kievan Rus'. The first mention of kvass in Russian written sources dates back to 989 when Vladimir I Svyatoslavovich, the Prince of Kyiv, converted his lieges to Christianity.