[Juices in a healthy diet: recommendations for consumption based on chemical composition data]

Juices from fruits and vegetables show a complex composition, they contain several hundred different substances. In addition to water and common metabolites such as carbohydrates, juices contain organic acids, minerals and trace elements, vitamins, polyphenolic and other biologically active compounds. Moreover, each type of juice is characterized by a unique set of natural compounds and is able to contribute to providing the human body with micronutrients. The study and analysis of the nutrient composition of commercially produced juices, which are currently the most consumed by the population, contributes to understanding the place of juices in healthy nutrition and is intended to contribute to the development of relevant recommendations for their use. The purpose of the research was to evaluate their nutritional density and nutritional value based on the analysis of published data on the nutrient composition of juices, and then offer recommendations on the use of juices in healthy nutrition. Material and methods. The analysis of nutrient profiles of ten popular types of juices presented on the market of the Russian Federation (apple, orange, grapefruit, grape, tomato, pomegranate, pineapple, carrot, cherry, peach) was carried out. Nutritional density indices (NDI) were calculated as the degree of satisfaction of a person's need for a particular nutrient when filling the calorie value of the diet (2500 kcal) only with this product. The integral score characterizing the degree of the juice compliance with an optimally balanced daily diet, taking into account the energy content, which provides 5% of energy, was also calculated. Results. NDI and the integral score of various types of juices show that juices have a high nutritional value and can make a significant contribution to the intake of some nutrients and bioactive compounds. The most important substances from juices are polyphenolic compounds (flavonoids, phenolic acids) and carotenoids (β-carotene, lycopene). All juices also contain significant level of potassium and magnesium, and they can serve a source of some vitamins and minerals (depending on the individual nutrient profile): citrus juices are the source of vitamin C and folates, pineapple - of manganese, vitamin C and B vitamins, apple - chromium, grape - molybdenum, iron and chromium, pomegranate - copper and tannins, cherry - iron, copper and pantothenic acid; vegetable juices, such as tomato and carrot juices, contain a wide range of essential micronutrients. Juices with pulp and juices without clarification can be a source of pectins and dietary fiber. Modeling of juice rotation in the diet shows that in this case, 75% of the nutrients (from 32 studied) will have a NDI1, i.e. provide a meaningful intake with juice. Conclusion. The characteristic features for each type of juice regarding the content of vitamins, minerals and other biologically active compounds should be taken into account to assess the place of juices in healthy nutrition and develop modern recommendations for their consumption. Such recommendations include alternating different types of juices in the diet, as well as, if necessary, the choice of certain juices to include in the diet, depending on the individual's nutritional needs.