Utilization of liquid waste from brandy production for vineyard fertilization and its effects on wine base quality parameters

<jats:p>Background: Sustainable agricultural development requires the production of safe foods with high nutritional and functional value, the rational use of natural resources, the preservation and enhancement of soil fertility, and the efficient recycling and utilization of industrial by-products. The present study investigated the application of vinasse, a liquid by-product of brandy production, as a liquid organic fertilizer in vineyards. An application methodology was developed, and its effects on grape yield and the quality parameters of wine base intended for brandy production were evaluated. Objective: The objective was to evaluate the effectiveness of vinasse (a liquid by-product of brandy production) as an organic liquid fertilizer for vineyard nutrition and to scientifically assess its impact on grape yield and the quality characteristics of wine base intended for brandy production. Methods: The research combined field experiments with laboratory analyses. Vinasse was applied at a rate of 120 t/ha using two different methods: Surface application through irrigation without dilution Application together with irrigation water after dilution Standardized methods were used to evaluate the physical, physicochemical, and agrochemical properties of the soil, as well as the quality parameters of wine base intended for brandy production, taking into account the chemical composition of grape berries. Results: Surface application of undiluted vinasse significantly reduced soluble salt content while increasing the availability of mobile nitrogen, phosphorus, and potassium in the soil (p ≤ 0.05). Consequently, soil agrochemical properties and fertility improved without compromising agroecological sustainability. This treatment also enhanced grape quality and improved the chemical characteristics of wine base intended for brandy production.  Conclusion: The results demonstrate that the application of vinasse improves the physical, physicochemical, and agrochemical properties of irrigated meadow-gray soils. Utilization of liquid waste from brandy production can contribute to the production of grape raw materials with enhanced biological value, thereby creating favorable conditions for the development of functional winemaking products and functional foods.  Novelty: This study provides targeted quantitative evidence on how specific surface application methodologies of brandy-derived vinasse optimize meadow-gray soil fertility parameters and selectively enhance the phenolic and ascorbic acid profiles of Rkatsiteli (Vitis vinifera L.) wine bases, establishing precise nutrient-yield-quality correlations for regional viticultural management. Keywords: Vinasse, brandy, wine base, organic fertilizer, agrochemical properties.</jats:p>