Nuclear magnetic resonance (NMR) spectroscopy is an innovative method for wine analysis. Every grapevine variety has a unique structural formula, which can be considered as the genetic fingerprint of the plant. This specificity appears in the composition of the final product (wine). In the present study, the originality of Hungarian wines was investigated with ¹H NMR-spectroscopy considering 861 wine samples of four varieties (Cabernet Sauvignon, Blaufränkisch, Merlot, and Pinot Noir) that were collected from two wine regions (Villány, Eger) in 2015 and 2016. The aim of our analysis was to classify these varieties and region and to select the most important traits from the observed 22 ones (alcohols, sugars, acids, decomposition products, biogene amines, polyphenols, fermentation compounds, etc.) in order to detect their effect in the identification. From the tested four classification methods—linear discriminant analysis (LDA), neural networks (NN), support vector machines (SVM), and random forest (RF)—the last two were the most successful according to their accuracy. Based on 1000 runs for each, we report the classification results and show that NMR analysis completed with machine learning methods such as SVM or RF might be a successfully applicable approach for wine identification.

Protein-based clarification agents were tested to clarify Chardonnay grape musts during sedimentation. The experiments were conducted in the Etyek–Buda Wine Region in Northwest Hungary over four vintages between 2020 and 2023. The performance of the treatment agents was influenced by several factors, such as the composition of the grape must (the absolute concentration and the relative ratio of phenolic compounds) which varied with the vintage characteristics, the physiological and phenolic ripeness of the grapes, and the composition of the clarifying agents itself. Recent investigations show that fully ripe fruit juices can be clarified more effectively, and the effectiveness increases when different types of clarification agents are combined with the plant proteins, e.g., PVPP greatly facilitates the removal of phenolic compounds. The tested plant protein-based clarification agents did not influence the YAN source of the grape musts before fermentation. Our investigations proved an effective impact of these preparations even during the first steps of wine technology. Sensory properties and chemical stability are improved by decreasing the polyphenol content before fermentation, and, besides the good technological effects, wines treated with plant protein agents can be included in the vegan diet.

Due to climate change, the sugar content of grapes in Hungary has increased to such an extent that the high alcohol content alone can make wines disharmonious. In most vintages, this phenomenon is only a problem for early-ripening varieties. In order to prevent and treat this difficulty, we have carried out experiments in grape canopy management for four years with the aim of delaying ripening and thus reducing the sugar content of the grapes. The experiments were set up on an early (Pinot noir) and a late (Welshriesling) variety; two treatments (leaf removal—LR and short topping—ST) were applied and compared to untreated controls in the years 2019–2022. Our results showed that grape juice sugar yield was significantly reduced in all four years and for both cultivars, while the other measured parameters (yield, acidity, pH, and Botrytis infection) were only lightly affected.

Due to climate change, the sugar content of grapes in Hungary has increased so the high alcohol content alone can make wines disharmonious. In most vintages, this phenomenon is only a problem for early-ripening varieties. In order to prevent and treat this difficulty, we have been carrying out experiments in grape canopy management for four years with the aim of delaying ripening and thus reducing the sugar content of the grapes. The experiments were set up on an early (Pinot noir) and a late (Welshriesling) variety; two treatments (leaf re-moval - LR and short topping - ST) were applied and compared to untreated control in the years 2019-2022. Our results showed that must sugar yield was significantly reduced in all four years and for both of cultivars, while the other measured parameters (yield, acidity, pH, Botrytis infection) were not or lightly affected.

The study compared the effects of conventional and vegan processing aids in the clarification of must, focusing on the phenolic and sensory characteristics of must and wine. The hypothesis was that plant protein could provide results similar to those of conventional aids containing proteins of animal origin, especially in aromatic grapes, where hyperoxidation is avoided. Conducted in 2024 in Etyek-Buda, Hungary, the initial trials subjected the Irsai Olivér grape must to gravity sedimentation with various agents. Vegan processing aids, notably the combination of pea protein and chitin-glucan, showed a gentle impact on the assimilable nitrogen content and a similar reduction in turbidity to those with animal proteins. Nitrogen flotation trials compared gelatin and the vegan alternative (a combination of pea protein and chitin–glucan) in Irsai Olivér and Chardonnay must clarification. The removal of phenolic substances was monitored using the Folin–Ciocalteu method, the acid butanol assay, and the vanillin assay. In addition, nitrogen levels were evaluated before and after the flotation experiments. The plant-based processing aid effectively improved the sensory quality of Irsai Olivér. However, the gelatin-treated Chardonnay was fresher and less bitter than the vegan option, which was less balanced and more bitter with weaker aroma and flavor.