Grape maceration is essential in modulating the quality of Tokaj wines. The aim of this research was to analyse the effect of two maceration practices—one utilizing the application of a Saccharomyces cerevisiae culture and the other being maceration without a yeast culture in experimental Lipovina (Vitis vinifera L.) white wine from the Slovak part of the Tokaj region. Multiple factor analysis was used for the examination of wine quality regarding the formation of biogenic amines (BAs), and chemical, microbial and sensory variables were analysed over three months of wine production. The formation of bioactive components in wine was affected by maceration and maceration with the addition of a yeast culture, which resulted in a significantly increased antioxidant activity, as well as total phenolic and flavonoid content (p < 0.001). The wine samples that underwent maceration scored significantly lower in their appearance, aroma and taste (p < 0.05), which could be caused by a higher phenolic content and specific taste. The dynamics of BA formation in wine, evaluated using multiple factor analysis, highlighted that the maceration and maceration with an added yeast culture significantly affected these processes (p < 0.05). Microbiological examination promoted stable yeast counts during the maceration process, ensuring their longer presence during fermentation. Future research should aim to optimize maceration time in order to enhance the sensory quality of macerated wines without increasing the BA concentration, especially that of histamine.

This study investigates the effect of maceration and different winemaking techniques on the species diversity of yeasts in white wines from the Slovak Tokay wine region, known for its traditional white wine production. Lipovina grape variety samples were divided into three groups: control (C), macerated (M) and macerated with the addition of a yeast culture (MY). During the entire fermentation process, quantitative and qualitative microbiological analyses of the raw material and must samples were carried out, which resulted in the identification of 60 yeast isolates via the API 20 C AUX biochemical test and MALDI-TOF MS. Identification was further verified via Sanger sequencing of PCR amplicons, which confirmed the presence of less common wild yeasts in Tokay wine must samples, including Aureobasidium pullulans, Cryptococcus magnus, Torulaspora delbrueckii and Rhodotorula sp. The highest species diversity was observed in the macerated group. These findings indicate that the quality and distinctiveness of Slovak Tokay wines can be increased by careful management of the maceration process during winemaking procedures.

The aim of this work was to study the effects of modification of the skin maceration process by adding ascorbic acid and a yeast culture of Saccharomyces cerevisiae on the quality and safety of Welschriesling wine. The pH, total acids, SO₂, and alcohol content were significantly affected by the modification of the maceration (p < 0.001), except for the alcohol variable, which was not influenced by the skin maceration modifications of the measured values (p > 0.05). The antioxidant activity, total polyphenols, flavonoids, and ascorbic acid levels changed significantly during the experiment, including the maceration and maturation periods (p < 0.001). The observed histamine concentrations were below the recommended limit of 10 mg·L⁻¹ in each analysed sample. Histamine (HIS) and tyramine (TYR) amounts were significantly affected by the experimental factors (p < 0.001). After nine months of maturation, wine samples with ascorbic acid had 2.23 ± 0.00 and 0.35 ± 0.00 mg·L⁻¹ HIS and TYR content, respectively. On the other side, macerated wines without ascorbic acid had 3.05 ± 0.10 and 0.37 ± 0.05 mg·L⁻¹ HIS and TYR content, respectively. Modified vinification procedure with ascorbic acid negatively affected wine samples in the overall sensory evaluation scores of the wines (p < 0.001).

Background: Freezing and thawing methods are critical to the final quality of food products. Methods: Our work focuses on evaluating the effect of five thawing protocols (in the refrigerator, at room temperature, in the microwave, and in a water bath at water temperatures of 20 and 40 °C) on the physicochemical properties, color, sensory properties, content of bioactive compounds, and antioxidant activity in frozen fruits of Fragaria spp. from different retail chains (n = 7) and from diverse countries of origin. Results: We found that although thawing at room temperature is a slow process, it best preserved the original quality of the strawberries when compared with other methods. Different thawing protocols had various effects on the color, sensory properties, polyphenol profile (TPC, TFC, TPA, and anthocyanins determined spectrophotometrically), and antioxidant activity (DPPH method) of strawberries. Our results indicate that each evaluated thawing method was viable. Conclusions: This study can provide a basis for selecting appropriate thawing processes in the strawberry processing industry based on the intended use of the food for further processing.