In classical methods of wine production, amino acids play a critical role, as they are fundamental to all types of fermentation. Beyond their consumption in fermentative processes, amino acids undergo several transformations, such as decarboxylation, which produces biogenic amines. These biogenic amines can increase under certain conditions, such as the presence of spoilage bacteria or during malolactic fermentation. Alternative methods of vinification were applied, using sulfur dioxide as a preservative (+SO₂) and methods without added sulfites. Alternative methods of vinification were applied using sulfur dioxide as a preservative (+SO₂) and methods without added sulfite (−SO₂). Monitoring was conducted for Cabernet Sauvignon red (CS), Cabernet Sauvignon rosé (CSR), Fetească regală still (FR), and Fetească regală frizzante (FRF). Alternative procedures employed the use of Pichia kluyveri for its ability to block the oxidation reactions of grapes, malolactic fermentation for all wines without sulfur dioxide (−SO₂) to ensure superior stability, and the use of several tannin mixtures to avoid oxidation reactions. Correlations were considered between the amino acids and biogenic amines that have a direct relation through decarboxylation or deamination. The pH of the wines, total acidity, and volatile acidity as principal factors of microbiological wine evolution remained constant. The highest mean concentrations of the detected biogenic amines were putrescine at 23.71 ± 4.82 mg/L (CSRSO₂), tyramine at 14.62 ± 1.50 mg/L (FR-SO₂), cadaverine at 4.36 ± 1.19 mg/L (CS-SO₂), histamine at 2.66 ± 2.19 mg/L (FR + SO₂), and spermidine at 9.78 ± 7.19 mg/L (FR + SO₂). The wine conditions ensured the inhibition of decarboxylases, but some correlations were found with the corresponding amino acids such as glutamine (r = −0.885, p < 0.05) (CSR-SO₂), tyrosine (r = −0,858, p < 0.05) (FR-SO₂), lysine (r = −0.906, p < 0.05) (FR-SO₂), and histamine (r = −0.987, p < 0.05) (CSR-SO₂). Multivariate analysis was performed, and no statistical differences were found between samples with (+SO₂) and without added sulfur dioxide (−SO₂). The vinification conditions ensured the wines’ stability and preservation and the conditions of producing biogenic amines at the lowest levels in order to not interfere with the olfactive and gustative characteristics.

This study evaluates the influence of terroir on the physico-chemical characteristics and aromatic profiles of Fetească albă wines from five major Romanian wine regions. By analysing key factors such as soil types, climatic conditions, and winemaking techniques, the study aims to understand their impact on wine composition and quality. The study includes the analysis of superior alcohols, fatty acids, esters, carbonyl compounds, terpenes, and 4-mercapto-4-methylpentan-2-one, which are essential in defining the aromatic complexity of the wines. The results show how fermentation conditions, temperature control, microbial activity, and oxidative exposure contribute to the evolution of these compounds, influencing the sensory profiles. Significant differences in compound concentrations were observed across the regions, with wines from Dealu Mare and Murfatlar exhibiting high ester content and aromatic complexity, while those from Dealul Bujorului and Panciu showed elevated volatile acids and aromatic alcohols, suggesting distinct fermentation dynamics. Climatic factors, such as temperature and precipitation, played a crucial role in shaping the volatile composition, with elevated temperatures in 2021 enhancing ester formation and higher alcohol production. This study demonstrates the critical role of terroir and winemaking practices in shaping the aromatic and sensory characteristics of Romanian Fetească albă wines.

The biochemistry and physiology of raw material, the metabolism of microorganisms, and the methods used for processing and storage can affect the stability of wines. Due to the antimicrobial action of sulfur dioxide and dimethyl dicarbonate, the aim of this study is to determine the optimal treatment protocol to maintain the physico–chemical and microbiological stability of white wines with high residual sugar. Thus, the present research focuses on analyzing the influence of both treatments, combined or separate, on 45 wine samples obtained from a blend of Muscat Ottonel and Fetească Regală grape varieties, where different doses of 6% aqueous SO₂ solution (40, 80, and 160 mg/L) and dimethyl bicarbonate (0, 100, and 200 mg/L) were used. In order to assess the ability of dimethyl dicarbonate to suppress microorganisms, varying concentrations of Brettanomyces bruxellensis and Schizosaccharomyces pombe yeasts were inoculated (0, 30, 100 CFU/mL wine). The results indicate that, while sulfur dioxide cannot be entirely substituted in wines, both treatments can effectively lower or inhibit the activity of spoilage microorganisms. For the wines’ physico–chemical and microbiological stability, the treatment that used the synergistic force of sulfur dioxide (160 mg/L) and dimethyl dicarbonate (200 mg/L wine) performed the best.

In the wine-making process, the yeasts form over 20 higher alcohols that improve the sensation of palatine veil for the wine. The amount of higher alcohols is lower for white and rosé wines obtained from clarified musts fermented at moderate temperatures. The formation of higher alcohols is confirmed by the fact that the addition of certain nitrogen compounds to a glucose-containing culture medium leads, after the fermentation, to an increase in the higher alcohol content. Data evaluate by comparison the levels of higher alcohols, esters and aldehydes, important to fermentation process in case of several wines from Panciu region. The wine-making was done by classical methods and by using specific protocols for low content sulphur dioxide. This study is focused to compare wines obtained from two grape varieties produced at industrial level: Feteasca regala vs. Feteasca regala Frizzante and Cabernet Sauvignon rosé vs. Cabernet Sauvignon. The compounds were analyzed by GC-FID method with head-space technique for methanol, 1-propanol, 2-methyl-propanol, 1-butanol, ethyl acetate, ethyl lactate, isoamyl acetate and acetaldehyde. The results showed that in almost every comparative study the levels of aroma compounds are maintained, when compared with the wines with low content of sulphur dioxide. Tuckey test showed that 1-propanol and ethyl acetate register statistically significant differences for Cabernet Sauvignon rosé and for Feteasca regala Frizzante.

The biochemistry and physiology of the raw material, the metabolism of microorganisms, the methods used for processing and storage can affect the stability of wines. Due to the antimicrobial action of sulfur dioxide and dimethyl dicarbonate, the aim of the study is to determine the optimal treatment protocol to maintain physico-chemical and microbiological stability of white wines with high residual sugar. Thus, the present research focuses on analyzing the influence of both treatments, combined or separate, on 45 wine samples obtained from a blend of Muscat Ottonel and Fetească regală grape varieties, where different doses of 6% aqueous SO2 solution (40, 80, and 160 mg/L) and dimethyl bicarbonate (0, 100, and 200 mg/L) were used. In order to assess the ability of dimethyl dicarbonate to suppress microorganisms, varying concentrations of Brettanomyces bruxellensis and Schizosaccharomyces pombe yeasts were inoculated (0, 30, 100 cfu/mL wine). The results indicate that, while sulfur dioxide cannot be entirely substituted in wines, both treatments can effectively lower or inhibit the activity of spoilage microorganisms. For the wines' physicochemical and microbiological stability, the treatment that used the synergistic force of sulfur dioxide (160 mg/L) and dimethyl dicarbonate (200 mg/L wine) performed the best.

The increasing global demand for sparkling wines has encouraged the exploration of alternative grape varieties and emerging production regions. This study evaluated the potential of three indigenous Romanian grape varieties (Fetească regală, Tămâioasă românească, and Fetească albă) for sparkling wine production using the méthode champenoise, with grapes sourced from the ullu Mare region. The wines were characterized at two aging intervals (9 and 36 months on lees), with analyses performed on both disgorged and undisgorged samples to assess changes in physicochemical parameters, color attributes, volatile composition, and sensory properties. All varieties exhibited relatively high acidity (6.12–6.53 g/L), particularly Fetească regală (6.37–6.53 g/L), supporting their suitability for sparkling wine production. Extended lees aging enhanced the development of complex tertiary and quaternary aromas while preserving intrinsic floral and fruity attributes. Volatile analysis revealed aging-related increases in higher alcohols and medium-chain fatty acids, with 1-pentanol reaching 106.8 mg L⁻¹ and octanoic acid increasing from approximately 4.2 to 7.9 mg L⁻¹ after 36 months. Principal component analysis explained over 70% of the total variance, discriminating wines according to grape variety and maturation time. This study aimed to provide a detailed characterization of these sparkling wines, integrating physicochemical, chromatic, volatile, and sensorial analyses to evaluate their quality and enological potential.