Raluca-Ștefania Rădoi-Encea

The industrial use of non-Saccharomyces yeasts offers a robust bioprocess strategy for modulating volatile biochemical profiles and reducing climate-driven ethanol production in fermented beverages. This study explores the metabolic diversity of indigenous non-Saccharomyces, with a particular focus on Starmerella bacillaris MI151, selected for sequential inoculation with Saccharomyces cerevisiae MI118. Pilot-scale bioreactor fermentations (25 L) of two Romanian matrix-specific aromatic grape cultivars, Busuioacă de Bohotin and Tămâioasă Românească, exhibited clear strain-dependent carbon flux changes. The sequential culture actively triggered the glycerol-pyruvic pathway, which consistently reduced the final ethanol concentration to up to 0.94% (v/v) and maintained a balanced profile of volatile compounds. GC-MS-based metabolomic profiling revealed substantial changes in the esterification kinetics and glycosidic precursor cleavage. The sequential fermentation resulted in a synergistic increase in n-hexyl acetate (up to 2310.01 µg/L) and bypassing of the standard enzymatic repression, freeing highly volatile monoterpenes (β-citronellol and β-geraniol) in the analyzed matrices. This targeted microbial system successfully modulated the organic acid–phenolic balance, neutralizing harsh structural finishes, as confirmed by quantitative sensory mapping. Finally, these specific local yeast strains exhibit strong bioprocess scalability, offering a predictable, non-engineered strategy to lower the ethanol yield while driving targeted flavor enhancement in climate-vulnerable viticultural regions.

Celery (Apium graveolens), rosehip (Rosa canina), and blackcurrant (Ribes nigrum) powders (1–3%, w/w) were evaluated in sous-vide pheasant meat prepared with or without 1.8% NaCl and stored for 28 days at 4 °C. Measurements included proximate composition, pH and titratable acidity, instrumental texture and color, FRAP, ABTS, Folin–Ciocâlteu-reactive compounds, TBARS, nitrate/nitrite, chemical-spoilage screening, and microbial counts; sensory quality was assessed descriptively by a laboratory panel on day 28. Mean cooking loss was 22.11% in salted and 24.10% in unsalted samples. At day 28, 3% rosehip and blackcurrant formulations had total viable counts of 3.80–4.16 log₁₀ CFU/g, compared with 5.78–6.28 log₁₀ CFU/g in controls. Their FRAP values were 2.83–3.23 µmol TE/g dry matter and TBARS values were 0.43–0.57 mg MDA/kg, compared with 1.00–1.05 µmol TE/g dry matter and 1.45–1.53 mg MDA/kg in controls. Celery at 3% retained approximately 170 mg/kg nitrate and 13.3–13.4 mg/kg nitrite. Rosehip and blackcurrant, particularly at 3%, provided the most favorable combination of measured quality attributes under the tested conditions. These findings demonstrate ingredient-specific effects but do not validate pathogen control, commercial shelf life, or population-level consumer preference.

The present study aims to characterize five fish-based catering dishes, cooked by sous vide, by convection and microwaves in terms of their biochemical content, microbial load, and sensory analysis. The product cooked by using convection had the highest levels of MUFAs, PUFAs, and SFAs and the lowest levels of vitamin PP, riboflavin, and niacin. The sous vide maintained the highest levels of retinol, tocopherol, riboflavin, and niacin. Microwaves triggered the greatest decrease in vitamin content. All microbiological indicators exhibited levels below the acceptable limits, except for the level of fungi in the sous vide cooked product. Shelf life was estimated at 5 days for the product cooked by convection and immediately refrigerated and at 50 days for the product cooked by convection and immediately frozen. The most appreciated product from the sensory standpoint, which falls under fine dining, was the one cooked by convection and served immediately. The sous vide dish, the microwaved dish, and those refrigerated/frozen after cooking were undervalued.

Consumers are increasingly demanding traditional beverages such as wines that are obtained through innovative technologies and that use indigenous yeasts to preserve the concept of `terroir`. The paper presents the study performed for the exploitation the microbial diversity in the Pietroasa wine region in Romania and to obtain autochthones yeasts biomass. Yeasts were isolated from grapes and must from Feteasca regala FR) and Cabernet Sauvignon (CS) varieties cultivated at the Pietroasa Viticulture and Vinification Research and Development Station. Five yeast isolates were selected and identified by the MALDI-TOF, these belonging to the S. cerevisiae and non-Saccharomyces genera. By using these yeast isolates, active dry biomass was obtained through fermentation on a substrate based on sterilised diluted must (from the Feteasca regala and Cabernet Sauvignon varieties), synthetic sterilised media, followed by freeze-drying. Subsequently, the active dry biomass was used to obtain wines, using two types of nutrients: ET (Energyvin Thiols) and NO (Nutristart® ORG). All studied yeast isolates showed a promising potential for obtaining white wine from Feteasca regala grapes and rosé wine from the Cabernet Sauvignon grapes variety.

Winemaking in Romania has a long-lasting history and traditions and its viticulture dates back centuries. The present work is focused on the development of wine yeast isolation and selection performed in different Romanian winemaking regions during past decades, presenting the advanement of the methods and techniques employed, correlated with the impact on wine quality improvement. Apart from the historical side of such work, the findings will reveal how scientific advancement in the country was correlated with worldwide research in the topic and influenced local wines’ typicity. To create an overall picture of the local specificities, the work refers to local grape varieties and the characteristics of the obtained wines by the use of local yeasts as compared to commercial ones. Numerous autochthonous strains of Saccharomyces were isolated from Romanian vineyards, of which several demonstrated strong oenological characteristics. Meanwhile, different non-Saccharomyces yeast strains were also isolated and are nowadays receiving the attention of researchers seeking to develop new wines according to wine market tendencies and to support wine’s national identity.