Search Results (4)

Shoot density is a key viticultural factor modulating canopy microclimate, berry composition, and wine quality, although yield–quality relationships are strongly influenced by environmental conditions. Saignée, a winemaking technique involving partial juice removal prior to fermentation, increases the skin-to-juice ratio and may enhance phenolic extraction. This study assessed the combined effects of shoot density (33 [T1], 20 [T2], and 15 [T3] shoots/m) and saignée (20% vs. control) on yield, grape composition, and wine chemical and sensory properties in Malbec across two vintages (2021–2022). At harvest, the pruning weight, yield components, general maturity parameters, and phenolic composition were measured. The wines were analysed for their phenolic and elemental composition, polysaccharides and volatile compounds, colour, and sensory attributes. T1 exhibited the highest yields and vegetative imbalance, whereas T2 and T3 achieved optimal Ravaz indices. The general grape maturity parameters were unaffected; however, T3 had increased berry phenolic content in 2022. T2 and T3 had enhanced wine tannins, total phenols, and polymeric pigments, particularly in 2022. Saignée increased the pH, potassium, total phenols, tannins, and acylated anthocyanins. Targeting yields near 4 kg/vine (≈10,500 kg/ha) improved vine balance and phenolic composition, although the responses were strongly modulated by interannual variability. Full article

Sea buckthorn (Hippophae rhamnoides) is a valuable plant rich in biologically active compounds, mainly found in its berries and leaves. The harvesting process, which includes pruning, freezing, and shaking, leaves behind large amounts of biomass and juice-pressing residues, typically composted. The aim of this study is to expand knowledge of the valorization of sea buckthorn secondary raw materials by applying an innovative pressure cyclic solid–liquid (PCSL) extraction method and to develop value-added functional food products. Extraction was performed in 20 and 60 cycles, each lasting from 2 to 10 min. The highest concentrations of proanthocyanidins (5.51 g_CE/L) and total phenolics (12.42 g_GAE/L) were obtained under prolonged conditions, but the L-4 extract (20 cycles × 2 min) was selected for kombucha production due to its favorable balance between efficiency and sustainability. Microbial safety evaluation showed that kombucha with sea buckthorn leaf extract exhibited significantly stronger antimicrobial activity against tested pathogens compared to green tea kombucha. Additionally, sensory analysis revealed higher consumer acceptability of beverages enriched with sea buckthorn extracts. Shotgun metagenomic analysis identified high microbial diversity in the M. gisevii MI-2 starter culture and fermented kombucha products (227 bacteria and 44 eukaryotes), most of which (92.5% bacteria, 77.8% eukaryotes) remain viable and contribute to fermentation dynamics. New biotechnological strategies and genetic modifications raise concerns about the safe use of microorganisms in food production. To address these issues, these findings provide a foundation for future strategies aimed at the safe application of beneficial microorganisms in food biotechnology and support the long-term goals of the European Green Deal by promoting sustainable biomass valorization and circular economy advancement in the food sector. Full article

The fermentation of prune juice significantly enhances its nutritional profile, antioxidant capacity, and flavor characteristics. In this study, Non-Saccharomyces cerevisiae and Lactiplantibacillus plantarum were used to co-ferment prune juice to systematically investigate the dynamic changes in physicochemical properties and antioxidant activity during fermentation. The evolution of volatile compounds across fermentation stages was analyzed using gas chromatography–ion mobility spectroscopy (GC-IMS) combined with chemometric methods, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The results showed that after fermentation, the total acidity (TA), total phenolic content (TPC), and total flavonoid content (TFC) increased by 37.35%, 20.28%, and 28.95%, respectively. Meanwhile, the pH, total soluble solids (TSS), and reducing sugars (RS) decreased by 16.87%, 23.36%, and 39.94%, respectively. Additionally, the DPPH radical scavenging capacity and ABTS radical scavenging capacity improved by 76.16% and 57.25% during fermentation process. A total of 37 volatile compounds were identified across the four fermentation stages of prune juice (PJ). These compounds included 14 esters, 8 alcohols, 7 aldehydes, 4 terpenoids, 3 ketones, and 1 amine. Considerable quantities of organic acids and free amino acids were detected in samples from all fermentation phases. Among these, lactic acid, citric acid, and D-glucuronic acid exhibited significant increases in their concentration (p < 0.05). In the free amino acid profile of fermented prune juice (FPJ), asparagine was the most abundant component, followed by glutamine and proline. Full article

The production of beneficial microorganisms is the first step to obtain a commercial-based product for application in agriculture. In this study, prickly pear (Opuntia ficus-indica) pruning waste was evaluated as a raw material for the production of large amounts of Plant Growth Promoting Microorganisms (PGPMs) reducing the number of generated wastes. Specifically, five PGPMs constituting a synthetic microbial consortium with complementing plant growth-promoting traits were grown on a laboratory scale and, subsequently, on a pilot scale using a 21-L bioreactor. Primarily, the physical-chemical characterization of the culture medium obtained from the juice of Opuntia cladodes was carried out, revealing the presence of sugars and organic acids with different molar ratios. Compared to conventional media, the waste medium did not show significant differences in bacterial growth efficiency. Instead, the survival rates of the bacteria grown in cladodes juice media, after air-drying on zeolite or freeze-drying, were significantly higher than those observed when they were grown in conventional media. The present work is the first conducted on a pilot-scale that maximizes the production of PGPMs in submerged fermentation using cladodes juice from Opuntia, reducing both economic and environmental impacts associated with the generation of wastes. Full article