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Red wine grapes are qualitatively evaluated for their content in polyphenols and anthocyanins. Due to certain conditions (weather, latitude, temperature), the concentration of these compounds may be not at the right level for reaching a high-quality wine, thus postharvest technologies can be operated as a remediation strategy. Ethanol is a secondary volatile metabolite and its application has been demonstrated to delay fruit ripening, to reduce decay, and to increase secondary metabolites. The present study investigates the effects of ethanol post-harvest application on wine grapes’ metabolism and composition. Red wine grapes (Vitis Vinifera L. cv Aglianico) were exposed to different ethanol doses (0.25, 0.5, or 1 mL L−1) for 12, 24, or 36 h. Ethanol increased sugar concentration, malic acid, free amino nitrogen, polyphenols, and anthocyanins. Particularly, anthocyanins reached an average value of 1820 mg/L in treated samples versus the 1200 mg/L of control grapes already after 12 h whatever the concentration was. Moreover, the highest concentration of ethanol modified berry metabolism shifting from aerobic to anaerobic one. Obtained results suggest that 12 h of ethanol postharvest treatment could be an interesting solution to improve anthocyanins in wine grapes, especially when the quality is not as good as expected.

BACKGROUND: 'Xynisteri' is considered as the reference white grape cultivar in Cyprus with remarkable adaptation to adverse edaphoclimatic conditions and appreciable oenological properties that renders it as an appropriate cultivar for studies within a global context due to climate change. To this aim, two distinct non‐irrigated plots with different climatic conditions, soil properties and levels of rainfall were selected; Koilani [KO, altitude 800 m, 76% calcium carbonate (CaCO3) content, pH 7.97, average temperature: 16.5 °C, rainfall: 229 mm] and Kyperounda (KY, altitude 1200 m, CaCO3‐free soil, pH 6.47, average temperature: 14.9 °C, rainfall: 658 mm). An array of physiological, biochemical and qualitative indices during successive developmental stages (BBCH 75–89) were determined. During the advanced on‐vine developmental stages (BBCH 85–89), the aromatic profile of grapes was assessed with the employment of gas chromatography–mass spectrometry (GC–MS). Such analysis was complemented with non‐destructive chemometric analyses. RESULTS: Berry ripening process substantially differed on the examined plots; BBCH 89 stage reached at 267 and 303 Julian days for KO and KY, respectively. Results indicated that berry weight, soluble solids content (SSC) and α‐amino nitrogen were higher in KO than in KY, with exception made for ammonium nitrogen content. A total of 75 compounds, including aliphatic alcohols, benzenic compounds, phenols, vanillins, monoterpenes and C13‐norisoprenoids were identified and quantified. The variations of mesoclimatic conditions affected the volatile organic compound (VOC) profiles at the fully‐ripe stage, showing a considerable rise in glycosylated aroma compounds, especially monoterpenes and benzenic compounds. In particular, the higher amount of glycosylated aroma compounds were obtained in KY berries up to mid‐ripe, whereas KO showed higher glycosylated aroma compounds at fully‐ripe stage. Results reported herein indicate that aroma profile of 'Xynisteri' grapes varied substantially in the examined terroirs. Interestingly, the limited rainfall in KΟ non‐irrigated vine did not compromise qualitative and aromatic properties of berries. CONCLUSIONS: The present study aimed at dissecting the impact of terroir on bush‐trained, non‐irrigated grapevines of a cultivar appropriate for extreme climate change scenarios. The volatilome fingerprint was highly variable among the examined plots; such results can be further exploited at vinification level towards production of single vineyard premium end products. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Botrytis cinerea (Bc) is the causative agent of gray mold disease in wine grape bunches. Under particular climatic and edaphic conditions, typical of some wine regions, the grapes infected by this fungus can develop noble rot, the basic phenomenon for the production of sweet botrytized wines or some high‐quality dry wines, such as Amarone. The possibility of early detection of noble rot on plants and at postharvest is an interesting option for managing botrytized wines. RESULTS: The present work aimed at early detection of noble rot and monitoring its development, at postharvest, on Trebbiano wine grapes by means of destructive and non‐destructive analytical approaches (e.g., electronic nose and near‐infrared spectroscopy). The development of Bc led to substantial modifications in grape composition, including dehydration, biosynthesis, and accumulation of different compounds due to Bc metabolism, grape stress responses, or both. However, these modifications are appreciable, notably at advanced stages of infection. Consequently, a specific focus was to monitor the infection in the first 72 h post inoculation for testing, potentially through non‐destructive technologies, and to identify the real early stages of Bc development. CONCLUSION: The destructive chemical analyses performed over the 16 monitored days confirmed what is widely reported in the literature regarding the metabolic/compositional changes that occur following the development of Bc. Moreover, non‐destructive technologies allowed us to identify the evolution of Bc, even at early stages of its presence. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Ozone (O3) is currently employed in wineries as a sanitizing agent and is used to control microbial growth and infection. This molecule decomposes spontaneously to oxygen upon application and the use of ozonated water can represent an alternative for the control of pathogens in the vineyard. Entire canopies of Vitis vinifera (cv Vermentino) plants have been sprayed throughout the vegetative growth with water saturated with O3 to assess the effects of these treatments in reducing the microorganism population, and to evaluate if and how the oxidative stress, induced in the plant by this strong oxidizing agent, affects fruit development, the activity of the cellular antioxidant system, and the production of aromas by the grape berries at ripening. Ozonated water treatments resulted in a partial control of microorganism population, especially considering fungi. Furthermore, the treatments induced a slight delay in the technological maturity of grapes, a significant increase in antioxidant capacity and changes of aroma profile of the grapes at harvest, with an accumulation of monoterpenes. In general, ozonized water treatments showed promising results and seem to be a feasible protocol to be applied in the vineyard in order to reduce the use of chemicals.

Background: 'Xynisteri' is the reference Cypriot white cultivar that, despite its significant societal and economic impact, is poorly characterized regarding its qualitative properties, while scarce information exists regarding its aroma profile. In the current study, the effect of leaf removal during fruit set (BBCH 71) on 6‐year cordon‐trained, spur‐pruned grapevines was assessed and an array of physiological, biochemical, and qualitative indices were monitored during successive developmental stages (BBCH 75, BBCH 85, BBCH 87, and BBCH 89). Grapes were additionally monitored for the volatile organic compounds (VOCs) profile during the advanced on‐vine developmental stages (BBCH 85–BBCH 89) with the employment of gas chromatography–mass spectrometry (GC–MS), Fourier‐transform near infrared (FT‐NIR) spectra and electronic nose (E‐nose) techniques. Results: Grape berries from the vines subjected to leaf removal were characterized by higher solid soluble sugars (SSC), titratable acidity (TA), tartaric acid, and ammonium nitrogen contents, while this was not the case for assimilable amino nitrogen (primary amino nitrogen). A total of 75 compounds were identified and quantified, including aliphatic alcohols, benzenic compounds, phenols, vanillins, monoterpenes, and C13‐norisoprenoids. Leaf removal led to enhanced amounts of glycosylated aroma compounds, mainly monoterpenes, and C13‐norisoprenoids. Chemometric analysis, used through FT‐NIR and E‐nose, showed that the aromatic patterns detected were well associated to the grape ripening trend and differences between leaf removal‐treated and control grapes were detectable during fully ripe stage. Conclusion: Leaf removal at fruit set resulted in an overall induction of secondary metabolism, with special reference to glycosylated aroma compounds, namely monoterpenes and C13‐norisoprenoids. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Considering the problems of soil salinization and freshwater scarcity, halophyte plants are indicated as an interesting alternative to conventional crops because these plants thrive in severe environmental conditions (i.e., high salinity, UV radiation). This review identifies halophyte food and non-food uses, discusses the values and areas for innovation and identifies gaps for further research. In relation to human consumption, several research works provide assessments of halophyte nutritional value and nutraceutical properties (i.e., minerals, fibres, proteins, bioactive compounds and low fat). Despite the promising future for halophyte multiple uses, problems related to cultivation, processing and marketing have still to be tackled. Consumption is mainly linked to local gastronomy, tradition, or gourmet cuisine. Market analysis, taste and sensory assessment of halophyte preparations are in their infancy and represent a promising avenue for further research. Knowledge recovery of halophyte food uses is a key to give impetus to supply chain development. [ABSTRACT FROM AUTHOR]