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The polyvinylpolypyrrolidone (PVPP) is a high molecular weight vinylpyrrolidone polymer (about 1.000.000) and is water insoluble. Ot is a synthetic fining agent that tends to form bonds with phenolic compounds of lower molecular weight (Sims et al., 1995; Donovan et al., 1998), promoting the reduction in the levels of total polyphenols, phenolic acids, procyanidins, catechins, polyphenols, and protein complexes. Mechanism of adsorption of polyphenols on PVPP is similar to the mechanism of flocculation of gelatin and tannin, with formation of hydrogen bonds between the phenolic groups and oxygen of the amine group of the pyrrolidone ring (Togores, 2018). Currently, the pea protein isolate, an adequate alternative to proteins of animal origin or proteins with an allergenic potential

Abstract. The Serra Gaucha has a high rainfall occurrence during the ripening and harvest. It results in higher use of fungicides, being the copper-based ones, the most commonly used. High levels of this metal can cause stress to the yeast, thus, influencing on the fermentation kinetics. The aim of this study was to evaluate the fermentative behavior of oenological yeast in the presence of copper content in the must. The experiment used the following fungicides: Copper Sulfate, Copper Oxychloride and Copper Hydroxide. Samples were inoculated with S. cerevisiae, S. cerevisiae var. bayanus and Torulaspora delbrueckii and the fermentation was plotted for carbon dioxide production by time. The fermentative kinetics were assessed by the following kinetic parameters: the lag phase time, maximum rate of CO2 production and maximum production of CO2. The study showed that T. delbrueckii had higher sensitivity to copper regarding the lag phase. Copper oxychloride promoted greater latency period in yeast T. delbrueckii and S. cerevisiae. All copper fungicides decreased maximum rate of fermentation, and T. delbrueckii was the most affected. The maximum CO2 production during the fermentations significantly differed only in the presence of copper sulphate.

Ion exchange resins are polymers with high physical and chemical stability, which, upon activation, acquire positive charge (H+) ions which interchange with existing cations during musts or wines treatment. The chemical composition of the grape must, and wines are highly affected by said modifications. This study aimed to evaluate the impact of the cationic resin treatments on the physicochemical and organoleptic characteristics of base white wines for sparkling wine production. Thus for, Chardonnay must was exposed to a cation exchange resin specific for oenological usage, and fermented to obtain wines. Resulting wines included an untreated control sample with pH 3.15 and treated samples with pH 3.08, 3.02 and 2.97. Physicochemical and volatile compounds analyses as well as quantitative sensory evaluations were conducted. The results showed that, on the scenarios tested, treatments with cationic resins before fermentation resulted in wine with higher oxidative stability, with significative variation on the concentration of several volatile compounds that influenced organoleptic perceptions.

Aim: The purpose of this study was to evaluate the in vitro and in vivo efficiency of derivatives of 8-Hydroxyquinoline (8HQ) in controlling the fungus Ilyonectria liriodendri. Methods and Results: The in vitro tests consisted of assessing its susceptibility to the minimal inhibitory concentration (MIC) and the inhibition of mycelial growth. While the in vivo tests consisted of applying and assessing the most effective products for the protection of wounds, in both preventive + curative and curative forms. The MIC values for PH 151 (6Á25 µg ml À1 ) showed better results when compared to the fungicides tebuconazole (>50 µg ml À1 ) and mancozeb (12Á5 µg ml À1 for strain 176 and 25 µg ml À1 for strain 1117). PH 151 significantly inhibited mycelial growth, while mancozeb did not differ from the control. In in vivo tests, PH 151 again demonstrated excellent results in vitro, especially when applied preventively. Conclusions: The derivative of 8HQ PH 151 was effective in controlling the fungus I. liriodendri in vitro and proved to be a promising option for protecting wounds. Significance and Impact of the Study: This study points to the prospect of an effective and safe preventive antifungal product, which would enable the use of pesticides in vine culture to be reduced.

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Soy protein isolate was evaluated as a potential fining agent as an alternative to the predominant protein commercial fining agents (ovalbumin, porcine gelatin, and pea protein isolate). Two red wines (cv. ‘Merlot’ and cv. ‘Lambrusco Maestri’) were finned, bottled, and analyzed for phenolic content, color, turbidity, and sensory profile. Independent of the protein used, fining promoted a reduction in a majority of the phenolic compound, a slight (but significant) reduction of chromatic properties, and a decrease in the turbidity of the wines. A decrease in astringency, persistence, bitterness, and wine body, as well as an increase in brightness, clarity, and acidity, was also observed in all treatments. The application of soy protein isolates yielded similar results to those obtained with other commercial fining agents, both in the physicochemical and the sensory measures, which favors its usage as an alternative to the traditional fining agents of animal-protein origin.

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