Grape musts differentiation based on selected aroma compounds using SBSE-GC-MS and statistical analysis

Fifty-one aroma compounds in musts from 'Muscat Ottonel', 'Aligoté', 'Muscat of Alexandria' and 'Pedro Ximénez' white grapes have been determined, three of them identified for the first time in grapes. Two fingerprints for each cultivar, based in 6 groups of aroma compounds before and after acidic hydrolysis of the musts were obtained by Multiple Variable Analysis. Only 17 aroma compounds before and 21 after hydrolysis, were selected by their high discriminating power. The Principal Component Analysis carried out with data of these selected compounds provided two components explaining 85.11 % of the overall variance for free aroma compounds and 87.58 % for those obtained after hydrolysis of musts, allowing an objective differentiation of each cultivar

Aspects concerning the predicting possibility of rose wines chromatic parameters on the absorption spectra of musts

Wine color standardization is a difficult but important problem can be solved by proper quantification of important issues, from the conditions of cultivation of vines and ending with way of selling the wine. In this study we have applied multiple regression analysis to achieve mathematical models to assess the CIE Lab parameters - 76 of wines based on chromatic parameters, total phenolic content and anthocyanins of musts, which are well known and easy to calculate. All these variables were measured at 13 rosé wines obtained by prefermentative maceration technology of two red grape varieties Băbească neagră şi Fetească neagră. We obtained two mathematical models for predicting the CIE Lab - 76 parameters that have small standard errors, first using only the L, a, b, C, H° parameters as independent variables, and the second using the total phenolic and anthocyanin content values determined by spectrophotometry. These models can be useful in wineries, especially in moments during winemaking, specifically to achieve rosé and red wines to determine the optimal timing of closing of the grape prefermentative maceration or maceration-fermentation process, resulting less technology interventions and ensure wines colour constancy from year to year

The antioxidant activity evolution in different technological stages of some red wines

The studies regarding the antioxidant activity evolution in different technological stages of some red wines was made at the oenology laboratory of U.S.A.M.V. Iasi and closely with the Center for oenology, Iasi branch of the Romanian Academy. 4 local grape varieties for red wines, Feteasca neagra, Negru de Causani, Babeasca neagra and Busuioaca de Bohotin were chosen as study material, the last one more specifically for rose wines than for the red ones, and the Merlot variety in order to compare the antioxidant capacity of the Romanian varieties to the international ones. These wines were produced with the classical technology for red wines using the classical skin contact maceration process. Six important technological moments was supervised. The phenol compounds content of the samples was analyzed using the total polyphenolic index and the antioxidant activity using the photochemiluminescence method, calculated as ascorbic acid equivalents, mmol/L. Firstly the values of the phenolic compounds and of the antioxidant activity of all the five wines have ascending curves, with lower or higher variations of their amplitude according to the specificity of each wine. The technological stage that determined the maximal values of both the TPI and the antioxidant activity was the second one, the one after the maceration process, which is responsible of the extraction of phenolic compounds from grapes. Towards the end of vinification, these values slowly decreased under the influence of the other vinification processes but depending also on the grape variety. Linear correlations between the TPI and AO.A were determined, these correlations varying also depending on the grape variety and can be consider a specific characteristic of the grape sort

Management of Pesticides from Vineyard to Wines: Focus on Wine Safety and Pesticides Removal by Emerging Technologies

Grapevine (Vitis vinifera L.) represent an important crop, being cultivated in 2018 on 7.4 million hectares worldwide, and with a total production of 77.8 million tonnes. Grapes are susceptible to a large number of fungal pests and insects that may cause important economic losses, reduction of quality and undesired sensory characteristics in wines. A common practice in viticulture is the utilization of chemical reagents, as pesticides, that can insure constant production of high-quality grapes. The use of pesticides in vineyards is an old agricultural practice and although generally beneficial, some concerns are raising due to potential toxic compounds assimilation during wine consumption and human health risks. This chapter offers a complete overview of the most common pesticides used in vineyard and tracks them across grapes, winemaking stages and wines. The impacts of pesticide residues on phenolic compounds and volatile compounds are discussed in details, alongside with emerging technologies for removal of pesticide residues from grapes and wines

Effect of acidity correction on the solubility of tartaric compounds from wines

The paper presents data concerning the effect of acidity correction on the solubility of potassium bitartrate and calcium neutral tartrate, as a result of acid addition (tartaric, malic, citric and succinic) in wines lacking acidity, for improving their organoleptic qualities. The solubility of these compounds was assessed by means of concentration (PC , PCT) and solubility (KST , KS ) products at −4 ºC, by the excess of KHT and CaT at −4 ºC and saturation theoretical temperatures of KHT and CaT. As a result of acidity correction, we have noticed its increase (at the same proportion for all the acids) and a diminution in pH according to added acid: tartaric, lactic, malic, citric and succinic. By adding tartaric acid, wine instability was created, because of potassium bitartrate, by increasing the values of concentration and solubility products, of KHT excess and theoretical saturation temperatures. In case of calcium tartrate, the same acid favoured wine stability, by diminishing the values of the constants. Adding the other acids in wine was good for the solubility of tartaric compounds, because, in all the cases, the values of constants characterizing solubility were diminished

Respiratory and vascular effects of some fractions isolated from red wine

We have isolated a series of fractions (T1–T6) from a sample of red wine and studied their influence on cellular respiration and behaviour of blood vessels, by in vitro analysis of striated muscle and liver of frog (Rana ridibunda, Pall), and of fragments of Wistar rat aorta artery. Different biological effects were registered, according to the type of tissues, composition of fractions (polyphenol proportion), and duration of registrations. The dominant effect on cellular respiration consisted in its stimulation, registered at fractions richer in polyphenols – T2 and T3, more pronounced than that produced by wine and more prominent at liver than at muscles. The same fractions clearly influenced the smooth muscles of aorta artery, determining an important vasodilatation effect. The other fractions had a weaker or inhibiting action on cellular respiration and did not show evident vascular effects. The results pointed out a series of useful pharmacological properties of certain studied wine fractions

Aspects concerning the variation of phenolic compounds and color parameters, according to maceration method, in wines obtained from Fetească Neagră grape variety

This study analyses the way in which different maceration-fermentation methods (ultrasounds maceration, microwave maceration, thermomaceration, classical maceration) influence the extraction of phenolic compounds and the color of Fetească neagră wines. In order to underline the variation of phenolic compounds and color parameters the following determinantions were carried out: D280 index, Folin Ciocalteu index, anthocyans according to pH variation , anthocyans profile, phenolic acids and Cielab76 color determination. The obtained data showed that there are differences between the results’ values in the wines obtained through the four maceration-fermentation procedures. Microwave maceration and thermomaceration have been proved to be the most extractive for phenolic and color compounds

Compositional aspects of quality wines produced in Avereşti vine growing centre of Huşi vineyard, harvest of 2011

The purpose of this paper is to present data on the composition characteristics of quality white wines can be obtained from vine varieties commonly planted in Avereşti vine growing centre of Huşi vineyard in the new climate conditions in recent years due to global warming, that increase the amount of useful temperatures during the growing season and in the maturation of the grapes. In order to obtain wines were used Zghihară, Feteascǎ regală, Aligoté and Fetească albă grape varieties. Experiments were performed on 10 white wines produced in industrial conditions in the plant of S.C. Vinicola Avereşti 2000 S.A. Huşi. During the ripening of the grapes of 2011 weather conditions were favourable for sugars accumulations, which are sufficient to obtain quality dry, semidry and sweet white wines with designation of origin. The paper presents data of the pH value of wines based on the total acidity dependent to the tartaric, malic, citric acid, volatile acids and content of potassium, calcium, magnesium and sodium cations. In all analyzed wines is observed, in general, a low pH, these showing values between 3.070 and 3.222 in dry wines, and between 3.122 and 3.261 for those with residual sugar. Low values in the tartaric acid content (between 1.52 and 1.77 g/L), potassium cations (between 368 and 426 mg/L) and calcium (between 48 and 58 mg/L) at all analyzed wines, can be explained too by tartaric deposits resulting from their retention period during the 2011-2012 winter when temperatures were very low compared to the same periods in previous years. Nonreducing extract values (between 18.26 and 21.07 g/L), in correlation with alcohol concentration values (between 11.01 and 12.05 % vol.), allowed the classification of all reviewed wines in the high quality white wines category with controlled denomination of origin (DOC)

Studiul principalelor caractere fizico-chimice la unele soiuri de viță de vie cultivate în podgoria Iași

The article analyses local, newly created grape varieties for table grapes, in order to highlight valuable sources of germplasm as to fulfill the biological and economic potential of Iasi vineyard, area with a low favourability for table grapes cultivation. The main goal is the analysis of structural, physicochemical and biochemical characterization of local varieties for table grapes. Having information regarding the type and concentrations of biochemical compounds available in the grapes, and the relationships between them, technological characteristics, therapeutic value, as well as sources of germoplasm for other grape varieties. The objectives were to determine the structural characteristics of the grapes at full maturity, determination of physico-chemical characteristics of the studied varieties, as well as their qualitative characteristics

Pesticide residues identified in grape varieties

As the human population continues to grow there is an ever-increasing demand for food production, which means that more and more pesticides will be required to meet these needs. This trend is the same in the winemaking industry with pesticides being used in higher quantities year after year. As pesticides can produce harmful effects on human beings and the environment it is crucial to accurately understand how pesticides travel through the winemaking process. This research sought to monitor the pesticides from two grape varieties. The following six pesticides were analysed: oxathiapiprolin, myclobutanil, iprovalicarb, tebuconazole, chlorantraniliprole, and acetamiprid. Samples were extracted using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method and analysed for the residues of pesticides by liquid chromatography-tandem mass spectrometry. Results indicated that pesticides content in the grape samples ranged between 0.89 ng/g and 18.92 ng/g for Feteasca neagra grape variety. Similar for Cabernet Sauvignon grape values ranged between 0.66 ng/g and 8.24 ng/g. Overall, the recorded levels of pesticides were significantly below the EU maximum residue levels (MRL’s)