Metal and metalloid profile as a fingerprint for traceability of wines under any Galician protected designation of origin

 Journal of Food Composition and Analysis, 102, 104043, 2021

Effective and cheap methods for detecting fraud and, guaranteeing wine authenticity, are of paramount importance in the sector. In this sense, three different kinds of prediction models (random forest, artificial neural networks, and support vector machines) were developed to classify wines, according to their element contents (metals and metalloids, obtained using an inductively coupled plasma with a quadrupole mass spectrometer, and an optic emission spectrophotometer). One models were developed using 45 inputs variables, and then the models were subjected to a process of reducing variables to simplify models and save material and time costs. A total accuracy was reached in all phases for the white wines-random forest models. From a practical point of view, the accuracy and the errors obtained by the selected models (except for red wines-artificial neural network developed using reduced variables) are acceptable. The models developed with fewer variables, can make the prediction task easier.

Management of Wine Aroma Compounds: Principal Basis and Future Perspectives

Book Chapter in: 

Winemaking - Stabilization, Aging Chemistry and Biochemistry

DOI: 10.5772/intechopen.92973

Wine’s aroma is defined by volatile and non-volatile compounds that contribute to its make-up. The complex variety of volatile compounds, coming from grapes, interact with other non-volatile substances of the wine as precursors of wine’s aroma, known as primary aromas, which give the aroma of the young wine. The volatile compounds present in the skin and in the grape juice change according to the grape variety. Most of wine volatile compounds responsible for aroma are linked to sugars and they initially form odorless glycosides. Through the process of hydrolysis, they are reverted into an aromatic form. Chemical reactions among these compounds occur during the fermentation and in the first months of a wine’s existence, triggering fast and multiple modifications in wine’s aroma at this point. As wine ages and matures, changes and development in aroma will continue to take place but at a slower and more gradual pace. The study of the compounds responsible for aroma and flavor, as well as their correlation with the wine quality, is ongoing. Improving the knowledge of wine aromatic compounds could increase the risk of its potential adulteration; however, consumers prefer wine for its natural origin, so this scenario is unlikely in the future.

Dissipation of Three Fungicides and Their Effects on Anthocyanins and Color of Monastrell Red Wines

Int. J. Mol. Sci. 2019, 20(6), 1447

DOI: 10.3390/ijms20061447

The effect of fungicides on fermentation is of paramount importance to control the quality and safety of wines. In this work, the quality (enological parameters, color, phenolic content, antioxidant activity, and fungicide residues) of wines from Monastrell grapes fortified with iprovalicarb, mepanipyrim, and tetraconazole fungicides was evaluated. Along the winemaking process, initial residues of mepanipyrim and tetraconazole were removed in more than 90% while the dissipation of iprovalicarb was around 73%. Significant statistical differences were found in the presence of iprovalicarb and mepanipyrim residues, especially at the highest concentration assayed. For both fungicides, increases in the volatile acidity (between 4 and 8.6 times), the lactic acid content (between 8.6 and 20.5 times), the percentage of polymeric anthocyanins (between 1.3 and 1.7 times), and also a slight increase of the total phenolic index and the total anthocyanin content determined by spectrophotometry were observed. On the contrary, the total monomeric anthocyanins content decreased about 16.3% and 28.6% in the presence of iprovalicarb and mepanipyrim, respectively. These results could be related to a higher development of acetic acid or lactic bacteria in the presence of these fungicides. The color of the final wines was also different in comparison with the control, with a higher yellow component, color intensity, tonality, and hue angle because of pH changes in the medium. Tetraconazole fermentations had a more similar trend to the control wine, probably due to the lower concentration of this fungicide in the grape must at the initial time. No effects on the antioxidant activity was observed for any of the target fungicides. A multivariate statistical analysis was done to view the interrelationships between different variables (color and anthocyanins profile). The obtained model allowed the wines to be separated according to the fungicide treatment applied.

Prediction Models to Control Aging Time in Red Wine

Molecules 2019, 24(5), 826

DOI: 10.3390/molecules24050826

A combination of physical-chemical analysis has been used to monitor the aging of red wines from D.O. Toro (Spain). The changes in the chemical composition of wines that occur over the aging time can be used to distinguish between wine samples collected after one, four, seven and ten months of aging. Different computational models were used to develop a good authenticity tool to certify wines. In this research, different models have been developed: Artificial Neural Network models (ANNs), Support Vector Machine (SVM) and Random Forest (RF) models. The results obtained for the ANN model developed with sigmoidal function in the output neuron and the RF model permit us to determine the aging time, with an average absolute percentage deviation below 1%, so it can be concluded that these two models have demonstrated their capacity to predict the age of wine.

Fungicide residues affect the sensory properties and flavonoid composition of red wine

Journal of Food Composition and Analysis, 66 (2018) 185-192

doi.org/10.1016/j.jfca.2017.12.021

The influence of four fungicide treatments [viz., metrafenone, boscalid + kresoxim-methyl, fenhexamid and mepanipyrim, which are typically used to control downy mildew (Plasmopara viticola) and grey mould (Botrytis cinerea)] on the composition of Tempranillo red wines was assessed by examining changes in phenolic composition, colour and aroma profile in wines from pesticide-treated grapes in relation to control wines made from untreated grapes. The results were also compared with those for wine of a previous vintage in order to ascertain whether fungicide-related changes were comparable to vintage-related changes. Only the boscalid + kresoxim-methyl treatment led to significant differences in wine of the 2013 vintage; thus, it increased the contents in monomeric anthocyanins (58%) and flavan-3-ols (36%), and also colour lightness (20%), but decreased the contribution of the ripe (42%) and fresh fruits (59%) odorant series. These results seemingly confirm that the presence of boscalid + kresoxim-methyl residues in must impairs the sensory quality of the resulting wine by diminishing its brightness and aroma. Differences varied markedly between years, which suggests that the course of the fermentation process is influenced not only by the composition of the grapes but also by the presence of the fungicide.

A critical review on the applications of artificial neural networks in winemaking technology

Critical Reviews in Food Science and Nutrition

http://dx.doi.org/10.1080/10408398.2015.1078277

Since their development in 1943, artificial neural networks were extended into applications in many fields. Last twenty years have brought their introduction into winery, where they were applied following four basic purposes: authenticity assurance systems, electronic sensory devices, production optimization methods, and artificial vision in image treatment tools, with successful and promising results. This work reviews the most significant approaches for neural networks in winemaking technologies with the aim of producing a clear and useful review document.

Dissipation of fungicides residues along winemaking, and their effects on fermentation and the volatile composition of wines

Journal of Agricultural and Food Chemistry

The effects of four fungicides commonly used for the control of fungal diseases in vines and grapes in the course of winemaking was tested. The concentration of fungicide residues was monitored throughout the process in order to establish their kinetics of dissipation. In all cases the percentages of dissipation were higher than 68% which shows the detoxificant effect of the winemaking process. On the other hand, the effect of the fungicide residues on the aroma composition of Tempranillo red wines was tested.

A Critical Review on the Applications of Artificial Neural Networks in Winemaking Technology

Critical Reviews in Food Science and Nutrition

DOI:10.1080/10408398.2015.1078277

Since their development in 1943, artificial neural networks were extended into applications in many fields. Last twenty years have brought their introduction into winery, where they were applied following four basic purposes: authenticity assurance systems, electronic sensory devices, production optimization methods, and artificial vision in image treatment tools, with successful and promising results. This work reviews the most significant approaches for neural networks in winemaking technologies with the aim of producing a clear and useful review document.

Effects of sugar concentration processes in grapes and wine aging on aroma compounds of sweet wines—a review

Critical Reviews in Food Science and Nutrition, 55(8), 2015, 1053-1073

DOI 10.1080/10408398.2012.680524

Dessert sweet wines from Europe and North America are described in this review from two points of view: both their aroma profile and also their sensorial description. There are growing literature data about the chemical composition and sensory properties of these wines. Wines were grouped according to the production method (concentration of sugars in grapes) and to the aging process of wine (oxidative, biological, or a combination of both and aging in the bottle). It was found that wines natively sweets and wines fortified with liquors differ in their volatile compounds. Sensory properties of these wines include those of dried fruit (raisins), red berries, honey, chocolate and vanilla, which is contributing to their growing sales. However, there is still a need for scientific research on the understanding of the mechanisms for wine flavor enhancement.

Evaluation of the effect of fenhexamid and mepanipyrim in the volatile composition of Tempranillo and Graciano wines

Food Research International

Volume 71, May 2015, Pages 108–117

doi:10.1016/j.foodres.2015.02.025

Grapes from Vitis vinifera var. Tempranillo and Graciano of La Rioja (North Central Spain) were vinified after addition of two fungicides (mepanipyrim and fenhexamid) at concentrations corresponding to their MRLs. These fungicides are commonly used in the vine growing to control botrytis disease. The fungicide effect throughout winemaking on the volatile composition and aroma profile of the final wines was evaluated, together with the level of fungicide residues in the final wines that were found to be safe for consumers. Concentrations of C13-norisoprenoids in Graciano wines obtained after the addition of both active substances showed the greatest variations with respect to control wine; whereas the concentration of volatile compounds in Tempranillo wines were seemingly unaffected by the presence of fungicide residues. On the other hand, the aroma profile of monovarietal red wines was evaluated by using odorant series which included volatile compounds with similar odour descriptors. In this sense, supplementation with the antifungals seemed to increase the OAV for the ripe fruit series with respect to the control wines in Graciano wines.

Sweet, reinforced and fortified wines: grape biochemistry, technology and vinification

Journal of Wine Research (2015) 26, 64-66

DOI:10.1080/09571264.2015.1009252

Wine Aroma Compounds in Grapes: A Critical Review

Critical Reviews in Food Science and Nutrition, 2015, 55(2), 202-218

Volatile organic compounds are vital to wine quality, determining their aroma and varietal characteristics. Which are present, and in what quantity, depends on the cultivar, the situation and soil of the vineyard, weather, cultivation methods, and wine-making practices. Here, we review the literature on the development of wine aroma compounds in grapes, and how it is affected by the above-named factors. Increasing understanding of these processes at the molecular level will aid vine growers in the optimal selection of harvest dates and other decisions favoring the consistent production of balanced, flavorful berries.