A three-phase mathematical model to monitor alcoholic fermentation and phenolic extraction of Vitis Vinifera L. red wines Kiera Lambrecht, Tobias Louw, Wessel du Toit, Jose Luis Aleixandre-Tudo Journal of Food Engineering, 2026 The main goal of this study was to explore the development and validation of a dynamic mathematical model to describe the oenological and phenolic development during the alcoholic fermentation process of red wines. A three-phase model including the cap, must and lees phases was attempted. The model uses grape compositional data to forecast the expected progression of phenolic extraction and production of fermentative products. The likelihood of the calculated parameters was tested on a new set of fermentations to assess model accuracy and robustness. In addition, the model parameters were explored to determine the range of applicability of the proposed mathematical model. For the must phase, the phenolic and some of the most relevant oenological parameters have shown R 2 often higher than 0.8 and mean average predictive error (MAPE) below 20 % indicating comparable levels of accuracy to those presented in literature while also expanding on the number of components of interest. Moreover, model validation has shown that model performance can be affected by fermentation temperature, especially when fermentations are conducted at higher temperatures (28 °C). The mathematical model presented in this study was able to accurately forecast the fermentation kinetics of both phenolic and oenological parameters. The model incorporated the polymerisation of anthocyanins and the transfer of compounds to the lees phase representing a step forward in understanding the kinetics of red wine fermentation and contributes to the development of future methods for monitoring and controlling red wine fermentations. • A three-phase mathematical model to describe red wine fermentations is proposed. • Grape compositional data is used to forecast phenolics and alcoholic fermentation. • Phenolics and relevant oenological parameters in the must showed R2>0.8 and MAPE<20 %. • Anthocyanin polymerisation and transfer of compounds to the lees was modelled.
Novel application of silica materials to reduce phenolic content of red wines Alessandro Manzoni, Sara Muñoz-Pina, Édgar Pérez-Esteve, Victoria Lizama, María J. García, Angel Argüelles, Jose Luis Aleixandre-Tudo Applied Food Research, 2024 • Thiol and amine functionalized silica materials interact with wines phenolics. • Amine functionalized material showed less affinity for anthocyanins. • The materials interact differently between different phenolics families. • Thiol functionalized silica material can remove up to 30 % of tannins. Phenolic compounds are responsible for the most critical attributes of red wine quality. Structural changes at the molecular level influence the ability of phenolics to contribute to the colour, astringency, and bitterness of the wines. Modulating the phenolic content of red wines might lead to improved mouthfeel properties and enhanced quality. A novel approach using hybrid organic-inorganic systems in the form of functionalised silica materials able to reduce target molecules is presented in this work. Therefore, this study investigates the ability of amine and thiol functionalised silica materials to reduce red wine phenolic content. For this, wines made with Cabernet Sauvignon and Bobal grapes harvested at two different ripening levels were used. Silica fumed was functionalised with two trialkoxysilane derivatives exhibiting thiol or amine moieties. The results showed the ability of the amine and thiol functionalised silica materials to reduce the phenolic content of the wines produced. The anthocyanin and tannin content showed a 30.7 % and 20.9 % reduction in Cabernet Sauvignon wines made with riper grapes and treated with the thiol functionalised material. Moreover, the amine functionalised material caused a 7.4 % and 34.1 % decrease in the anthocyanin and tannin content of Bobal red wines from grapes harvested at the first ripening point. The materials showed varying abilities to interact between the different phenolic families (anthocyanins vs. tannins).
Exploration of Global and Specialized Near-Infrared Calibrations for the Quantification of Nutritional Content in Grapevine Organs, Berry Phenological Stages, and Shoot Lignification Elizma van Wyngaard, Erna Blancquaert, Hélène Nieuwoudt, Jose Luis Aleixandre-Tudo Applied Spectroscopy, 2024 Current infrared spectroscopy applications in the field of viticulture are moving toward direct in-field measuring techniques. However, limited research is available on quantitative applications using direct measurement of fresh tissue. The few studies conducted have combined the spectral data from various cultivars, growing regions, grapevine organs, and phenological stages during model development. The spectral data from these heterogeneous samples are combined into a single data set and analyzed jointly during quantitative analysis. Combining the spectral information of these diverse samples into a global data set could be an unsuitable approach and could yield less accurate prediction results. Spectral differences among samples could be overlooked during model development and quantitative analysis. The development of specialized calibrations should be considered and could lead to more accurate quantitative analyses. This study explored a model optimization strategy attempting global and specialized calibrations. Global calibrations, containing data from multiple organs, berry phenological, and shoot lignification stages, were compared to specialized calibrations per organ or stage. The global calibration for organs contained data from shoots, leaves, and berries and produced moderately accurate prediction results for nitrogen, carbon, and hydrogen. The specialized calibrations per organ yielded more accurate calibrations with a coefficient of determination in validation (R2val) at 90.65% and a root mean square error of prediction (RMSEP) at 0.32% dry matter (DM) for the berries’ carbon calibrations. The leaves and shoots carbon calibrations had R2val and RMSEP at 84.99%, 0.34% DM, and 90.06%, 0.37% DM, respectively. The specialized calibrations for nitrogen and hydrogen showed similar improvements in prediction accuracy per organ. Specialized calibrations per phenological and lignification stage were also explored. Not all stages showed improvement, however, most stages had comparable or improved results for the specialized calibrations compared to the global calibrations containing all phenological or lignification stages. The results indicated that both global and specialized calibrations should be considered during model development to optimize prediction accuracy.
Arabinogalactan proteins and polysaccharides compete directly with condensed tannins for saliva proteins influencing astringency perception of Cabernet Sauvignon wines Brock Kuhlman, Jose Luis Aleixandre-Tudo, John P. Moore, Wessel du Toit Food Chemistry, 2024 Wine astringency is thought to be due to salivary protein precipitation; however, the actual mechanism is not well-defined. This study aimed understand the relationship between whole polysaccharide extracts, produced with and without enzyme maceration, and the saliva protein-tannin precipitation reaction. Polysaccharides were analyzed in the context of salivary protein–tannin interactions using gel electrophoresis, quantitative 1H proton nuclear magnetic resonance (qHNMR), size separation chromatography, immunochemistry, and sensory analysis. Polysaccharide addition reduced saliva protein concentration in tannin-saliva protein-polysaccharide mixtures, indicating that native-wine polysaccharides compete with condensed tannins for salivary protein as ligand partners. qHNMR showed that tannin levels were increased by adding polysaccharides, suggesting that in these conditions, polysaccharides interact with saliva proteins via competitive protein-polysaccharide complex formation. Polysaccharides from non-enzyme-treated wines had threshold concentration of 121 mg/mL versus 86 mg/ml for enzyme-treated as detected by a sensory panel. Enzyme-treated polysaccharides changed astringency perception at a lower concentration than non-enzyme-treated polysaccharides.
Role of caffeic acid in winemaking Caffeic Acid Biological Properties Structure and Health Effects, 2015
Effect of skin contact before and during alcoholic fermentation on the chemical and sensory profile of South African Chenin blanc white wines South African Journal of Enology and Viticulture, 2015
Direct quantification of red wine phenolics using fluorescence spectroscopy with chemometrics I Dos Santos, G Bosman, JL Aleixandre-Tudo, W du Toit Talanta 236, 122857 , 2022 2022 Citations: 47
Renewable energies: Worldwide trends in research, funding and international collaboration JL Aleixandre-Tudó, L Castelló-Cogollos, JL Aleixandre, ... Renewable energy 139, 268-278 , 2019 2019 Citations: 145
Spectroscopy for Phenolic Compounds Quantification in JL Aleixandre-Tudo, W Du Toit Frontiers and new trends in the science of fermented food and beverages, 25 , 2019 2019 Citations: 204
Phenolic profiling of grapes, fermenting samples and wines using UV-Visible spectroscopy with chemometrics JL Aleixandre-Tudo, H Nieuwoudt, A Olivieri, JL Aleixandre, W du Toit Food control 85, 11-22 , 2018 2018 Citations: 103
Chemometric compositional analysis of phenolic compounds in fermenting samples and wines using different infrared spectroscopy techniques JL Aleixandre-Tudo, H Nieuwoudt, JL Aleixandre, W du Toit Talanta 176, 526-536 , 2018 2018 Citations: 80
Spectrophotometric analysis of phenolic compounds in grapes and wines JL Aleixandre-Tudo, A Buica, H Nieuwoudt, JL Aleixandre, W du Toit Journal of agricultural and food chemistry 65 (20), 4009-4026 , 2017 2017 Citations: 220
Trends in scientific research on climate change in agriculture and forestry subject areas (2005–2014) R Aleixandre-Benavent, JL Aleixandre-Tudó, L Castelló-Cogollos, ... Journal of cleaner production 147, 406-418 , 2017 2017 Citations: 148
Mapping the scientific research in organic farming: a bibliometric review JL Aleixandre, JL Aleixandre-Tudó, M Bolaños-Pizarro, ... Scientometrics 105 (1), 295-309 , 2015 2015 Citations: 78
Robust ultraviolet–visible (UV–Vis) partial least-squares (PLS) models for Tannin quantification in red wine JL Aleixandre-Tudo, H Nieuwoudt, JL Aleixandre, WJ Du Toit Journal of agricultural and food chemistry 63 (4), 1088-1098 , 2015 2015 Citations: 47
Effect of the prefermentative addition of copigments on the polyphenolic composition of Tempranillo wines after malolactic fermentation I Álvarez, JL Aleixandre, MJ García, V Lizama, JL Aleixandre-Tudó European Food Research and Technology 228 (4), 501-510 , 2009 2009 Citations: 77
MOST CITED SCHOLAR PUBLICATIONS
Spectrophotometric analysis of phenolic compounds in grapes and wines JL Aleixandre-Tudo, A Buica, H Nieuwoudt, JL Aleixandre, W du Toit Journal of agricultural and food chemistry 65 (20), 4009-4026 , 2017 2017 Citations: 220
Spectroscopy for Phenolic Compounds Quantification in JL Aleixandre-Tudo, W Du Toit Frontiers and new trends in the science of fermented food and beverages, 25 , 2019 2019 Citations: 204
Trends in scientific research on climate change in agriculture and forestry subject areas (2005–2014) R Aleixandre-Benavent, JL Aleixandre-Tudó, L Castelló-Cogollos, ... Journal of cleaner production 147, 406-418 , 2017 2017 Citations: 148
Renewable energies: Worldwide trends in research, funding and international collaboration JL Aleixandre-Tudó, L Castelló-Cogollos, JL Aleixandre, ... Renewable energy 139, 268-278 , 2019 2019 Citations: 145
Phenolic profiling of grapes, fermenting samples and wines using UV-Visible spectroscopy with chemometrics JL Aleixandre-Tudo, H Nieuwoudt, A Olivieri, JL Aleixandre, W du Toit Food control 85, 11-22 , 2018 2018 Citations: 103
Chemometric compositional analysis of phenolic compounds in fermenting samples and wines using different infrared spectroscopy techniques JL Aleixandre-Tudo, H Nieuwoudt, JL Aleixandre, W du Toit Talanta 176, 526-536 , 2018 2018 Citations: 80
Mapping the scientific research in organic farming: a bibliometric review JL Aleixandre, JL Aleixandre-Tudó, M Bolaños-Pizarro, ... Scientometrics 105 (1), 295-309 , 2015 2015 Citations: 78
Effect of the prefermentative addition of copigments on the polyphenolic composition of Tempranillo wines after malolactic fermentation I Álvarez, JL Aleixandre, MJ García, V Lizama, JL Aleixandre-Tudó European Food Research and Technology 228 (4), 501-510 , 2009 2009 Citations: 77
Direct quantification of red wine phenolics using fluorescence spectroscopy with chemometrics I Dos Santos, G Bosman, JL Aleixandre-Tudo, W du Toit Talanta 236, 122857 , 2022 2022 Citations: 47
Robust ultraviolet–visible (UV–Vis) partial least-squares (PLS) models for Tannin quantification in red wine JL Aleixandre-Tudo, H Nieuwoudt, JL Aleixandre, WJ Du Toit Journal of agricultural and food chemistry 63 (4), 1088-1098 , 2015 2015 Citations: 47