http://hdl.handle.net/10498/6781 Thu, 05 Nov 2026 13:32:04 GMT 2026-11-05T13:32:04Z http://hdl.handle.net/10498/36616 Development of a chemical model to predict the doses of calcium sulfate and tartaric acid to acidify musts in Sherry area Gómez, J.; Palacios Santander, José María; Lasanta Melero, Cristina; Cubillana Aguilera, Laura; Arnedo, R.; Casas, J. A.; Amilibia, B.; LLoret, I. Calcium sulfate is normally used as a complementary acidifier combined with tartaric acid. The doses corresponding to each one depend on the desired reduction of pH and on the composition of musts. However, considering that there are several interrelated chemical equilibria implied (tartaric acid dissociation, calcium tartrate and potassium bitartrate precipitation, etc.), it is not easy to predict the effect on pH of a mixed tartaric acid and calcium sulfate addition and to determine the necessary doses to reach the final pH required by the winemaker. In a model previously developed by the authors, the prediction of pH after an acidification was properly achieved. On the contrary, in the same model the prediction of the necessary doses of acidifiers to achieve a desired pH have higher errors due to some parameters, as pH and pK, are found as exponential functions in the equations. This work develops and verify the necessary corrections to the models so that appropriate predictions of the doses are obtained. With these corrections, prediction errors of less than 5% were obtained for all doses of acidifiers, confirming the good comprehension of the chemical equilibria involved in this practice. Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10498/36616 2017-01-01T00:00:00Z http://hdl.handle.net/10498/32688 Elaboración de vinos de crianza biológica de grado alcohólico reducido en el sur de España. Resultados actuales y perspectivas de futuro Lasanta Melero, Cristina; Moreno, Juan; Muñoz-Castells, Raquel; Arnedo, Rafael; Medina, Paola; Villa, Miguel; Gómez, Juan Biological ageing wines from the south of Spain, produced into three Origin Denominations (JerezXères-Sherry; Manzanilla de Sanlúcar, Montilla- Moriles and Condado de Huelva) are high-quality products recognized throughout the world. These wines, called Finos and/or Manzanillas, are usually fortified up to 15%- 16% v/v alcohol to carry out the aging under the characteristic “flor velum”. The wine consumption model is changing and consumers are looking for products with a high sensory quality but with a moderate alcohol content. In this sense, it is very interesting for the sector to elaborate biological ageing wines with the same quality but with low alcohol levels (13,5-14,5% v/v). In the present work, the results of conducting biological ageing, both static and dynamic, with lower than usual alcoholic degrees (13.5-14.5% v/v) are shown, in three wineries of the Sherry area, and working on two different scales. In addition, some tastings have been carried out with consumers to preliminarily assess the possible acceptance of these wines in the market. The first results indicate that it is feasible to work at an alcoholic degree somewhat lower than usual without affecting the normal activity of the flor yeasts or the quality of these wines. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/10498/32688 2023-01-01T00:00:00Z http://hdl.handle.net/10498/32687 Utility of agroclimatic stations to characterize microclimate and climate change in the sherry area over the last 20 years Gómez Benítez, Juan In this work we analyze climatic data of temperatures, rainfall, winds and bioclimatic indexes for the last 20 years obtained from 8 agroclimatic stations distributed in the cultivation areas of the Sherry. The effects of climate change have been confirmed and maximum temperatures show a clear tendency to increase, which could lead to a considerable increase in maximum temperatures in the coming years. It has been observed that the average maximum temperatures during the summer in Jerez exceed 32 ºC, while in El Puerto and Sanlúcar they are appreciably cooler and are in the order of 30.5 ºC. It has also been verified a reduction of rainfall by almost 100 L/m2 in recent years, and verifying that rainfall has a certain cyclical character. It has been tested that predominant winds in Jerez are from the east, in Sanlúcar they are from the west and El Puerto has an intermediate wind regime. Significant differences have been observed between climatic stations located at short distances, showing the convenience of having agroclimatic stations in the most important vineyard areas and in the most suitable areas of the winery districts of the cities to adequately characterize their microclimate in relation to the wine industry. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/10498/32687 2023-01-01T00:00:00Z http://hdl.handle.net/10498/32635 New types of organic wines with Pedro Ximenez variety grown in the Marco de Jerez Sherry region Sancho Galán, Pau; Amores Arrocha, Antonio; Pérez González, Juan Manuel; Gutiérrez Gordillo, Sarai; Palacios Macías, Víctor Manuel; Jiménez Cantizano, Ana Concepción The Pedro Ximénez grape variety is one of the authorised varieties in the Jerez-Xérès-Sherry DO, although it currently occupies only 1% of the region's total cultivated area. With the intention of promoting its cultivation, as well as diversifying production in a historic wine-growing area such as the Marco de Jerez (Spain), work is currently being carried out through a research project in which both public and private entities are participating. This project focuses, among other aspects, on the organic cultivation of this minor grapevine variety in the region, as well as on the production of naturally sweet wines. In this research, the results of the characterisation of the grape musts of overripe Pedro Ximénez grapes are presented, as well as the monitoring of its fermentation and the characterisation of the wines obtained. The resulting wines show how the overripening technique is presented as a viable alternative for the production of new types of wines in a warm climate area such as the Marco de Jerez. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/10498/32635 2023-01-01T00:00:00Z