Gustavo Cordero-Bueso

Universidad de Cádiz | UCA · Department of Biomedicine, Biotechnology and Public Health

The EC 2019/187 shows the rules for the usage of ethyl alcohols to fortify wines. These must be obtained from products derived from agriculture and the use of alcohols of mineral or chemical origin is not authorized. The ethyl alcohols authorized for the fortification in the D.O. Sherry have wine origin. But, there are other alcohols that could be...

During alcoholic fermentation, the yeasts responsible for the process produce various metabolites, including urea. The reaction of urea with ethanol spontaneously generates ethyl carbamate in wine, a carcinogenic metabolite whose concentration needs to be regulated. Yeasts produce urea during the arginine metabolic pathway. For this purpose, adapti...

Biological ageing is an essential process for obtaining some distinctive Sherry wines, such as Fino and Manzanilla. It occurs after the fermentation of the grape must due to the appearance of a biofilm on the surface of the wine called “veil of flor”. Yeasts belonging to the Saccharomyces cerevisiae species mainly comprise such biofilm. Although ot...

Yeast selection for the wine industry in Spain started in 1950 for the understanding of the microbial ecology, and for the selection of optimal strains to improve the performance of alcoholic fermentation and the overall wine quality. This process has been strongly developed over the last 30 years, firstly on Saccharomyces cerevisiae, and, lately,...

Vitis vinifera L. ssp. sylvestris (Gmelin) Hegi is recognized as the dioecious parental generation of today’s cultivars. Climatic change and the arrival of pathogens and pests in Europe led it to be included on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species in 1997. The present work focused on the study of...

There is growing interest in yeast selection for industrial fermentation applications since it is a factor that protects a wine’s identity. Although it is strenuous evaluating the oenological characteristics of yeasts in selection processes, in many cases the most riveting yeasts produce some undesirable organoleptic characteristics in wine. The ai...

For thousands of years, humans have exploited the natural process of fermentation of various foods to preserve them, and to enjoy the changes in the sensory characteristics that could be produced. [...].

In view of the growing concern about the impact of synthetic fungicides on human health and the environment, several government bodies have decided to ban them. As a result, a great number of studies have been carried out in recent decades with the aim of finding a biological alternative to inhibit the growth of fungal pathogens. In order to avoid...

The extensive use of synthetic fertilizers and pesticides has negative consequences in terms of soil microbial biodiversity and environmental contamination. Faced with this growing concern, a proposed alternative agricultural method is the use of microorganisms as biofertilizers. Many works have been focused on bacteria, but the limited literature...

: This study investigates the effects of simultaneous inoculation of a selected Saccharomyces cerevisiae yeast strain with two different commercial strains of wine bacteria Oenococcus oeni at the beginning of the alcoholic fermentation on the kinetics of malolactic fermentation (MLF), wine chemical composition, and organoleptic characteristics in c...

Certain acetic and lactic acid bacteria are major causes of quality defects in musts and wines, giving rise to defects such as a “vinegary,” “sharp, like nail polish-remover” taste or preventing alcoholic and/or malolactic fermentation. Sulfur dioxide is the major tool currently used in the control of these bacteria in wine. The aim of this work wa...

Biological ageing occurs after fermentation of the grape must and it is due to the appearance of a biofilm on the surface of the wine called “veil of flor”. Yeast involved in veil formation are mainly Saccharomyces cerevisiae and they have traditionally been divided into four races according to their ability to metabolize different sugars. The grow...

Acetic and some lactic acid bacteria are the main reason for the loss of quality of musts and wines, giving rise to defects such as “vinegary”, “chopped” or preventing alcoholic and / or malolactic fermentation. The solution to this problem consists in the application of authorized bactericidal agents, such as sulfurous. The aim of this work is to...

The principal role of wine yeast is to transform efficiently the grape-berries' sugars to ethanol, carbon dioxide, and other metabolites, without the production of off-flavors. Wine yeast strains are able to ferment musts, while other commercial or laboratory strains fail to do so. The genetic differences that characterize wine yeast strains in con...

Yeasts involved in veil formation during biological ageing of Sherry wines are mainly Saccharomyces cerevisiae, and they have traditionally been divided into four races or varieties: beticus, cheresiensis, montuliensis and rouxii. Recent progress in molecular biology has led to the development of several techniques for yeast identification, based o...

The increasing level of hazardous residues in the environment and food chains has led the European Union to restrict the use of chemical fungicides. Thus, exploiting new natural antagonistic microorganisms against fungal diseases could serve the agricultural production to reduce pre- and post-harvest losses, to boost safer practices for workers and...

¿Cuándo comenzamos a consumir ciertos alimentos?, ¿en qué basamos nuestras preferencias a la hora de consumirlos?, ¿cómo ha cambiado la manera en que nos relacionamos con ellos?, ¿por qué nos provocan-de manera consciente o inconsciente-atracción o rechazo?, ¿de dónde surge la necesidad de describirlos, de cuantificarlos o de conocer sus propiedade...

Wine industry needs a simple method for rapid diagnosis of the dominance of inoculated strains that could be performed routinely during the fermentation process. We present a suitable, high-throughput, and low-cost method to monitor rapidly the dominance of inoculated yeast strains in industrial fermentations of red and white wines using an activat...

Vitis vinifera L. ssp. Sylvestris(Gmelin) Hegi is recognized as the dioecious parental generation of today's cultivars. Climatic change and the arrival in Europe of pathogens and pests have led it to be included on the IUCN Red List of Threatened Species in 1997. At best of our knowledge, no studies on microbial populations of grape-berry surfaces...

Adaptation to changes in osmolarity is fundamental for the survival of living cells, and has implications in food and industrial biotechnology. It has been extensively studied in the yeast Saccharomyces cerevisiae, where the Hog1 stress activated protein kinase was discovered about 20 years ago. Hog1 is the core of the intracellular signaling pathw...

Malvar grape juice offers relatively little in the way of a sensory experience. Our interest lies in the use of locally-selected yeast strains in experimental fermentations to improve the sensory characteristics of Malvar wines. Two locally-selected strains of Saccharomyces cerevisiae were used as starter cultures in vinifications and compared with...

Entre las diferentes fuentes de estrés a las que están sometidas las células de S. cerevisiae durante las primeras etapas de la fermentación alcohólica destaca el estrés osmótico, debido a las grandes cantidades de azúcar del mosto de uva. Éste es de hecho uno de los factores ambientales limitantes del crecimiento de las levaduras que más se han es...

This work seeks to obtain valuable products through an integral exploitation of lignocellulosic residues generated by agriculture, such as olive tree prunings. These sorts of residues are studied as alternative sources for lignocellulosic raw material in the paper industry and the black liquors generated could be used for several purposes, includin...

Wine production in most countries is based on the use of commercial strains leading to the colonisation of the wineries and vineyards by these strains with the consequent reduction of autochthonous biodiversity. This implies that wine styles could become standardised. Exploiting autochthonous yeasts present in grape must is re-emerging as a commerc...

Aplicación del Análisis Sensorial de los Alimentos en la Cocina y en la Industria Alimentaria En nuestro país, aún existe un vacío de conocimiento sobre la utilidad y aplicación del Análisis Sensorial. Como objetivo principal se tratará de acercar a los participantes en el presente curso el Análisis Sensorial de los Alimentos en dos de sus princi...

Acetic acid, a byproduct formed during yeast alcoholic fermentation, is the main component of volatile acidity (VA). When present in high concentrations in wine, acetic acid imparts an undesirable 'vinegary' character that results in a significant reduction in quality and sales. Previously, it has been shown that saké yeast strains resistant to the...

Non-Saccharomyces yeast species assume an important role in wine flavour. Notwithstanding, the chemical basis for the flavour characteristics of wines from some grape varieties is not yet defined. The value of this work lies in the use of Malvar white grape, an autochthonous variety from Madrid (Spain) winegrowing region to conduct spontaneous ferm...

Analysis of the diversity and distribution of wine yeasts isolated from organically and conventionally grown grapes, and during the subsequent fermentation with or without starter cultures in six different commercial wineries. PCR-RFLP screening of isolates revealed the involvement of ten different species. Saccharomyces cerevisiae, scarcely isolat...

Some oenological practices, such as the massive utilisation of commercial yeast and the consequent colonisation of wineries, can contribute to reducing the native yeast biodiversity. In this context, the vineyard could be a reservoir of autochthonous yeasts of oenological interest. Thus, the evaluation of the influence of different agricultural par...

The use of commercial wine yeast strains as starters has been grown extensively over the past three decades. Wine yeasts are annually released in winery environments; however, little is known about the fate of these strains in the vineyard. To evaluate the industrial starter yeasts' ability to survive in nature and become part of the natural microb...

Wine production in most countries is based on the use of commercial strains leading to the colonisation of the wineries by these strains with the consequent reduction of autochthonous biodiversity. This implies that wine styles could therefore become standardised. The vineyard could be an important source of native yeasts of oenological interest. F...

In order to select yeasts with beta-glycosidase activity, 156 non-Saccharomyces yeasts have been analyzed, 83 was isolated in the vineyard under two forms of biological defence, organic and conventional culture, and 73 strains came from the IMIDRA collection. The yeasts with the higher beta-glucosidase activity were isolated under organic culture c...