Optimizing the Process of Making Sweet Wines To Minimize the Content of Ochratoxin A

Abstract

During the drying process of raisins, the grapes are subjected to climatic variations that can result in heavy infections of some fungal species that produce ochratoxin A (OTA), a powerful toxic metabolite, whose maximum permitted content is set by the European Union at 2.0 μg/L for grapes, wine and other drinks derived from the grape. The aim of this paper is to optimize the process of making sweet wines in order to minimize the content of ochratoxin A. The results reflect a reduction of the OTA content in grapes dried under controlled conditions in a climatic chamber up to 24% compared to those sunned in the traditional way. A decrease of the concentrations of OTA is also observed during the processes of vinification. Those wines with prefermentative maceration reached a higher OTA content than the wines without maceration, but unexpectedly were not those preferred from a sensorial point of view. In addition, the process of aging in oak casks has been shown to serve as a natural method for reducing the OTA content of these wines.

Colour and phenolic compounds in sweet red wines from Merlot and Tempranillo grapes chamber-dried under controlled conditions

“…This has promoted the development of alternative methods of fruits drying under controlled temperature and humidity conditions; such methods produce raisins of a similar quality to those obtained by sun-drying but in less time (Serratosa et al, 2008b). These fruits include cherries, figs, apricots or even raisins (Doymaz, 2006) for the production of sweet wines (Ruiz Bejarano, Rodriguez Dodero, & Barroso, 2010).…”

Volatile composition of Pedro Ximénez and Muscat sweet Sherry wines from sun and chamber dried grapes: a feasible alternative to the traditional sun-drying

“…This traditional process is affected by the attack of insects and possible rainfall. This leads to growth of fungi which resulted in loss of high amount of grapes and give rise to the formation of toxins in the wine (Valero et al 2008;Ruíz Bejarano et al 2010).…”

“…Alternative to this traditional sun-drying methodology, that avoids the problems of fungi and insects, has been developed. It is being used for the drying of horticultural products, in general, and grapes, in particular, and consists in forcing the loss of water by means of forced convection with hot air in drying chambers (Vega-Mercado et al 2001;Ruíz Bejarano et al 2010;Serratosa et al 2014). Ruiz et al (2009) found that the musts from chamberdried grapes from Pedro Ximenez exhibited similar volatile profiles than those obtained from sun-dried grapes.…”

The Fate of Mycotoxins during the Distillation Process of Barley Shochu, a Distilled Alcoholic Beverage

“…The main raw materials of alcohol beverages are grains and fruits. Hence, brewers consider that mycotoxins pose remarkable risks, but there have been few studies of the fate of mycotoxins in production of alcohol beverages [1][2][3] and, especially as regards distilled beverages, no experimental data have been reported. Meanwhile, in response to increasing consumer demands for food safety, brewers have to present any risks based on experimental data.…”