Differential Adsorption of Ochratoxin A and Anthocyanins by Inactivated Yeasts and Yeast Cell Walls during Simulation of Wine Aging.

Leonardo Petruzzi,Antonio Bevilacqua,Maria Corbo,Milena Sinigaglia,Antonio De Gianni,Antonietta Baiano

doi:10.3390/toxins7104350

Abstract

The adsorption of ochratoxin A (OTA) by yeasts is a promising approach for the decontamination of musts and wines, but some potential competitive or interactive phenomena between mycotoxin, yeast cells, and anthocyanins might modify the intensity of the phenomenon. The aim of this study was to examine OTA adsorption by two strains of Saccharomyces cerevisiae (the wild strain W13, and the commercial isolate BM45), previously inactivated by heat, and a yeast cell wall preparation. Experiments were conducted using Nero di Troia red wine contaminated with 2 μg/L OTA and supplemented with yeast biomass (20 g/L). The samples were analyzed periodically to assess mycotoxin concentration, chromatic characteristics, and total anthocyanins over 84 days of aging. Yeast cell walls revealed the highest OTA-adsorption in comparison to thermally-inactivated cells (50% vs. 43% toxin reduction), whilst no significant differences were found for the amount of adsorbed anthocyanins in OTA-contaminated and control wines. OTA and anthocyanins adsorption were not competitive phenomena. Unfortunately, the addition of yeast cells to wine could cause color loss; therefore, yeast selection should also focus on this trait to select the best strain.

Highlights

IntroductionThe adsorption of wine components by yeasts, yeast lees, and inactivated yeast fractions is of increasing interest in winemaking, for managing fermentations, wine stabilization, and aging processes [1,2].Several studies have reported on the interaction of yeast cells with a variety of wine compounds, including anthocyanins [3,4,5,6] and flavan 3-ol derivatives [2,7], aromatic substances [1,8], sulfur products [9]or undesirable components, such as octanoic and decanoic acids [10], 4-ethylphenol [11,12,13], geosmin [14], and some pesticides commonly used in vineyards [15].Currently, there is an increasing interest towards yeast adsorption/removal of ochratoxin A (OTA) [16].OTA is a mycotoxin produced as a secondary metabolite by several toxigenic molds belonging to Aspergillus and Penicillum species
The concentrations of ochratoxin A (OTA) in wines with or without treatments with yeasts or yeast cell walls are shown in Table 1; the initial content of toxin was 2 μg/L
The analysis of variance shows the significant influence of the kind of adsorbent, time, and their interactive effect (p < 0.01)

Summary

Introduction

The adsorption of wine components by yeasts, yeast lees, and inactivated yeast fractions is of increasing interest in winemaking, for managing fermentations, wine stabilization, and aging processes [1,2].Several studies have reported on the interaction of yeast cells with a variety of wine compounds, including anthocyanins [3,4,5,6] and flavan 3-ol derivatives [2,7], aromatic substances [1,8], sulfur products [9]or undesirable components, such as octanoic and decanoic acids [10], 4-ethylphenol [11,12,13], geosmin [14], and some pesticides commonly used in vineyards [15].Currently, there is an increasing interest towards yeast adsorption/removal of ochratoxin A (OTA) [16].OTA is a mycotoxin produced as a secondary metabolite by several toxigenic molds belonging to Aspergillus and Penicillum species. The adsorption of wine components by yeasts, yeast lees, and inactivated yeast fractions is of increasing interest in winemaking, for managing fermentations, wine stabilization, and aging processes [1,2]. Undesirable components, such as octanoic and decanoic acids [10], 4-ethylphenol [11,12,13], geosmin [14], and some pesticides commonly used in vineyards [15]. There is an increasing interest towards yeast adsorption/removal of ochratoxin A (OTA) [16]. OTA is a mycotoxin produced as a secondary metabolite by several toxigenic molds belonging to Aspergillus and Penicillum species. It possesses nephrotoxic, immunosuppressive, teratogenic, and carcinogenic (group 2B) properties [17].

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Conclusion