The use of fungal chitosan as an antiseptic in wine appears as a promising alternative to sulfur dioxide for the elimination of sensitive strains. Nevertheless, its utilization raises the question, "how are the treated wines different from the untreated ones?" Chitosan treatment residues were sought in the oligosaccharide and polysaccharide fractions and among 224 low MW ions (<1800 g·mol) in several wines by using liquid chromatography (size exclusion HPLC or LC-MS) and GC-MS. Standard oenological parameters were also examined as well as possible sensory modifications by a panel of tasters composed of experts and non-experts.
View Article and Find Full Text PDFBiofilms are central to microbial life because of the advantage that this mode of life provides, whereas the planktonic form is considered to be transient in the environment. During the winemaking process, grape must and wines host a wide diversity of microorganisms able to grow in biofilm. This is the case of Brettanomyces bruxellensis considered the most harmful spoilage yeast, due to its negative sensory effect on wine and its ability to colonise stressful environments.
View Article and Find Full Text PDFBrettanomyces bruxellensis is the most damaging spoilage yeast in the wine industry because of its negative impact on the wine organoleptic qualities. The strain persistence in cellars over several years associated with recurrent wine contamination suggest specific properties to persist and survive in the environment through bioadhesion phenomena. In this work, the physico-chemical surface properties, morphology and ability to adhere to stainless steel were studied both on synthetic medium and on wine.
View Article and Find Full Text PDFChitosan is an active highly charged polysaccharide that has initially been developed in oenology to eliminate the spoilage yeast B. bruxellensis. However, different forms of chitosan exist, some complying with EU regulation for their use in wines, others not.
View Article and Find Full Text PDFIn vitro culture of flax ( L.) was exposed to chitosan oligosaccharides (COS) in order to investigate the effects on the growth and secondary metabolites content in roots and shoots. COS are fragments of chitosan released from the fungal cell wall during plant-pathogen interactions.
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