Teran grape quality influenced by different irrigation treatments

The development of interspecific hybrid varieties (ihvs) resistant to diseases such as powdery mildew and downy mildew allows for a decrease in the use of inputs in vineyards. In this pers-pective, ihvs represent a response to societal demand for reducing environmental impact and are increasingly used in viticulture. At the same time, wines resulting from so-called sponta-neous fermentations, based on indigenous flora, have recently gained popularity.

Fungal chitosan is a polysaccharide made up of glucosamine and N-acetyl-glucosamine and derived from chitin-glucan of Aspergillus niger or Agaricus bisporus. Fungal chitosan has been authorized as an antiseptic agent in wine since 2009 (OIV) and in organic wine in 2018. At the maximum dose of 10g/hl, it was shown to eliminate Brettanomyces bruxellensis, the main spoilage agent in red wines. Fungal chitosan is highly renewable, biocompatible (ADI equivalent to sucrose) and non-allergenic. However, winemakers often prefer to use sulfites (SO2), though sulfites are classified as priority food allergens, than chitosan. Indeed, many conflicting reports exist regarding its efficiency and its side effects towards beneficial wine microorganisms or wine taste. These contradictions could be explained by the heterogeneity of the fungal chitosan lots traded, the diversity of the wines (chemical composition, winemaking process), but also, by the recently highlighted huge genetic diversity prevailing in wine microbial species.

The acıkara grape variety, a nearly forgotten native black variety in Anatolia/Turkey, has recently gained interest in its potential for producing high-quality wine from producers and consumers. The potential of producing high-quality red wine from the Acıkara grape variety (vitis vinifera), which is cultivated on the elmalı/antalya in the highland (1100 m altitude) of western mediterranean region, was investigated, and the suitability of the wine’s characteristics associated with high-quality red wine was determined.

Flavonoids, including flavonols, anthocyanins, and tannins, are important contributors to grape and wine quality, and their biosynthesis is strongly influenced by bunch microclimate.

The use of high-power ultrasound (US) during the winemaking process has been extensively studied at laboratory scale in order to demonstrate its possible use to improve the extraction of compounds of interest. However, studies on semi-industrial and industrial scale are needed to confirm this positive effect, since the International Organization of Vine and Wine approved its industrial use in 2019 [1].