Marketing terroir wines

Laccases from lactic acid bacteria (LAB) are described as multicopper oxidase enzymes with copper union sites. Among their applications, phenolic compounds’ oxidation and biogenic amines’ degradation, have been described. Besides, the role of LAB in the toxicity reduction of ochratoxin A (OTA) has been reported (Fuchs et al., 2008; Luz et al., 2018). Fungal laccases, but not bacterial laccases, have been screened for OTA and mycotoxins’ degradation (Loi et al., 2018). OTA is a mycotoxin produced by some fungal species, such as Penicillium and Aspergillus sp., which infect grape bunches used for winemaking.

The gustatory balance of wines relies on sweetness, bitterness and sourness. In dry wines, sweetness does not result from the presence of residual sugar as in sweet wines, but is due to other non-volatile compounds. Such taste-active compounds are released during winemaking, by grapes, yeasts or oak wood and belong numerous chemical families [1]. Beyond this diversity, stereochemistry of molecules can also influence their sensory properties [2]. However, the molecular determinants associated with this taste have only been partially elucidated. Astilbin (2R, 3R) was recently reported to contribute to wine sweetness [3]. As its aglycon contains two stereogenic centers, three other stereoisomers may be present: neoisoastilbin (2S, 3R), isoastilbin (2R, 3S), and neoastilbin (2S, 3S). These compounds have already been observed in natural products, but never in wine. This work aimed at assaying their presence for the first time in wines as well as their taste properties.The isomers were synthesized from astilbin and purified by semi-preparative HPLC.

Limited information is available on grape wall-derived polymeric structure/composition and how this changes during fermentation. Commercial winemaking operations use enzymes that target the polysaccharide-rich polymers of the cell walls of grape tissues to clarify musts and extract pigments during the fermentations. In this study we have assessed changes in polysaccharide composition/ turnover throughout the winemaking process by applying recently developed cell wall profiling approaches to both wine and pomace polysaccharides. The methods included gas chromatography for monosaccharide composition (GC-MS), infra-red (IR) spectroscopy and comprehensive microarray polymer profiling
(CoMPP) using cell wall probes.

Background: Aroma compounds are important secondary metabolite in grapes and play important roles in the flavor and quality of grape berries and their wines. Vitis amurensis grape belongs to the East Asian Vitis spp., with excellent cold and disease resistance, and exhibits strong brewing potential. However, it has not been effectively utilized and there is no systematic research on the aroma compounds of V. amurensis grapes.
Methods: To provide sufficient experimental evidence for the characteristic aroma of V. amurensis grape, HS-SPME-GC/MS was used to identify the aroma compounds of five V. amurensis (‘Beiguohong’, ‘Beiguolan’, ‘Shuangfeng’, ‘Shuanghong’, ‘Shuangyou’) and three interspecific hybrids (‘Beibinghong’, ‘Xuelanhong’, ‘Zuoyouhong’) grapes in Zuojia and Ji’an. The grape berries were collected at harvest in 2020, 2021 and 2022.

The aim of this work was to evaluate the effect of preharvest application in Monastrell berries using two different types of applications: conventional treatments