Peptides diversity and oxidative sensitivity: case of specific optimized inactivated yeasts

There is a growing trend on the transition from conventional to agroecological management of vineyards. However, the impact of practices, such as reduced-tillage, organic fertilization and cover crops, is not well-understood regarding the soil microbial diversity, and its relationship with the soil physicochemical properties in the subsurface depth near the rooting zone. Soil bacterial diversity is an important contributor towards plant health, productivity and response to environmental stresses. A field experiment was conducted by sampling subsurface soil bacterial community (NGS and qPCR) near to the root zone of Macabeu and Xarel·lo vineyards, located at the Penedes. 3 organic (ECO) and 3 conventional (CON) vineyards, with more than 10 years of respective management were sampled (n=5 each plot). ECO practices did not affect bacterial and fungal abundance but increased significantly the ammonium oxidizing bacteria and alpha-diversity (Inv.Simpson). Interestingly beta-diversity was significantly affected by the management strategy. ANOSIM-tests revealed a significative effect of the management (ecological vs conventional) and plot, on the soil microbial structure (ASV abundance). Main phyla depicted were Proteobacteria, Actinobacteria and Acidobacteria, whose relative abundances were not affected by the management. EdgeR assay revealed a significant increase of Cyanobacteria and decrease of Gemmatimonadetes and Firmicutes phyla in ECO. Interestingly, the grapevine variety was not correlated with the soil microbial community structure. Mantel-test revealed an important correlation (Spearman) of some physicochemical parameters with the soil microbiota structure, in order of importance: texture, EC, pH Ca/Mg, Mg/P, K+, Mg2+, Ca2+, SO42-, and OM. N-NH4 and NTK, which were higher in the ECO managed soils, did not correlated significantly with the soil microbiome population. The results revealed the importance of combining a deep physicochemical characterization of each replicate with the microbial diversity assessment to gain better insights on the relationship between soil microbiome and vineyard management.

The effect that some extraction techniques, such as ultrasound (Cacciola, Batllò, Ferraretto, Vincenzi, & Celotti, 2013; Povey & McClements, 1988) or microwaves (Carew, Close, & Dambergs, 2015; Carew, Gill, Close, & Dambergs, 2014) produce on the aroma of red wines, when applied to processes of extractive nature, such as pre-fermentative maceration or ageing with oak chips (Spanish oak – Quercus pyrenaica and French oak – Quercus robur) has been studied. The volatile profile was determined by means of gas chromatography coupled with olfactometric and mass spectrometric detection. A sensory analysis was also carried out. No indications were found to show that the pre-fermentative treatment with microwaves or ultrasound modified the sensory profile of the wines whereas the application of such energies during the ageing phase showed some positive trends at sensory level.

Recent regulations concerning alcoholic beverages have prompted producers to revise their product labels to incorporate nutritional information. In this context, qr codes containing such information, known as e-labels, are now being employed on wine labels for the first time.

Riesling wines are appreciated for their diverse aromas, ranging from the fruity fresh characters in young vintages to the fragrant empyreumatic notes developed with aging. Wine tasters often refer to Riesling wines as prime examples showcasing terroir, with their typical aroma profiles reflecting the geographical provenance of the wine. However, the molecular basis of the distinctive aromas of these varietal wines from major Riesling producing regions in Europe have not been fully elucidated. In this study, new lights were shed on the chemical characterization and the sensory contribution of volatile thiols to Riesling wines from Rheingau, Mosel, and Alsace. First, Riesling wines (n = 46) from the three regions were collected and assessed for their aroma typicality by an expert panel.

Aim: In recent times the export of Beaujolais wines has been jeopardised due to a limit of manganese content (Mn) in wine implemented by China (2 mg/L), related to suspicions of potassium permanganate fraud. Nevertheless, soil Mn content may be high in some soil types in Beaujolais. The aim of this study was to improve knowledge of manganese transfer from soil to vine and wine because data on this subject is scarce.