Can soil nitrate explain polyphenol and anthocyanin content in vineyard with similar available soil water regime? 

In temperate climates, such as in the North of Spain, the use of irrigation in the vineyard has not been required, due to the usual rainfall from June to August. In some large vineyards, irrigation management has been carried out, based on occasional support irrigation, or for the application of nutrients (fertigation). Currently it is necessary to implement decision support models to manage irrigation water in real time and avoid misuse of a scarce resource. Moreover, quality standards must be achieved, as in the previous rainfed viticulture.

Vineyards from mild temperature, high humidity locations receive often treatments with fungicides to prevent damages produced by fungi responsible for mildium, oidium and botrytis infections. In addition, insecticides are also applied to vineyards to fight again pests, which affect directly, or indirectly (as vectors of different diseases), their productivity. A fraction of the above compounds reaches the soil of vineyards, either during application, or when released from the canopy of vines due to rain-wash-off. Thereafter, depending on soil conditions (pH, organic matter) and environmental variables (regimen of rain, slope of vineyards), they might persist in this compartment, be degraded and/or transferred to water masses, modifying the biodiversity of soils and/or affecting the quality of water reservoirs.

Pomace is one of the main residues generated by the wine industry and represents an environmental problem. Currently, there is a growing interest in the revaluation of these products because different bioactive compounds can be obtained from them, such as polyphenols, grape seed oils and polysaccharides. Red grape pomace can be an important source of polysaccharides, but they are currently little studied and even less with viable and environmental extraction processes (green extraction), such as flash extraction. The residual amount of the fraction rich in pectin (residual pulp) and component rich in hemicellulose in the pomace and the strength of association of the pectin with the cellulose-xyloglucan network depend on the degree of extractability of the polysaccharides in red winemaking and on the winemaking conditions.

Grapevine cultivars are vegetatively propagated to preserve their varietal characteristics. However, spontaneous somatic variations that occur and are maintained during cycles of vegetative growth offer opportunities for the natural improvement of traditional grape cultivars. One advantageous trait for winegrowing is reduced bunch compactness, which decreases the susceptibility to pests and fungal diseases and favor an even berry ripening.

The O2 uptake in the different winemaking processes is generally considered to be negative for the sensory characteristics of white and rosé wines. Wine racking is a critical point of O2 uptake, as the large surface area of the wine exposed during this operation and the inability to maintain an effective inert gas blanket over it.
The objective was to study O2 uptake during the racking of a model wine without using inert gases and to compare it with the purging of the destination tank with different inert gases.