Optimization of in vitro establishment of grapevine varieties for fast micropropagation 

Pinking describes the appearance of a salmon-red blush in white bottled wines produced exclusively from white grape varieties. It is understood as an undesirable chromatic phenomenon by both wine consumers and the industry. Nowadays, there are no treatments to fully reverse pinking once it occurs. Partial reversion has been shown after exposure of pinked wine to ultraviolet (UV) light.

A misconception lingers in the minds of some wine consumers that Champagne wines don’t age. It’s largely a myth, certainly as far as the best cuvees are concerned. Actually, during the so-called autolysis period of time (in the closed bottle, after the “prise de mousse”), complex chemical reactions take place when the wine remains in contact with the dead yeast cells, which progressively bring complex and very much sought-after aromas to champagne. Nevertheless, despite their remarkable impermeability to liquid and air, caps or natural cork stoppers used to cork the bottles are not 100% hermetic with regard to gas transfers. Gas species therefore very slowly diffuse through the cap or cork stopper, along their respective inverse partial pressure. After the “prise de mousse”, because the partial pressure of CO2 in the bottleneck reaches up to 6 bars (at 12 °C), gaseous CO2 progressively diffuse from the bottle to the ambient air
(where the partial pressure of gaseous CO2 is only of order of 0,0004 bar).

Wine quality is influenced by grape maturity, typically monitored by measuring sugar content and acidity.

For the purpose of producing predicate wines in northern part of Croatia, grapes are traditionally left on the vine unpicked. However, grapes on the vine are exposed to unfavorable environmental conditions that affect rapid rotting and attacked by birds. To eliminate the mentioned risks, the grapes can be picked and placed in a protected space (loft, greenhouse, etc.) suitable for drying. This study presents the results of research on withering grapes of the ‘Moscato giallo’ variety in two tretment: sun drying (under covered terrace) and drying in the shade (loft). The following quality parameters were monitored: mass of grapes, sugar concentration, content of total acids, pH, content of organic acids.

During wine production process high attention to the microbiological control from fermentation of the grape must to bottling is necessary. In fact, control of the indigenous microflora of the grape ensures correct fermentation activity of the inoculated starter, while control of the microorganisms in the finished wine is essential to prevent wine spoilage and to ensure the dominance of the desired bacteria when malolactic fermentation is required (Mas and Portillo, 2022).