Wine Maturation and Chemicals

Those grapes from precocious maturation, as of Chardonnay, Gewürztraminer and Pinot Noir, harvesting season begin round about mid January, with the harvest framework stretching as far as early February.  In the best of rights for those grapes from intermediary maturation, likewise Italic Riesling and Merlot, the harvest season comes to full-blossom thereabouts late January up until mid February.
As for those grapes of late maturation such as Cabernet Franc, Cabernet Sauvignon and Bianco Muscat, the harvest begins in and around mid February lasting up until late March or thereabouts.
Maturation period stands for the timeframe of a change in color to take place for the berries up until reaching their prime-time for harvesting. It epitomizes sunny days, as sundry and sultry, whereupon the inhibition-process for the grapes’ rotten occurs, enabling henceforth the harvest to get done by the time the fruits bear skin, kern and peps, in ideal stage of maturation, so that berries become capable of synthesizing and store up more sugars, pigments, tannins as well as aromatic substances and its so-precursors. The vineyard’s absorption process of water, if on a fairly restrictive level, results in fruits with high level of sugars, so-substances both organic and mineral.  The mild temperature weather-wise places effect upon color intensity so does the biochemical metabolism preceding the synthesis of such substances, in which point favored by the balmy temperature, primarily nocturnal. Furthermore, the additional acidity obtained through low temperatures ensures the wines’ ph.

Chemical compounds in wine

Water-85/95%
Alcohols
Ethanol-72/120 g/l
Glycerol 5-10 g/l
Other alcohols: methanol, isopropyl, etc.
Grape acids: tartaric, malic, and citric.

Fermentation acids: succinic, lactic, acetic, butyric, formic, propionic, carbonic.

Sugars: glucose 7 to 15%, fructose, else.
Phenolics-tannins, anthocianins,
Aldehydes, esters, bioflavonoid, amino acids, trace minerals and stabilizers.

INTERESTING LINKS:

Maturing Grapes and Wines - Wine Making