Plump. They dangle in clusters of honey yellow to sapphire blue orbs, dozens upon dozens stemmed to the meandering vine, brilliant in the sunlight of an orderly vineyard.  Soon it will be time for their harvest when about 25 per cent of their mass will be sugar.  But wait, not all of a grapes sugars are ferment-able! Only the six-carbon sugars of glucose and fructose are metabolized by the yeast(native or select), leaving the tiny minority five-carbon sugars of ribose and xylose un-fermented. There are various advantages and disadvantages for fermentations that use native (wild) vs. designer(cultured) yeasts as a catalyst, such as control over unwanted by-products or a more predictable alcohol productio.

A ripe grapes pulp mass is mostly water and sugar, along with a collection of acids, pigments. proteins, vitamins and minerals. Each will have a part to play in its transformation into wine, but it is the sugars and the acids that have the most important work to do when changing juice into wine. Vitis, the plant genus, and one of its many species, vinifera, is quite widespread, and today is grown on most continents. Throughout history vitis vinifera, a climbing, weak-stemmed vine, consistently has produced the worlds most celebrated and sought-after  wines.  As it has done for others throughout the ages, these vines and their fruits have mysteries to routinely unfold, which I find also cultivated a passion for their wines within me.

Great vineyard sites across the globe do differ in their soil compositions, but all are typically not very fertile, yet have soils that regulate water to their vines.  Such a soil structure enables the roots access to water, but also allows for excess water to be drained away, which allows important oxygen to the roots. Grapevines only require principal soil nutrients of nitrogen(N), phosphorus(P) and potassium(K), along with six minor nutrients. As a result, Great vineyards are generally found around the globes temperate climate zones, near bodies of moderating waters, and between the 30th and 50th parallels in our Northern and Southern hemispheres, Within the worlds viticultural zones, white and red grapes usually require an average summer temperature of about 66 to 70 degrees F to ripen, respectively. The globes temperate climate zones and some of its extremes fill the bill. Here in the sunshine state, suitable vineyards sites are usually classified by their degree days, a scale of five(5) regions summarized by average growing season days of temperatures  above 50 degrees, the California Heat Summation Index.

A grape vines growth cycle awakes from the dormancy of Winter and renews each Spring: bud break, closely followed by flowering, and then berry set from these self-pollinators.  In Summers heat acid production drops and sugars increase, signaled by the color change: veraison, and then weeks later grapes arrive at ripeness/maturity, and then at the perfect time of required balance in the fruit: harvest.  When everything in the vine and vineyard are working together to create the best fruit possible, with managed growth and yields, the vine is said to be in balance. The juice from these grapes is rich in fixed acids, dominated by malic and tartaric acid, and with just enough to produce a balanced wine. Control of these acids is primary in winemaking, because without control, volatile acids like the foul, odorous acetic acid will drastically change the composition of the finished wine.

When all is in balance, the craft of the winegrower and the artistry of the winemaker, the result can be sublime.  It is wine, glorious and mysterious, intensely sharp or richly textured, that has created passions in us for many millennium. And so it remains as it has been.  Wine not!

Salute’