By Hank Johnson:

People sometimes say to me, “I want a sweet wine; I don’t like the puckering feeling in my mouth.” Well, let me explain. First, the puckering feeling comes not from the dryness of the wine, but rather from astringency. The dryness of a wine is determined solely by the amount of natural sugar (or added sugar) in a wine.

At Chaumette, we like to pick our grapes at 22-23% Brix. Brix is a measure of soluble solids of which 99% is natural sugar. By the way, grapes that produce wines have some of the highest amount of natural sugar among all fruits. This is important because the amount of sugar in the grapes determines the amount of sugar in the juice and the amount of sugar determines the amount of alcohol in the wine.

It is interesting to note that different strains of yeast produce differing amounts of alcohol in the fermentation process. We receive catalogs listing, in some cases, up to 100 varieties of yeast. The description includes the amount of alcohol in which the yeast can survive.

Up until about five years ago, we used a factor of 0.54 times the level of sugar in the juice to get a pretty good estimate of the level of alcohol we could expect in the wine. This is important because the amount of alcohol greatly affects the mouthfeel of the wine. A low alcohol wine produces a watery, thin mouthfeel, which is regarded as a flawed wine characteristic. Twelve percent alcohol is viewed as about the lowest acceptable level in most wines.

The production of wine yeast has become a dynamic industry. Much research is going on to create yeasts that produce greater amounts of alcohol from the same juice. We now use a factor of 0.60 rather than 0.54 to estimate the amount of alcohol produced by the new yeast.

In the fermentation process, the yeast “eats” the sugar, produces alcohol and brings the amount of sugar from about 23% to a level of 0/02% or 2/10 of one percent. The wine industry recognizes that human beings can perceive sweetness at about 0.07% and the wines at or below 0.07% are considered DRY WINES.

Back to astringency. The puckering or dryness perceived with some young red wines and others come from one or all of the following: immature grape seeds, crushed during the grape crushing process, some wood barrels or from the grape skin itself. The substance responsible is tannin. This is predominantly what produces the pucker feeling, not the dryness of the wine, which has nothing to do with astringency.

Tannin is not all bad; in fact, some tannins are our friends. Good tannin comes from mature grape seeds, some wood applications and other sources. Good tannins increase the backbone of a wine or the positive strength of the wine. It can add complexity and interest to a wine. It may appeal to your intellectual enjoyment of the wine.

Remember, dryness has nothing to do with astringency. Tannin – more specifically, bad tannins – are what causes astringency.