of the sugar
content of liquid
s, developed by A.F.W. Brix
. Brix is officially express
ed in degree
s, but very often the degree symbol
is dropped. Each degree of brix represents one gram
of sugar per 100g of liquid. Thus, a liquid
with a brix
of 25 contains 25 grams
of sugar for every 100g.
Brix measurement is an important tool in winemaking, as it can be used to determine the sweetness of grapes and grape juice. It is used prior to harvest to help choose the best time to pick the grapes; most grapes for table wines are harvested at levels of 21-25 brix. If grapes are harvested at a lower brix, the resulting grape juice may be too acidic and require chaptalization* (the adding of supplemental sugar to the fermenting juice). If grapes are harvested at a higher brix, the resulting grape juice may lack the acidity needed for a balanced wine, and may require acidification (the adding of supplemental acids).* Moreover, high-brix grapes may produce a wine with unacceptable levels of residual sugar, which (unless it's a dessert wine) may also throw off the taste.
Since yeast gradually converts the sugars in grape juice into alcohol, measuring brix also helps keep track of the fermentation process. Over the course of fermentation, about 55-60% of the sugars in grape juice will be transformed into alcohol, and therefore the level of brix at harvest can be an indicator of the final alcohol content of the finished wine. The accepted conversion factor is 0.55; therefore, if the grapes on the vine display a brix of 25, their "potential alcohol" is 13.75% (25/0.55).
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in some areas, which can make the wine grower
's job that much more challenging