Well, this is a timely question: Susan wants to know what “Brix” means.
The small instrument you saw at the beginning is called a refractometer. It’s a prism-like instrument that measures the soluble solids in the grape juice, 90% of which is sugar.
Have you ever tasted just-picked wine grapes? Soooo sweet!
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Refractometer? Yup. It plays a very important role, now, as harvest approaches because it measures the sugar in the grapes.
The refractometer is a really nifty little instrument because it gives the winemaker an instant sugar reading. It’s kind of like a prism and measures the soluble solids in the grape juice. All you have to do is squeeze a little juice onto the lens of the refractometer. When you hold it up to the light it measures how much the light bends as it passes through the liquid. The denser the liquid, the more the light bends and the higher the reading will be (about 90% of the soluble solids is sugar).
Why is the sugar so important? It determines the alcohol. The winemaker can assume that a little over half of the sugar measured at harvest will result in alcohol in the finished, dry wine. So, if the grape sample measures 25% sugar the wine will be in the ballpark of 13.5 – 14% alcohol.
Incidentally, the degrees Brix, another wine word, translates to the percentage of sugar. 25 degrees brix = 25% sugar. So, you got a two-fer!
Other important components? Continue reading
This excursion into the world of wine components was started by a question from an A Million Cooks listener. Jim said that, while his friends seem to pick out aromas like strawberry or vanilla, the wine just smells like wine to him!
Today: Alcohol – without it, it’s just grape juice!
During wine making, yeast cells consume the sugar in the grape juice and convert it to alcohol, carbon-dioxide gas and heat – it’s called fermentation. When the yeast runs out of sugar it dies, or goes dormant, the fermentation ends naturally and the wine is dry (not sweet). The higher the sugar content of the grape juice, the higher the alcohol in the wine (assuming it’s dry). There are numerous ways to make sweet wine and, in most cases, it’s done by preventing the yeast from using up all of the sugar. This means there’s natural sugar left over – the wine tastes sweet and the alcohol is a bit lower.
Alcohol accounts for most of the “body” or heft of the wine, along with the grape extracts. Full-bodied wines are usually at least 11.5%. That’s most of the world’s reds and a lot of the world’s Chardonnays. Light-bodied wines are, generally, less than 11%. If you’ve never tasted a wine below 11%, they can be oh, so delightful! Less body doesn’t necessarily translate to less flavorful wine. Continue reading