How does the type of grape affect the taste of the wine?
The type of grape affects the taste of the wine because of the tannins. Tannins are found in the skin and seeds of grapes and they give wine its astringency. The amount of tannins in a wine is determined by the grape variety and the winemaking process. For example, Cabernet Sauvignon wines are high in tannins because the grape skin is thin and the seeds are bitter. Merlot wines have less tannins because the grape skins are thicker. The type of grape also affects the color of the wine.
How do wine makers know when the grapes are ready to be picked?
The ripeness of wine grapes is determined by a number of factors, the most important of which are sugar, acid and tannin levels. Sugar is what will eventually be converted into alcohol, so the more sugar in the grapes, the higher the potential alcohol level in the wine. Acidity provides balance and freshness, and tannins give structure and aging potential.
Grape growers and winemakers measure ripeness in a number of ways, the most common of which are Brix, pH and titratable acidity. Brix is a measure of sugar levels, and is typically around 20-25 for most wines. pH is a measure of acidity, and wines usually fall in the range of 2.9-3.9. Titratable acidity is a measure of the total acidity in the grape, and is usually around 5-8 g/L for most wines.
The decision of when to pick grapes is ultimately up to the grower or winemaker, as they know their vineyard and wines best. However, there are some general guidelines that are followed. For white wines, grapes are usually picked when they are at or just before full ripeness, as too much sugar can result in wines that are too high in alcohol and lack acidity. For red wines, grapes are usually picked when they are at or just before full ripeness, as the tannins in the grapes need time to soften.
Ultimately, the decision of when to pick grapes is a balance of sugar, acid and tannin levels, as well as the desired style of wine. Growers and winemakers will use their knowledge of the vineyard, the grapes and the wine they want to make to determine when the grapes are ready to be picked.
Visit howtomakewinefromgrapes.com to learn more about making wine from grapes. Disclaimer: We used this website as a reference for this blog post.