Some things are way better when combined. This holds true with wine blending. When you mix two types of wine, you get an excellent blend, as long as you get the right ratio for each wine type you're blending. There are also certain varietals that go together really well, either because one gains the other's flavor profile or both of their characteristics complement each other.
There can be quite a few reasons why certain winemakers blend wines, and here are some of them:
Adjust the wine's acidity
Acids are integral components of any wine. Those that have low acidity taste bland and lifeless, while we have those at the other end of the spectrum – those that have high acidity – that taste really sour and sharp. When one type of wine has too much acidity, the taste can be corrected by mixing it with a varietal whose acidity is low.
Improve the color
This reason for blending wine is generally applicable only to reds. When one red wine is too dark and the other is a bit pale, mixing them together adjusts the color. True appreciation of wine involves many of our senses, and it certainly includes the sense of sight. When a good color is achieved, the overall wine-tasting experience becomes surprisingly better.
Enhance the aroma
On their own, some wines already give out excellent odors once you start swirling them inside the glass. However, those who want to achieve a more complex aroma blend certain varietals to achieve just that. For example, Merlot can be blended with certain reds like Cabernet Sauvignon for a better aroma.
Improve the flavor
Certainly, this is one the major reasons why wines are combined. An excellent example of an exquisite blend is when you mix Grenache with Shiraz and layer it with Mourvedre. The resulting blend is a liquid that has a unique complexity of flavor that you'll never taste from a single varietal. The Australia Cabernet Shiraz is another fine resultant of combining the popular reds Cab and Shiraz.
Adjust the tannin levels
Tannins are responsible for giving reds their defined structure. The best analogy that can be used how important tannins are is that they are like the frame that provides support and movement to a human body. They are derived from the stems, skins, as well as the seeds of the grapes that are used to make wines. Blending two or more wines is done to raise or lower the tannin levels and in the process giving the resulting combination a different structure.
If you want to have a wine-tasting experience different from the usual sipping of single varietals, reach for a wine blend next time you head out to your favorite wine shop.