'Cabernet' on the label may reflect a blended wine in that pricey bottle

Buzz: Hey, Marnie, my brother just got back from a trip to Napa Valley. He said some wineries put other grapes in their cabernet sauvignon. Isn't that illegal?

Marnie: No, Buzz, it's legal in most wine regions, as long as it's a small percentage, though in some European regions, the named grape on the bottle must be in the wine 100 percent.

Buzz: Do other places require every grape to be named?

Marnie: Yes. Australia requires all grapes in a wine to be named on the label, in order of volume. But in the United States, a wine made with at least 75 percent of a grape, like cabernet sauvignon, may be labeled as such without mentioning that it is a blend. Cab fans might be surprised to know that half or more of those wines are probably blends.

Buzz: Wait, doesn't that make paying for cabernet a ripoff?

Marnie: Not necessarily. Blending can be motivated by economics, which happens often in low-end wines. Cabernet sauvignon grapes are expensive to grow, so plumping volume with more affordable fruit like zinfandel can improve the bottom line. In the big picture, though, blending grapes is neither good nor bad. It can also be done to improve flavor and quality.

Buzz: Sounds like they're selling hamburger and calling it steak.

Marnie: It depends on what's being blended with the primary grape and why. Some grapes, like pinot noir, always taste best unblended. But others, like cabernet sauvignon, can benefit from blending, provided the added fruit is of equal quality.

Cabernet's shortcoming is that its wines can taste too strong and harsh, so many of the world's best and most expensive cabernets are carefully blended with grapes to balance out these weaknesses.

Buzz: Well, they ought to be mixing it with damn good grapes.

Marnie: The quality-minded vintners do. They usually add grapes that originate from cabernet's native Bordeaux region, like merlot, cabernet franc and petit verdot. Many winemakers firmly believe that cabernet sauvignon needs to be made in the "Bordeaux Blend" style to reach its greatest potential. Other vintners and wine drinkers like how it tastes in its pure form, too.

Buzz: So wine is just like life. Sometimes the impure are as good as the pure.

Marnie Old is a local sommelier and wine author. Check her out at MarnieOld.com or on Twitter at @MarnieOld. Buzz's musings are interpreted by Gar Joseph.