There seems not much to say about it except that it's delicious, powerful, fairly easy to grow given long-lasting hot weather for its late ripening season, and that it makes wines of great, masculine class and recognizable quality anywhere it is planted. It also beefs up the attributes of other, thinner wines, and so is the go-to partner for shyer reds, especially in the New World. Oz Clarke writes, in Grapes and Wines:
"King Cab, they call it. King Cab the colonizer, the conqueror. Cab the corrupter of other cultures, laying waste other grape varieties and other wine styles round the world with the brutal power of its broadsword, from Tuscany to Bulgaria, from Chile to Spain.
"Yet at the same time Cabernet Sauvignon is the consumer's friend. It was the first grape to give such upfront flavours to red wine, flavours that were so easy to recognize and admire, that they turned on generations of drinkers who'd never come near a bottle of red before."
The flavors discussed by wine writers generally run to blackberry, black currant, cassis (same as black currant), plum, and in older fine cabernets, cedar wood and cigar box. If you taste something more like green pepper, you have a wine made either of underripe fruits -- that late ripening habit can be a problem if fall comes early -- or, according to Karen MacNeil, simply a poorly made wine (The Wine Bible).
With all due respect to the experience and judgment of these writers, I wonder about the constant comparisons they make, when speaking of cab, to these "black" fruits. When was the last time anyone ever tasted or even saw a black currant? Recently I was able to taste a black currant wine, and the last thing it brought to mind was cabernet sauvignon. I wonder if wine writers are not perhaps swayed by the color of the wine more than anything else. In an older book, Plain Talk about Fine Wine (1984), author and winemaker Justin Meyer suggests sharpening your palate by tasting wine from a black glass. See what you think, he says, when you have no clues about color. It would be a useful experiment. Pretend I'm the teacher, or rather Justin Meyer is, and this is a test question: "what does a cab taste like? -- do not use any visual descriptors." I do not, unlike the poet, drink with mine eyes.
Anyway, cab is king not only for all the above reasons but also for the devolutionary reason that it is one of the prime grapes of Bordeaux, and Bordeaux remains "the motor of the wine world" (Hugh Johnson's Pocket Guide, 2010). "To know wine, you must know French wine, and to know French wine, you must know Bordeaux" (Wine for Dummies, McCarthy and Ewing). The right soil, climate, grapes, and centuries of winemaking experience have all contributed to making Bordeaux incomparable, particularly that left bank, the Haut-Medoc with its famed classed growths, its Latours and Margaux; when you buy an inexpensive, easy-drinking cabernet from Chile or anywhere else, you are buying it because the winemakers there, who can only dream of miraculous Bordelaise style results, are at least testing for themselves the heft of that powerful, consumer-friendly French broadsword.
The grape itself is a child of interesting parents. A generation ago, when Frank Schoonmaker was writing his Encyclopedia of Wine, he said simply that there were two cabernets, our cabernet sauvignon and the more prolific cabernet franc, vinified in France's Loire valley and bearing on its labels, as it still does, Loire place names like Bourgeuil and Chinon. (Are you fond of history? In thinking of the Loire, think King Henry II and Eleanor of Aquitaine, circa 1200, think The Lion in Winter. " 'There's to be a Christmas court. Where?' " " 'At Chinon.' " In those feudal days the Loire was Henry's possession, as Aquitaine to the south was Eleanor's. Come to think of that, Bordeaux was Eleanor's birthplace and her capital.) And -- Schoonmaker explained -- the reader ought not to be confused by the California wine called Ruby Cabernet, made from a single grape, a new cross between a cabernet sauvignon and the lesser known carignan.
Today, Ron and Sharon Herbst are able to state, in The New Wine Lover's Companion, that our King Cab has been discovered to be botanically the natural offspring of Chinon's own cab franc and, curiously, the white (Bordeaux) grape sauvignon blanc. How on earth can a red grape plant and a white grape plant get together and produce a new, red grape that is better -- fuller of all the good flavors, plus the acids and tannins that promote ageworthiness in wine -- than either parent? A botanist I am not, so I can only guess that sometime in the late 1600s, which is when King Cab seems to have appeared in the fields, some enterprising French bee must have gone dashing about pollinating things, and so made us all the happier for it. The good people at the Viticulture and Enology Department, University of California at Davis, are the ones who have demonstrated this, via DNA splicing and mapping and so on. They are wonderful. Oenophiles know that place, incidentally, simply as UC Davis, and it's a holy of holies.
If you want one characteristic of this interesting, this kingly grape child to remember, to help you understand what it does in your glass, remember that cab is the small grape with the thick skin. Its ratio of solids to juice is therefore high, and this accounts for its high tannin levels and deep color -- and for the fact that it is not always one of the nicest wines to drink young (Jancis Robinson's Wine Course, 2003). In Bordeaux, it is blended and calmed with other reds like merlot and cabernet franc; where it swirls proudly unblended, as in Napa or Australia, it can prompt even in the most sympathetic wine lovers (here, Robinson), epithets like "initially monstrous in their tannins" or "more like cold remedies in their youth."
What's the answer? Buy now, drink later. Or, snap up a California cab on your grocery store shelf whose vintage date says 2006 or 2005 or even earlier. They are not too difficult to find, since many people avoid Napa cabs because of their expense (they tend to start at $20 a bottle). If you want to drink it now, even that few years' aging will probably prove a help, and another year might make it even more enjoyable. Of course there is no lack of "jammy," "friendly," "fruit bomb" cabernets, vintage 2009 -- that they are becoming the norm horrifies experienced wine lovers -- but drinking them now may just confirm Jancis Robinson's observations, and make you wonder how well Robitussin pairs with a meal. Michael Broadbent's phrase "global red" also comes to mind. Recall that ideally we're looking, among all our noble grapes, for that elusive quality ...
Image from The Pursuit of Harpyness
P.s. Have we actually completed our survey of the noble grapes? We seem to have forgotten chenin blanc, upon whose nobility both Michael Broadbent and Karen MacNeil agree. And Broadbent adds muscat to his list, which is unusual to say the least.