Since the late 1990s, the book of sauvignon blanc has had an added chapter, one that has changed the entire face of the grape and altered how wine lovers view it.

Before then, there were essentially three different versions of the grape. The classic was from the eastern Loire Valley in France, where Sancerre and Pouilly-Fum?offered a minerally, grapefruity sort of aroma and austere taste that was superb with lean and delicate seafood. And the wines aged well.

From Bordeaux, white wines blended with both sauvignon blanc and semillon were often aged in barrels. The wines were richer and also did well with bottle age.

California's best SBs were drinkable on release and were more tropical, less distinctively varietal and were charmingly simple.

Into this picture came an upstart from a country that, as recently as 1973, didn't even have sauvignon blanc planted. New Zealand offered a unique style of the wine, with scents of gooseberry, grass, green herbs, and an exotic nature never before seen with this grape.

After a fitful start, during which we heard reactions like "love or hate" and "you won't believe this," the public soon became fascinated with these wines. Today the wine is so widely accepted that it's sold everywhere, and it is even referred to with four initials: NZ SB.

So the next question is: Will the broad market accept New Zealand's next wave of drama with the same enthusiasm?

That scenario is unlikely since the wines are red, they are usually seen as a bit leaner than the voluptuous style more common in the United States, and neither of these wines is in vogue with most wine consumers these days.

The wines are merlot and syrah, and during a recent trip to New Zealand I tasted two dozen wines from these two grapes and found many exceptional examples, and most quite reasonably priced.

The main reason that neither of these two terrific wines is likely to find a ready market here is that at their best the wines are a) somewhat exotic with good natural acidities, and b) assertively varietal in aroma to be true to the grapes from which they came.

Why these two factors may make the wines less well accepted here is hard to explain, but part of the reason has nothing to do with New Zealand. It has to do with the fact that both grapes are under attack in many quarters in this country.

Merlot has been so disliked in this country that a character in the movie "Sideways" took to viciously slamming the wine. And most winemakers who have syrah to sell face one of the most difficult tasks of all: consumers who are bored with the variety's sameness.

New Zealand merlot, however, generally smells and tastes like true merlot, with cherries, hints of dried herbs like thyme, olive, and green tea along with fruity-berry smells. And NZ Merlot is usually made dry, so it works well with food.

Syrah, also made to work with rustic foods, is usually scented with wild and exotic aromas such as pepper (white or black), sandalwood, violets and dried Near East spices.

One thing that will make New Zealand reds a bit dicey to catch on with Americans may well be the reluctance of some Kiwi producers to send wines here. To be sure, some of the most appealing red wines from New Zealand here now are pinot noirs, the most exciting from Central Otago, but also from Martinborough and Marlborough.

The syrahs and merlots I tasted from the Hawkes Bay region are a bit slow to arrive here, and those few that are here now are exciting.

<b>Wine of the week:</b> 2012 Mission Estate Syrah, Martinborough ($15) — This lighter styled red wine was not aged in oak, and offers distinctive pepper and violet aromas and good acidity for matching with lighter meat dishes as well as rich cheeses. Excellent value.

<i>Sonoma County resident Dan Berger publishes "Vintage Experiences," a weekly wine newsletter. Write to him at winenut@gmail.com.</i>