(FORTUNE Small Business) – Many red wines today taste a little like Black Forest cake in a glass: dense, with gobs of fruit, a splash of black cherry, and a twist of vanilla. For that you can thank (or blame) Robert M. Parker Jr., the famous wine critic and publisher of The Wine Advocate. Parker is the most influential wine taster in the world--a high rating from him can send prices soaring. Because he has so much clout, winemakers line up to create reds with the intense fruitiness Parker prefers. (For whites, he likes bold flavors too.)

There's even a wine-consulting company in Sonoma, Calif., called Enologix that says it can boost a wine's Parker ratings. President Leo McCloskey says his company uses "Old World, noninterventionist techniques," though he also maintains a database of the chemical components in wine, and he uses science to help winemakers predict the peak harvest time for better scores.

After the grapes have been picked and pressed, winemakers have other technological tricks they can use to make the wines Parker-pleasing. Some add designer yeasts that can impart a specific flavor, like cherry extract. If a wine tastes too harsh, a process called micro-oxygenation--in which bubbles are blown through the wine--can smooth out the tannins and eliminate off odors. If it's not tannic enough, powdered tannins can be mixed in.

Even more lab-intensive is reverse osmosis, an industrial technique used to separate wine into clear liquid (mostly water and alcohol) and sludge. The winemaker can then reconstruct the wine, bringing down alcohol levels and concentrating flavors. Vinovation, a Sebastopol, Calif., company, provides that service as part of its Wine Quality Enhancement program. Co-founder Clark Smith declines to name specific clients, though he says he has worked with about half the wineries in California.

None of this fiddling is illegal, but many wine purists consider it a form of cheating. And some brave winemakers are going against the trend and taking their chances with the soil they've chosen and the weather each season gives them. Organic vintner Richard Figiel, 57, runs the Silver Thread winery, a one-man operation in the Finger Lakes region of New York State (which is mostly ignored by Parker). Figiel uses an old-fashioned press and makes delicious pinot noir, chardonnay, and riesling, all for less than $22 a bottle. His 2002 riesling was sweeter than he wanted (he's still not sure why--possibly a cold cellar that made the yeast less effective). While he could have corrected that in the laboratory, he didn't. "That's what nature wanted to do," he says.

Other wineries with tasty, distinctive products are, in California, Au Bon Climat (pinot noir and chardonnay), Copain Wine Cellars (pinot noir and syrah), and Newton Vineyard (especially the 2000 Epic merlot, $42 a bottle). In Oregon there's Brick House (pinot noir), and in Washington, Owens-Sullivan (brilliant cabernet franc).

Steve Edmunds, 56, who with his wife owns Edmunds St. John in Berkeley, is yet another example. Entirely self-taught, Edmunds says he has occasionally resorted to science in his 20-year career, but "only when it was clear that I'd lose the wine if I didn't, and not to create a particular effect." His syrah has a cult following, particularly a Rhône-style blend called Rocks and Gravel ($22) and a cold-weather wine called Bassetti Vineyard syrah ($40). Even without relying on technology, Edmunds produces wines that get great Parker ratings, often in the low 90s (though he has sunk as low as 76). As he explains on his website, "I've deliberately chosen not to court the market, i.e., the commercial context out of which so much modern wine is being formulated. I don't always get it right, but what I do is done honestly."