IT WOULD APPEAR to be a perfect wine for jolly old Saint Nick and other holiday celebrants.

Lower calories would mean replacing fewer buttons on that bulging red-and-white striped suit this season. And lower alcohol could mean safer sledding through busy holiday traffic.

"Light" wines are products that are 25 to 33 percent lower in calories and alcohol than regular wines and brought to you by certain wine producers who hope to cash in on the increasing popularity of "light" beer and diet soft drinks.

"It responds to the consumer's growing interest in light and low-calorie foods and beverages," says Michael Cliff of The Seagrams Wine Companies, whose vineyards have shipped 1 million cases of Light Chablis, Light Rose' and Light Rhine since August 1981.

Masson and three other large California producers are each spending millions of advertising dollars this year and next, not only to woo current wine drinkers who also happen to be health conscious, but also to attract newcomers.

While all of the companies currently marketing light wine share a common goal of increased sales in a stagnant wine market, they differ widely in market analysis, promotional emphasis and even production techniques. Indeed, all light wines are not created equally.

To make light wine, one generally must produce a wine with less alcohol. (Until the 1980 vintage, a California law dating from the post-Prohibition era prevented wineries in that state from selling wines below 10 percent alcohol because it was feared that wines at lower alcohol levels would quickly spoil.) Because alcohol is produced through the fermentation of natural sugar in grapes, the most common method of making light wine is by picking grapes at lower sugar levels (i.e., before fully ripened) so there is less sugar available to change into alcohol. Sebastiani Vineyards and Taylor California Cellars ferment their low-sugar grapes until all but a fraction of the sugar has been converted to alcohol, thus producing wines that are drier to the taste but finish somewhat thin. In addition, Beringer Vineyards chooses to stop fermentation before all of the natural sugar has been converted into alcohol. Thus, the residual sugar in their Los Hermanos Light Chablis produces a certain sweetness that renders the wine a bit fuller on the palate.

Masson and Almaden, the latest entrants in the light wine sweepstakes, have developed "secret" processes that vaporize a certain amount of alcohol after the wine is fermented to dryness from fully mature grapes.

These various production techniques yield wines that vary significantly in taste, alcoholic content and calories. These differences also reflect the fact that each company promotes its light wines differently, according to its view of the potential market. In this case at least, a rose' is not a rose'.

For example, not all producers stress only the low-calorie attributes of light wine. Beringer's Los Hermanos Light Chablis--among the first light wines to be released--emphasized its "smoother taste" when introduced in the spring of 1981. Although the wine is lower in alcohol (9 percent versus the usual 11 to 12 percent) and contains about one-fourth fewer calories (58 per 100 ml serving), Los Hermanos has only recently begun to mark its bottles with the added statement, "Fewer Calories Naturally." To the Beringer strategists, there is a market not just for dietetic wines but for wines that have a softer taste.

Sebastiani's "Light Country Wine" (9 percent alcohol, 57 calories per 100 ml) is cork-finished and aimed at drinkers looking for a wine lower in alcohol. When Sebastiani began advertising the low-alcohol virtues of its light wines, a federal agency halted its effort by invoking an archaic regulation that forbids advertisement of alcoholic content.

Undaunted, Sebastiani still believes that wines lower in alcohol will appeal to a segment of the market. "They are easier at lunch and increase the number of occasions at which wines can be drunk," says Billy Piersol, marketing director for the large, family-owned Sebastiani. "It is also being consumed," he says, "by older drinkers who appreciate lower alcohol in terms of taste and effect."

The promotion of light wines as low-calorie beverages began in earnest when Taylor California Cellars won a court fight last year with federal regulators over use of the term "light" in its advertising and labeling. Bottles of Taylor California Cellars' light wine expressly advertise "25 percent fewer calories." Its Light Chablis contains 53 calories (8.2 percent alcohol), while its Light Rose' and Light Rhine are only slightly higher in both calories and alcohol.

Motivated by brisk sales of diet sodas by its parent company (Coca Cola), Taylor California Cellars is targeting its light wine campaign for the health play. "Our lights are not positioned with taste as a factor," says vice president Margaret Stern in Atlanta. "There is no mystique about it. It is more a refreshment wine, easy-to-sip beverage." In her view, light wines are not even intended to complement food.

The low-cal drive intensified last fall, when Paul Masson introduced a Light Chablis with still fewer calories (50 and only 7.1 percent alcohol). Backed by the commitment of its parent (Seagrams) to "pour more money into TV and merchandising support for Masson Light than for any single product in Paul Masson's history," its Light Chablis and Light Rose' (54 calories and 7.1 percent alcohol) are now acknowledged to be out in front.

Almaden had initially been cool to the lights. "We had to make sure that the category was solid," says Greg Sivaslian, director of marketing for Almaden. "So we hung back somewhat, then we decided to move on it," adds Almaden's top marketing official in San Jose. Sivaslian notes that Almaden's Light Chablis has fewer calories than even Masson (47) and is currently the lowest in alcohol at 7 percent, the minimum level permitted by federal law.

While firms such as Geyser Peak, Delicato, Franzia and San Martin also have introduced light or "soft" wines, there is some doubt in the industry that the category is viable. California pioneer Robert Mondavi--whose winery now sells a million cases a year nationwide--is unconvinced that light wines will deliver enough taste or fullness to establish the 10 to 15 percent submarket that others are predicting. Neither Gallo--the largest California wine producer--nor Inglenook (United Vintners) has expressed interest in offering such wines.

"The jury is still out," says Sebastiani's Billy Piersol, who notes that 1983 will be the first full year that many large producers will be marketing a range of light wines. He states that expectations for the new category have not been met, but he also notes that wine sales generally have leveled off in 1982.

Masson and Taylor's California Cellars--the light leaders--are reportedly pleased with current sales and plan to increase their promotion of light wines through 1983. Some industry sources, however, say the leaders' light wine sales have resulted in reduced sales for those companies' regular Chablis and other generic wines.

"We see the category as definitely being there," says Taylor California Cellars' Stern. She notes that the public's response to light beer and diet sodas was not immediate. Other industry spokesmen agree. "The light beer category took years to develop," says Sivaslian, who believes that Almaden's light wines will have particular appeal to calorie-conscious women. Piersol at Sabastiani recalls that the reaction to diet sodas was terrible. "They really haven't changed," she says, "the public has just gotten used to the different taste."

But the incentive for compromising taste in soft drinks is often a reduction from more than 100 calories per serving to as little as one calorie. Such reductions are not possible with wine. Moreover, wine is not a high-calorie beverage to begin with and the need for a lower calorie substitute is not as compelling as in the instance of beer. In addition, because wine is perceived more as a beverage to accompany and enhance food, it may prove difficult to persuade wine drinkers to accept a watered-down product.

So far, at least, it does not appear that light wine is significantly expanding the base of wine consumers. While frontrunners such as Masson and Taylor California Cellars hope to attract new entry-level wine drinkers through extensive advertising and retail promotion, the payoff may be years away--if ever.

"In beer, the lights brought in the women," says Sivaslian. "We are looking at the 33 percent of Americans that are potential wine drinkers," he says. "Getting new consumers through light wines--that could be an important prospect for expanding our base."

"It's not happening," cautions Piersol. "Light wine is not going to lead the way." He even suggests that Sebastiani may be close to giving up the effort.

Whether it is the wine industry's Edsel or a timely answer for health-conscious consumers, light wine clearly offers an alternative. Slightly fruity on the nose, often marred by chemical-like aromas, the light wines certainly are thinner in body, paler in color and finish somewhat short. They do, however, contain noticeably less alcohol (although this may present longevity problems for bottles that remain too long on retailers shelves).

If the calorie-laden Christmas season stimulates you to try a bottle (most come in 1.5 liter sizes), do not expect a complex or memorable experience. Light is less and soft usually means slightly sweet.

And if it turns out that the lights are not your bag, there is always the option of leaving them for the large one carried by that bearded fellow on Christmas Eve. It may prove more rewarding than cookies and milk.