Not since the Gaslight Club's Christmas in July party has there been an event as out of context as the Beach Boy's Thanksgiving Dinner. It was prepared and served to them backstage on the Washington Monument grounds July 4. According to Howard Solganik of the Georgetown Wine and Food Company, which caters to food whims of rock stars, 22 persons sat at picnic tables in mid-afternoon and dug into freshly roasted turkey served with cranberry sauce, potatoes and green beans. Actually, all but one ate turkey. Beach Boy Mike Love is a vegetarian. He ate vegtable lasagna. The group drank Perrier and beer and had strawberries for dessert.

What will they think of for Thanksgiving?

Much to her surprise, the defending champion held her crown at the annual Bastille Day culinary arts competition sponsored by L'Academie de Cuisine in Bethesda. Joan Burka's truffled mousse de foie gras was judged best in show by a panel of three professional chefs. For the effort she won a trip to Paris. Second prize went to Leslie Bloom, who created a scallop terrine with salmon mousse. The thrid-prize winner was Nichole O'Neill.

Her entry was a medley of dessert charlottes. There were 39 entries and more than 250 persons came to the Academie to see them displayed.

Arthur DeCuir, chef, restaurateur and consultant, was in town recently with the mission of convincing more people to cook with -- and presumably drink -- Champale. He uses it in place of wine in recipies. It has less alcohol than wine and costs less, he explained.

Looking at the restaurant scene, DeCuir, a Louisiana native, sees a return to formal dining on one hand and, on the other, a fad for Western food and clothing. He is working with Sardi's in New York City's theater district, helping to add "fancy food items" to the menu and retraining the service staff for tableside preparation of such items as Caesar salads and carving of dishes like rack of lamb. "With prices where they are now," he said, "people want more than a waiter coming by to drop your food on the table and then coming back to collect the check."

Western will be the next craze, he predicted, and talked of doing a barbecue restaurant, "but to do it right. You can't just cook the meat in an oven," he said.

"You have to smoke it for 12 to 14 hours. City people will like it, but you can't get fancy or charge fantastic prices." Another temptation is to mount a "great Creole restaurant" in New York, using products imported from Louisiana.

DeCuir feels the restaurant business has expanded to the point where black chefs have wider opportunities to move around to learn the new styles and techniques they need to command top restaurant or hotel ktichens or move into management.

A husband-and-wife team is providing some of New York City's best-known restaurants with a splendid version of smoked trout and very creditable smoked salmon. Peter Heinman, a marine biologist, began experimenting on a home-smoker in Mt. Kisco, N.Y. He soon built his own, devised a special brine and cooked the fish over hickory chips. His wife, Karen, took on the chore of marketing the products under the name "Homarus" and quickly gained a foothold in New York. The Heinman's handle New York deliveries themselves. Turner Fisheries of Boston ships the fish to other cities. The fish they buy comes from all directions: Pacific salmon, Australian eel, Idaho trout and Atlantic sturgeon, to cite a few. Homarus products are now in several local restaurants and may be purchased at Waghal's and the Georgetown Wine and Food Company.

Fans of Shellfish Digest, that remarkabl combination of scholarship and culinary lore, should know that the summer issue, volume 3, number 4, contains 32 pages plus a supplement called the Shellfish Shopper. The cover contains a lovely print of crab fishing off the Fife coast of Scotland in the 19th century. Inside there is information on barbecuing shellfish, cleaning squid and other subjects. But the magazine defies synopsis. Spend $5 for a subscription (a year's worth -- four issues, more or less) and sort it out for yourself. The address is P.O. Box 469, Georgetown, Del. 19947.

Dedicated cookbook collectors should know of a mail-order service called Just Cookbooks! The owner, Wendy Miller Schulenburg, features American regional and community books, international, ethnic and a category called "not quite-cookbooks," food books without recipes. Her catalogue is available for $1, which will be refunded from the first order. The address is P.O. Box 192-F, Palatine, Ill. 60067. An even more imposing catalogue is The Wine and Food Library of Jan Longone of Ann Arbor, Mich. The sixth edition, 30 pages worth, is available for $2 from Mrs. Longone at 1207 W. Madison, Ann Arbor, Mich. 48103.