Mental munchings for a lazy summer Sunday: Our favorite quotation for the month of July comes from Yale professor Judith Rodin, who says that dieting is the chief cause of obesity in America. We're convinced, and are thinking of demonstrating our understanding at brunch with double hollandaise on our eggs benedict.

Our favorite news lead of the season came from Chicago restaurateur and food writer Louis Szathmary, whose instruction to a mushroom recipe read, "Group sex was unknown during my youth in Transylvania."

If you are looking for art to go with your color scheme and your family is the messy sort, consider the exhibit by Elyse Weissberg coming to the Deran Building in Arlington in August. The painting that intrigued us was described as a mixed media work in "oil, crayon and food (coffee, pea soup) mixed with paint."

That reminds us of our long-held wonderment over the woman who discovered that the best way to remove chewing gum from her children's hair was with peanut butter. We have whiled away hours imagining what she must have tried before she got around to peanut butter.

News traveling on the heat waves: To many shoppers, seedless green grapes are for eating and red grapes, with their pesky seeds, are for decoration. Naturally (or unnaturally), someone has thus managed to produce a seedless red grape. Red flame seedless, it is called, hybrid of the cardinal, thompson seedless, red malaga, tifafihi ahmer and muscat of Alexandria. Impressive lineage. And short supply. Now if someone would only come up with a peeled grape . . .

Also from the summer news beat: Dixie cups aren't what they used to be. They're better. Now they are filled with Bassetts ice cream. Pawn the chocolate off on the kids. Save the Irish coffee for yourself.

If you wonder where your next ice cream is coming from, it may be from potatoes. German scientists, probably having had their fill of potato pancakes and potato dumplings, have invented a new use for them, as a low-calorie fat and sugar extender in ice cream. The low calorie count of this potato product, called SHP gel, comes from its being 75 per cent water.

Celebration is a warm Thai spring roll. Or curry, or marinated chicken, or fried fish cakes. And the cause for celebration today is the beginning of the Budhist Lent. The place is the Wat Thai Temple, 9033 Georgia Ave., Silver Spring, its food and gift bazaar opening at 3:30 p.m. Dancing start at 4 p.m., and the food sales continue as long as the food lasts. For more information, call 585-5215.

While Americans watch reruns of "M*A*S*H" reruns, French television viewers get such first-time-ever events as the construction of the world's highest pyramid of champagne glasses. It used 1,365 crystal glasses (valued at $40 each), but Moet and Chandon, whose public relations director constructed it, balked -- not at the expense, but at the time -- when it was estimated that filling the glasses would have required opening 200 bottles of bubbly. They settled for a single bottle, a 12-liter salmanazar, to cascade from the top glass.

Communication is the big food industry trend this year. The Food Marketing Institute convention in Dallas last May showed talking cash registers, which call out the price as an item is electronically scanned. And at Chicago's annual National Restaurant Association convention, robots stole the show. They roamed through the crowds, shaking people's hands, complimenting people and asking them questions. What the crowd didn't notice were the men with hand microphones nearby controlling the robots. Next we may have electronic cashiers and robot shoppers.

Further reports from the restaurant show revealed no major changes in kitchen equipment, merely refinements: computerized ovens, low-energy appliances such as toasters, and a machine that purees 10 gallons of soup at a time. (Look for lots of cream of zucchini on menus of the future).