People used to be proud of their cooking. Now they boast of their shopping. Knowing where to buy wild strawberries draws more envy than baking the best biscuits for the shortcake they'll serve.

Mass marketing has done that to us. It has routinized our eating options. If you want apples, you're stuck with buying golden delicious apples. That's the trouble. And the problem is international; three-quarters of the world's apple trade is the bland golden delicious, estimated Jane Grigson, and she's on an eternal campaign against blandness.

Grigson, who has written nearly two dozen cookbooks from her farm in Wiltshire, England, and the cave where she spends her summers in France, was railing about such things at a recent meeting of the American Institute of Wine and Food at the Watergate in Washington. The guests were nibbling Welsh rarebit and English farm cheeses, washing them down with such rarely seen English beers as Samuel Smith's Old Brewery Pale Ale and Porter and Ridley's Ale. These deep-colored complex-tasting brews made the point; they were anything but bland.

"I used to think salvation lay in cooking," confessed Grigson, a big, soft, grandmotherly woman with a twinkly look and a halo of gray hair. Lately she has been converted: "Salvation lies in shopping," she now preaches. She campaigns against tasteless stuff that doesn't offend anybody: "But if it doesn't offend anybody it's not going to delight anybody either."

Grigson herself is a prime example of being willing to offend in order to delight. Anybody who has read Grigson's books, the latest being "Jane Grigson's Fruit Book" (Atheneum, 1982), "Jane Grigson's Book of European Cookery" (Atheneum, 1983), "Jane Grigson's British Cookery" (Atheneum, 1985) and her columns in The Observer Sunday Magazine, knows her as a particularly literate and witty writer. Anybody who has heard her talk knows she has perfected the art of subtle devastation. Someone from the audience spoke out in contradiction of Grigson, and she just cracked the tiniest smile and answered something to the effect of, "Oh, really?" The audience chuckled; the questioner couldn't even find his wounds.

On assignment from The Observer to write about English regional cooking, Grigson found that the path to it was through shopping. The pork pie maker, the mustard maker, the cheesemaker and the oatmeal maker were what made one region distinct from another in such a small country well-connected by mass media. So she set out to find small manufacturers -- food craftspeople, actually -- who produced reliably excellent foods. The key was to find those people who went into such businesses because there was no product they considered good enough to eat. And the question to ask was whether they ate what they produced. If it was good enough for them, it was good enough for fastidious chefs, who became the financial supporters of these products. "I began to see the networks of dependency," said Grigson, and the project began to turn into a book -- "British Cookery." The book turned into a campaign by Grigson to support and promote such producers. Grigson thinks of it as a culinary version of England's Rare Breed Survival Trust, which acts to save rare breeds from extinction.

As part of her campaign, Grigson rails against shoddily made hams. According to her description, they take perfectly good pork legs and tip them "into a sort of tumbler dryer" with water, and they squeeze the legs together again, she said. "It's a bit like the judgment day, except that you don't get your own leg."

She tells some stories with happy endings: A small sausage maker, after getting some publicity, received 7,000 orders. It would take her six months to fill those orders, she warned each of the callers. They didn't cancel, they responded instead with, "Since we haven't bought a sausage in 10 years, we can wait another six months for yours."

The major success story in Britain's small production is cheese. Patrick Rance, a retired military man who wears a monocle but no socks and whom Grigson calls "a wild-eyed cheese fanatic," produced a book describing British cheeses by region and listing every good producer. It became the bible of the cheese revivalists. And the recognition allowed minuscule producers to survive.

Another factor improving the lot of small food producers in England is overnight mail, which allows them to sell from their home base to all over the country.

Grigson, however, is "stuck in the middle of the country," which means she has little access to good food. When she entertains, she likes to show off the best of British ingredients. So she has to operate with a pretty narrow repertoire. She has lightened the old Yorkshire Pudding, which she says used to be "a fairly mattressy sort of thing." And she can manage to order good oysters and salmon. She can also find fresh sorrel and berries. So she starts with sorrel soup, which is simply potato and onion soup put in the blender with raw sorrel at the last minute so the sorrel barely cooks and still tastes fresh. For dessert the berries will go into a cre me brule'e. She will end with cheeses and accompany the meal with English white wine.

The idea of serving English wine brought gasps from Grigson's audience. So she elaborated that when she serves it, "I keep my hand over the label and see what they say." Grigson's home town does provide good bread, but to find good butter, she cautioned, you have to be in a city. That, too, brought a surprised reaction.

Which led into her conclusion. "It's safe to say," confided Grigson, "that whenever you hear an attractive legend about food, it's wrong." Tabletalk

So much for healthy. A study by MRCA Information Services of the menus of 4,000 adults revealed that dieters ate 30 percent more muffins, 46 percent more chocolate bars and twice as many croissants in 1984 as did dieters in a similar study two years earlier. What's the secret of a great chef's success? Some people must think it is in the pots and pans, because coming on the market is Paul Bocuse cookware. JANE GRIGSON'S SORREL SOUP (Makes 1 quart)

1 cup chopped onions

2 tablespoons butter

3/4 pound boiling potatoes

3 cups chicken broth

1/4 pound or 1 bunch sorrel leaves

Lemon juice to taste

Salt and freshly ground pepper

1/4 to 1/2 cup whipping cream

In a large saucepan, saute' onions in butter until soft, about 15 minutes. Chop potatoes coarsely and add to onions, along with chicken broth. Cook until potatoes are tender, about 20 minutes. Wash sorrel, remove any coarse ribs, and shred the leaves. Combine soup and sorrel in a blender, adding only a quarter of each at a time so the hot soup doesn't overflow. Return all the soup to the saucepan and reheat. Taste for seasoning, adding lemon juice, salt and pepper to taste. Stir in cream to taste. Serve either very hot or chilled.