QUESTION- What are capers?

ANSWER- They are unopened flower buds from a trailing shrub called Capparis spinosa, which has been around since ancient times. They are known to have been introduced into France by the Greeks about 600 B.C., and the Romans apparently had capers as far back as written records extend.The reason that they are relatively expensive is that capers must be harvested every couple of days to get the buds at their earliest edible stage. Price aside, capers do impart an excellent flavor to both hot and cold foods. They can enhance a mayonnaise for salmon or tuna salad, or add an interesting twist to a standard vinaigrette. They are an ingredient in some pasta sauces, and can be used along with other herbs or spices to season steamed vegetables.

One of our favorite low-fat dinners, which is enhanced by capers, is a quickly prepared dish in which shallots are first sauteed in a little olive oil. Then chunks of white meat chicken are rapidly sauteed, season with fresh ground pepper, a heaping spoonful of Dijon mustard, and a sprinkling of capers. The pan is then deglazed with a little red wine.

Accompanied by steamed rice, the whole dish, elegant enough for company, can be ready for the table in about 20 minutes.

QUESTION - I'm interested in learning how to use the behavior modification approach to weight reduction. Can you recommend a book to instruct me?

ANSWER - Get hold of the newly revised edition of "Habits Not Diets: The Secret to Lifetime Weight Control" by James Ferguson, M.D. (Bull Publishing, $12.95). This is an update of an excellent volume first published in 1976. In a 21-week program that focuses on both eating and exercise, Dr. Ferguson reflects a clear understanding of the obstacles blocking the path of weight-loss attempts. In an honest and candid manner, he provides sensible guidelines for achieving success.

A different topic is introduced each week, but new information is integrated with earlier instructions to reinforce positive behavioral changes and prevent relapses. Self-checks and reasonable "homework" assignments help keep the dieter on track. And the program addresses the all-important issue of maintenance. We think the program is well worth a try.

QUESTION - I recently had stewed gooseberries for the first time and liked them a lot. What's the story on them nutritionally?

ANSWER - A half-cup of raw gooseberries has under 35 calories. It also contains some vitamin C, as well as small amounts of B vitamins. But they are generally not served raw. We are far more likely to encounter them stewed or used in fruit tarts, sauces or jams. Naturally, all of these forms of preparation add calories. And, to varying degrees, they destroy the vitamin C that was present in the fresh fruit.

Gooseberries are quite popular in other countries, especially England and Scotland, where they are used in numerous ways in main dishes-in sauces for fish or veal, stuffing for goose, in tarts, puddings and other desserts, and in jams and jellies. While we tend to think of the green fruit that is generally cooked, there are also white, yellow and red gooseberries which can be eaten fresh.

As you might expect, the word gooseberry has nothing to do with goose. It apparently is a garbling of a variety of names linked to the French groseille, or red currant.