Nutrition hotline: this issue's Nutrition Hotline introduces readers to tempeh and to some great ways to incorporate it into a meal.

QUESTION: "I've heard tempeh is a good protein source for vegetarians, but I don't know anything about it. What is it, and where can I buy it? Most importantly, how is it used?"

ANSWER: Most people have heard of tofu, that block of white soybean curd served in Buddhas Delight at most Chinese restaurants. But tempeh is an equally versatile and, I'd argue, tastier and more practical soyfood with a firmer texture. It's a great staple to keep on hand at home.

Tempeh is easy to use. Like tofu, it picks up the flavors of the foods with which it's cooked. Use tempeh to make chili, soups, stews, sauces, and casseroles. It can also be grilled and served as an entree or used as an ingredient for sandwich and burrito fillings.

But tempeh, a traditional Indonesian soyfood, has one big nutritional advantage over tofu: It's a whole food. In contrast with tofu, which is made with soymilk, tempeh is made with whole soybeans, making it a good source of fiber. It's a rich source of protein and a good source of riboflavin, thiamin, niacin, calcium, iron, and zinc. In addition, tempeh is low in saturated fat, cholesterol-free, and full of beneficial phytochemicals.

To make tempeh, whole soybeans are mixed with a grain--often rice--and a mold culture. The mixture is fermented and pressed into a firm, flat, rectangular block. The finished product comes in different colors and flavors, depending upon the ingredients used to make it.

WHERE CAN YOU FIND TEMPEH?

Some supermarkets carry tempeh, but you're most likely to find it in the refrigerated and frozen foods sections of natural foods stores. It's usually sold in 8-ounce vacuum-packed plastic packages.

Tempeh keeps for approximately one week in the refrigerator and for several months in the freezer. I usually buy several packages at a time and keep them in the freezer until needed. Thaw tempeh in the refrigerator overnight or in a microwave oven in a couple of minutes. For food safety reasons, tempeh should not be left at room temperature for more than two hours.

HOW CAN YOU USE TEMPEH?

Here are some of my favorite ways to cook with tempeh:

* As a sandwich filling. Use tempeh crumbled in mock chicken salad or in place of beef in recipes for Sloppy Joes. Strips can be barbequed or grilled and served in tempeh, lettuce, and tomato sandwiches on toasted whole grain bread.

* Eat it in burritos, tacos, and fajitas. Cut tempeh into strips and grill it before you add it to your favorite Mexican dishes.

* Use grilled or marinated chunks of tempeh and vegetables in shish kabobs served with rice pilaf and pita pockets.

* Pan-fry cubes of tempeh in soy-ginger sauce and serve it over a plate of cooked greens and steamed rice.

Tempeh is made with whole soybeans, so its texture is firm. To soften it and make it easier to crumble into recipes for sauces, chili, and casseroles, steam the tempeh for a few minutes in a steamer basket or over a pot of boiling water. Be sure to let it cool before handling. Tempeh used in recipes that call for slabs or strips usually doesn't require any special preparation first.

For an introduction to cooking with tempeh, try The Tempeh Cookbook by Dorothy Bates (The Book Publishing Company, 1989). It's a skinny paperback classic with some color photographs and simple recipes. Most bookstores will order it for you, or you can order it by sending $17 (includes postage and handling) to The VRG, EO. Box 1463, Baltimore, MD 21203. You may also order this book with a major credit card by calling [phone] Monday through Friday from 9 a.m. to 5 p.m. Eastern Time.

Tempeh may be new to you, but give it a try. It's one more healthy and good-tasting option when you're wondering what's for dinner.