DURING THE past few months manufacturers and distributors of cooking equipment have held three major exhibitions for their new products. The first two trade shows of the season were held in Atlanta and San Francisco and billed as "Gourmet Shows," restricting displayed products to gastronomic apparatus. The last, Chicago's 71st Annual Houseware Exhibition, contained everything from food processors and pots to hair dryers and burglar alarms.

Buyers from gigantic department stores and modest cooking equipment shops came from across the United States to evaluate, and in some cases purchase, the newest in cooking equipment and utensils.

As I visited the more than 2,000 booths, I kept hearing the same question . . . "What's new?" Cooking has become fashionable and as it is in every fashionable industry, each new season is expected to display a new style, a current direction, a fresh look. The new product madness that is so much a part of the clothing and automobile industries in our country was about to reach epidemic proportions in the cooking equipment business.

Fortunately, as stores across America are finding out, food preparation is only fashionable to a point and then function takes over. Most people have lost interest in whether or not this year's kitchen equipment color is avocado green or mojave mauve. What's become important is whether or not the tool does its job properly and how long it will last.

The major trend in cooking equipment over the past two years has been to professional quality construction and this tendency was much in evidence at all three shows. In pots and pans, the best professional lines shown were Legion, All Clad, Calphalon and General Housewares new Magnalite Professional. With each of these cookware products, the basic designs were developed to withstand a lifetime of professional use.

Farberware, Maxim and Cuisinart showed various styles of convection ovens. These tabletop, portable ovens cook faster and more evenly than conventional ovens by circulating the warm air completely around the food. This also eliminates the need for basting. Convection ovens have been used in professional kitchens for many years, and we will soon see an extensive advertising campaign by their manufacturers in order to introduce them to the home cook.

The Hobart Company has been a leading manufacturer of top quality professional kitchen equipment for many years. If you look into the work rooms of any good sized restaurant, you will see the big Hobart mixers, blenders, choppers and slicers. The Kitchen Aid division of Hobart produces the K5A and K45 countertop mixing machines originally designed for small restaurants but now used in over 2 million homes. Kitchen Aid has introduced a grain mill for the unit and Atlas Metal Spinning of south San Francisco, Calif., has produced a copper mixing bowl to fit the K5A and its whisk.

Simone Beck (co-author with Julia Child of "Mastering the Art of French Cooking") once gave me a spool of excellent linen kitchen twine. It was thin enough to fit through the head of my smallest trussing needle, strong enough to hold together under great heat and pressure and did not absorb fat. This same professional twine is now being made available in the United States by Rowoco in an attractive and functional dispenser. Rowoco also showed the Wear-Ever commercial pot holder, a rubber-like tube that slips over a pot handle and rejects heat up to 600 degrees Fahrenheit.

Krups, which is more or less the General Electric Company of Germany, showed its new and attractive electric pasta making machine. Bialetti o f Italy also introduced its own electric pasta maker. Both the Bialetti and Krups models are professional restaurant designs adapted for the home.

Salton, which always is prepared to electrify us in one way or another, has taken the convection oven technology and produced a convection toaster that reduces toasting time by 20 percent. Salton has also manufactured a home version of the high speed drink mixers found in luncheonettes. It is a close copy of the "malted milk machine" that stood on the counter of my Uncle Sam's candy store 30 years ago. It does a fine job on fruit and juice drinks and will hold up for the semiprofessional bartender.

By and large, the manufacturers and distributors who displayed their pro- ducts at this year's shows evidenced a high degree of skill and responsibility in the conception and design of their products. As the equipment talked about in this column and dozens of other new products and their advertisements reach our area this fall, you must ask yourself: "Do I really mince, chop and puree so much food that I need a food processor? Do I eat so much pasta that I need a home pasta machine? Will I ever grind my own flour on a regular basis"?

There is a tendency to think a particular piece of cooking equipment will change your entire gastronomic life, but in reality, that is rarely the case. If from time to time, you enjoy making fresh pastry dough, then the fact that a food processor can produce a pastry dough in 30 seconds will mean more and easier pastry making. But if pastry is a passing passion, it is unlikely the machine will be used for this function after the novelty wears off. Only consider the purchase of new cooking equipment in an area where you have had a long term interest.

Secondly, you must ask whether the equipment can really do what its manufacturers claim. I realize such analysis is difficult for the home cook, but common sense and some basic cooking knowledge can help. Look at what you're about to purchase. Carefully think about what you intend to use it for. If you see a machine marked professional ice crusher for the home, and it has a lovely pattern of flowers all around it, the blades are made of plastic and the motor sounds too weak to run a kid's Erector set, you should realize no professional would use it.

If you're really worried about the purchase and it's important to you, write to me, care of Cooks Catalogue, 1790 Broadway, New York, N.Y. 10019. Maybe I can help.