THE AVERAGE consumer spends 15 to 20 minutes shopping in a large supermarket selecting from as many as 10,00 products and is subject to any number of marketing techniques to entice her to buy more, said Karen Owens a registered dietitian, nutrition educator and consultant to the food industry.

If shoppers are aware of supermarket psychology they can join the game rather than be victimized by it. And, Owens says, they might save themselves money by controlling impulse purchases. Both food companies and retailers use techniques such as these:

A product label is designed to catch the customer's attention. "Look at a box of Tide and see the colored rings on the package -- they draw you in," Owens said. When Pillsbury, a company Owens represents, introduced a snack food called Wheat Nuts, they chose a distinctive red label because most other nut snacks the Wheat Nuts would compete with have blue labels. Thus it would stand out on the shelves.

Have you ever noticed music in a supermarket? "It's music to consume by. It's recognizable, a little peppy, music to hum to," she said.

The placement of foods can make a difference too. In most stores milk, a frequently purchased product, is at the back of the store, she said. To get there a shopper has to pass a lot of shelves.

Research has shown that if a shopper has to backtrack to pick up an item in his or her list, he is likely to buy one extra item, too. Some stores change the location of high selling products so the customer has to seek them out. In the California store where Owens shops, garlic spread is one product that is moved around. It might be with the seasoning, next to french bread, or near the pasta products. Other examples of big sellers that could be moved about are marshmallows (they may be with the baking supplies, candies, snacks, or beverages) and mineral water (with milk or juices, soft drinks or liquor).

The average shopper Owens refers to is a 5-foot-4 inch woman, and when a supermarket wants to move a product quickly, it is placed at the easiest level for that size woman to reach -- Owens demonstrated by bringing her arms up to shoulder level in a standing position. The type of products that might be on shelves at that level are high priced items, store brands, or promotional items, she said, products the retailer wants to move in volume.

"It pays to stoop, look up and reach for a product," she added.

Products that might appeal to small children are shelved so a child riding in the grocery cart can reach out of the cart and get their hands on them. At the cash register a customer also is tempted by such impulse items as magazines, gum for the kids, and a big bag of toothbrushes, or a similar last minute purchase.

Tempting aromas coming from deli counters also attract customers. "All the senses are involved," she said. "If you're aware of the aromas, say to yourself "that smells good, but . . ." On-premises bakeries are equally enticing.

When Owens worked for a West Coast supermarket, it looked like a bad year for turkey. Prices were up and the supermarket already was committed to an earlier purchase. To sell them Thanksgiving week, a turkey was roasted in each of the stores several days before the holiday. The postscript to the story is that all the turkeys were sold, even at the higher price.

Armed with this information, Owens offered her own game plan for shopping:

Always shop with a list. Shopper studies have shown that a woman who goes to the store for three items without a list actually buys as many as 8 to 11 products. A man under the same circumstances buys as many as 20 item.

Leave husband and kids at home.

Don't shop when you're hungry. Again, studies have shown that can add $10 to a grocery bill.

Enter the door, pick up the cart, and go up and down every single aisle to avoid backtracking and those impulse purchases.

Mark approximate prices on shopping list and look at prices as you pick up products. This listing then can be referred to at the checkout counter. Reach to the back of shelves or racks to see if there is older and less expensive stock. Also check price per ounce and per serving. Owens noted that many packaging materials such as plastic handles, color inks, cardboard and cellophane are oil-based and expensive. With products such as detergents she especially checks price per ounce.