GLENDALE, CALIF., JAN. 1 -- Grocery shopping would probably fail to show up on a typical teenager's Top 10 List of Things to Do. But for a young Tim Crull, shopping for food was something to look forward to.

"As a teenager, I used to love to go to supermarkets. I'd go shopping for my mother. I still go to the stores ... looking for what's new. To me it's part of the game," Crull said.

These days, the 59-year-old president of Carnation Co. is a player in one of the toughest games around: the $475 billion U.S. food industry.

Crull today became an even more formidable opponent as he took charge of the far-flung companies -- including Carnation, Stouffer Foods Corp. and Hills Bros. Coffee Inc. -- that make up the U.S. holdings of Swiss foods giant Nestle SA.

Nestle, by combining its U.S. subsidiaries under one corporate umbrella, hopes to create a company large and diverse enough to survive in the food industry big leagues during the 1990s.

While the consolidation may be a long and complicated process that could result in layoffs, industry analysts say the move will help Nestle regain lost ground in some key businesses and remain competitive in the tougher times that lie ahead.

Despite more than $6 billion in annual sales, Nestle USA is dwarfed by giants such as ConAgra Inc., with 1989 sales of $15.5 billion, and Phillip Morris Inc.'s Kraft General Foods Group subsidiary, the nation's largest food firm, with more than $22 billion in revenue during 1989.

"Nestle is starting to realize that results have been somewhat sluggish in the U.S.," said food industry analyst Nomi Ghez at Goldman Sachs & Co. "They have not been taking full advantage of their size.

"Reality is forcing them to look at these opportunities more aggressively. They have very strong brands in the U.S., but in the last two or three years they have been losing market share in very important categories," Ghez said.

Some of the lost ground has come in the frozen food area, where Stouffer's Lean Cuisine products have been battling inroads made by ConAgra's Healthy Choice line.

In the coffee business, Nestle's Hills Bros. division contends with an increasingly aggressive Kraft General Foods.

The Friskies pet food division has come under severe competitive pressures lately, analysts say. Carnation's foray into the infant formula business has also fizzled, and the company, over the objections of pediatricians and advocates of breast feeding, will begin advertising its Good Start formula directly to mothers beginning this month.

Furthermore, Nestle, like other food companies, must cope with a recession after the boom years of the last decade.

"The '80s were a very awesome time for the food industry," said Ronald B. Morrow, a food and tobacco industry analyst at Smith Barney, Harris Upham & Co. "In the '90s, costs are increasing. Some areas {such as cereals} are slowing down. It will not be as robust as the '80s."

Tim F. Crull, an easygoing man who joined Carnation in 1955, knows of the challenges and is preparing Nestle USA and its employees for them. The move toward a more aggressive, fast-lane approach is reflected at Carnation's new, postmodern headquarters in Glendale, eight miles north of Los Angeles, where employees are still trying to figure out the meaning of avant-garde works created by California artists. That's a big departure from the prints of Carnation ads that decorated the walls of the company's former Los Angeles home.

"It's a statement of what our company is and wants to be," Crull said of the company's bold new tower and works of art. "The art here is to give our employees a creative environment to work in."

As chief executive officer of Nestle USA, Crull will oversee the single largest national market for Nestle, which had worldwide sales of nearly $31 billion in 1989. While Crull minds the food business, Chairman James M. Biggar will tend to the Wine World division and Stouffer Hotels & Resorts.

Nestle's much-applauded consolidation efforts have already begun. Last June, it consolidated all its food service divisions at the Glendale office. It is now in the process of merging the distribution networks.

"Nestle has many sales forces in the United States," Crull said. "Do we need seven sales forces or can we do it better with two or three? These will be things we will review."

So far, no employee has lost a job as a result of the consolidation, but Crull says he cannot guarantee jobs in the long run. "We don't really know" if people will be laid off, he said.

The advantages of Nestle's efforts outweigh any short-term difficulties, analysts say. Kraft and General Foods, for example, were able to cut costs by $300 million to $400 million the first year after their merger. A larger, consolidated operation "also gives you more muscle with the {retail} trade and better chance to get shelf space," said Ghez.

Crull said he is eager to begin reaping the benefits of consolidation. "By putting them together, we will have a lot of synergies that will make us a lower-cost producer. It will also give us more advertising dollars that will make us more competitive with the Procter & Gamble and the Kraft General Foods companies."