New Delhi, July 24 -- Ken Silver knows beef because he knows Philly cheesesteak. He hopes that a summer spike in how much he pays for his restaurant's main product doesn't cause heartburn for him or his customers.

Silver, president of Jim's South St. in Philadelphia, said he might have to raise prices for his popular sandwiches to offset the rising cost of beef or even declare a market price, which is commonly associated with seafood.

"I really hate to do that," said Silver, whose father started the business in 1976.

U.S. beef prices have been steadily rising over the past 20 years because the supply of cattle remains tight while beef remains popular.

Silver said the price of beef from his supplier now is about $1 more per pound than ...