The booming ethanol industry has caused the price of corn to double since this time last year to $3.66 a bushel, despite an abundant harvest, and is inching toward the rarely breached $4-a-bushel mark.

Big food companies like Tyson Foods Inc., the giant chicken processor, and ketchup maker H.J. Heinz Co. are feeling the pinch. Bottlers of Coca-Cola Co. and PepsiCo Inc. are raising prices, partially to take into account the rising price of high-fructose corn syrup.

Corn, which is used in PepsiCo’s Frito-Lay snacks, and in the syrup used in Gatorade and Pepsi’s fountain-drink business, make up about 2% of its global cost of goods sold. In an interview yesterday, food processor General Mills Inc. CEO Stephen W. Sanger said the increased demand for corn would likely cause a spike in the price of other commodities as farmers devote more acreage to corn.

“Corn isn’t a central item for us in the cereal world, but we use a lot of wheat in our cereals and dough, and oats are an important grain for us. We’ll look to offset those price increases with productivity,” Sanger said.

Last week the U.S. Department of Agriculture estimated that 10.5 billion bushels of corn will be produced from the 2006 harvest, the third-largest crop on record. As more ethanol plants are being constructed, the demand for corn is expected to grow.

Ethanol product totaled about 4.9 billion gallons last year, up from 3.9 billion the year before, according to the RFA. Next year, production is expected to reach more than six billion gallons.

Livestock producers, the nations’ single-largest corn customers, are being hurt by the higher prices. Production costs for pork producers have increased 25% from last year, according to Ronald Plain, an agricultural economist at the University of Missouri-Columbia.

At the end of last year, Tyson Foods Chief Executive Richard Bond warned that higher corn costs would eventually mean higher meat costs at the grocery store. Last week, Tyson opened a cattle-feeding facility in Argentina, and analysts say this move might signal the beginning of a trend in which higher corn prices in the U.S. push meat production overseas. “Ethanol is going to drive incremental investments related to the meat industry elsewhere,” says David Nelson, an agriculture analyst at Credit Suisse.

Food and beverage producers, too, are feeling rising cost pressure -- and in some cases higher corn prices are already trickling down to consumers. Bottlers for Coke and Pepsi are being buffeted by price increases in high-fructose corn syrup.