The Agriculture Department yesterday proposed two alternative methods of processing bacon to allow less sodium nitrite to be used in the curing process.

Nitrite is used to cure or preserve meats. It helps prevent botulism food poisoning and gives bacon, lunch meat and similar products a pink color and smoky taste. But when nitrite-treated meats are cooked, they produce nitrosamines as a byproduct. Nitrosamines have been blamed for causing cancer.

The new proposal by the department's Food Safety and Inspection Service would allow packers with approved quality-control programs to reduce sodium nitrite levels to 100 parts per million, down from the 120 parts per million now required.

"The proposal is in accord with an earlier National Academy of Sciences recommendation that USDA periodically review nitrite usage and maintain levels consistent with the latest scientific information," agency administrator Donald L. Houston said.

A second alternative would allow such plants to add lactic-acid starter cultures to sodium nitrite curing solutions. The starter cultures also help protect against organisms that cause botulism.

Under the proposal, the agency would continue its seven-year-old program of testing commercially produced bacon for nitrosamines.

The American Meat Institute suggested two years ago that the Agriculture Department reduce nitrite levels in bacon. But other groups -- the Western States Meat Association and the American Association of Meat Processors -- objected because they said it would be difficult to control nitrite levels precisely, the agency said.