By: Lea Winerman

After several years of high-profile salmonella outbreaks involving eggs, peanut butter and other foods, the Senate on Wednesday moved forward with the most significant food-safety bill in 70 years.

If it passes, the bill would expand the Food and Drug Administration's power to oversee domestic and imported food and to order mandatory recalls. It would:

• Give the FDA mandatory recall authority: Right now, the FDA can only request that companies voluntarily recall tainted food. The new law would give the agency the authority to make mandatory recalls.

• Require more frequent inspections: The law would authorize the FDA to hire more inspectors, and would increase the frequency of inspections at food manufacturing and processing plants. Facilities identified as "high-risk" based on the type of food processing done there, the facility's safety record and other factors would be inspected at least once every three years. Non-high-risk facilities would be inspected at least once every five years.

• Require new prevention plans and record keeping: The law would put a new responsibility on food processors and manufacturers to develop "science-based" plans to identify and avoid potential safety hazards, to keep records of their preventive safety measures, and to make those plans and records available to the FDA when requested.

• Add new rules for food importers: The law would set safety standards for imported food and would require importers to verify that those standards are being met.

Senators voted 74-25 Wednesday to end debate on the bill -- with 16 Republicans joining nearly every Democrat. The measure could come up for a final vote by Friday, and Majority Leader Harry Reid, D-Nev., has threatened to keep the Senate in session through the weekend if the bill's opponents don't let it come up for a vote before then. Some Senate Republicans, including Sen. Tom Coburn, R-Okla., have said that the $1.4 billion bill will be too costly.

The bill has gained wide support from consumer groups, large food growers and food processors. But many supporters of small, local growers have opposed the bill, saying that the new reporting requirements will be too burdensome and unnecessary for small farmers who sell their food locally. On Wednesday, Democrats and Republicans reached a compromise on an amendment offered by Sen. John Tester, D-Mont., that would exempt small farmers that sell their products locally and earn less than $500,000 in yearly sales.

For more on food safety:

In September, the NewsHour health unit reported on the major egg recall and talked to FDA commissioner Margaret Hamburg about her support for the new law.

And in 2008, after a salmonella outbreak was tied to imported Mexican peppers, the NewsHour science unit reported on how the CDC and FDA track down the source of food borne illnesses.