When it goes into effect, Assembly Bill 660 will require the use of two standard terms for food products that choose to use a date label—"best if used by" to indicate the quality date of food, or "use by" to indicate the safety of food.

Newsom said in a statement he also believed the new law, which he signed on Sept. 28, would better inform consumers and "significantly reduce food waste."

Stamping food with quality or time limits is not required as part of the law. The federal government also doesn't require foods to be issued a "use by" date on anything except baby formula.

Environmental organizations that sponsored the new law say banning the "sell by" stamp will keep more food out of the garbage bin, cutting down on methane produced at landfills.

The groups also hope the new law will cut down on confusion by requiring manufacturers to use the same phrases for date labels on all products.

California is the first state in the nation to pass the regulations, which were written by Assemblywoman Jacqui Irwin, a Thousand Oaks Democrat.

"Having to wonder whether our food is still good is an issue that we all have struggled with," Irwin said in a statement.

"Today's signing of AB660 is a monumental step to keep money in the pockets of consumers while helping the environment and the planet."

With the new law in California, dates may be voluntarily applied to meat, poultry, and egg products, provided that the dates are truthful and not misleading.

Irwin said some of the phrases currently used, such as "expires on," "best before," and "sell by," can be unclear to average consumers. Some consumers may think the dates are equal to expiration dates, she explained in a legislative assessment of the bill.