Few things in the grocery store are more confusing than expiration dates on food products. When it says "Sell By 8/22/09," does that mean it has to be used by, or only sold by that date? Other products are even less clear, showing only a date with no explanation. Some canned or packaged products don't seem to have any date at all.

While most food processors date and code their products, the Food and Drug Administration mandates dating only on infant formula and baby food. Everything else is voluntary. Still, the food industry generally follows certain guidelines suggested by the FDA. Here's a quick overview of what all these food labels and dates mean:

Phrases like "Best Before," "Better if Used Before," or "Best if Used By" tell you how long the product will retain its best flavor and highest quality. These phrases are found on products like baked goods, cereals, snacks and some canned foods. The food is still safe to eat after this date, but may have changed somewhat in taste or texture.

The "Sell By" date is usually found on perishable foods like meat, milk and bread. This date guides the rotation of shelf stock and allows time for the product to be stored and used at home. The product is still safe and wholesome past this date. For example, milk usually will be good for up to a week beyond its "sell by" date if properly refrigerated. Meat that has arrived at its "sell by" date should be either consumed or frozen within 24 hours. You can also extend the useful life of milk and baked goods by freezing within a day or so of the "sell by" date.

"Expiration," "Use By," or "Use Before" are phrases that appear on yogurt, eggs and other foods that require refrigeration. Other dating terms are guidelines, but this one means what it says. If you haven't used the product by this date, toss it out.

The "Guaranteed Fresh" terminology is used for perishable baked goods. Beyond this date, freshness is no longer guaranteed, although the product may still be edible.

Some products bear a "pack date," indicating when it was packaged. This date often is encrypted so that only manufacturers, wholesalers and retailers can read it. The pack date on some products, such as eggs, is shown by a Julian date (1 through 365), January 1 is number 1, and December 31 is number 365. In other coding, letters A through M (omitting the letter I) are often assigned to the months, with A being January and M being December, plus a numeric day, either preceded or followed by the numeric year.

The point in all of this is that the fresher your food, the better it is. Processors want to assure customers that their products will remain at peak quality for certain periods of time.

Here's a tip: In a properly stocked store, the freshest items will be at the back of the shelf or underneath older items.

Copyright © 2009 Mary Hunt. All rights reserved. Permission to reprint required.

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