LITTLE ROCK, Ark. (KTHV) – How legitimate are those “sell by" or "use by" dates stamped on grocery store food products? Are those dates really required? If so, is the product then unsafe after that date?

THV11’s Dawn Scott is verifying what’s safe and what’s not.

Expiration dates are meant to help consumers, but they seem to cause more confusion.

To verify the importance, THV11 used several sources including the general manager at a local manufacturer, Hiland Dairy, to find out how a “best buy” date is determined. Another verify source included the head of nutrition at the University of Arkansas for Medical Sciences, who clarifies whether food is safe after the date. And here, the USDA lists guidelines.

THV11 began in Little Rock at Hiland Dairy which has been in operation in the Little Rock area for 155 years. Each day, Hiland Dairy churns out 150,000 gallons of milk. And on every single product, Hiland Dairy stamps a date.

"Our date is a ‘best before,’ we're trying to imply that it doesn't go bad on that date, it's just best before that date," said Mike Flagg, the general manager for Hiland Dairy.

Flagg admits figuring out exactly what the food product dates really mean can bewilder consumers.

"Very confusing, yes. We used to have wording on the date that made it sound like you needed to throw it out at the date so we changed it to best before to clear it up a little," said Flagg.

So, how is a date determined; Are dates required; And what do they really mean? Hiland Dairy runs a lab on-site and tests milk daily.

“We stress the product for a certain amount of time in our case it's 22 days and then we test the product four days out of date and we wanna make sure the product is still good at that. And by stressing it we keep the product we keep it at 45 degrees the full time where most people’s home refrigerators are 37 to 38 degrees," he added.

But are manufacturers like Hiland Dairy required to do this? THV11’s research verifies "product dating is NOT required by federal regulations," according to the USDA. "Manufacturers provide dating to help consumers and retailers decide when food is of best quality."

"Most foods are ok to eat after those dates," said Tonya Johnson, the Director of Nutrition Services at UAMS.

Johnson told THV11 the dates confuse people and it's unnecessary to toss foods based on product dates, it’s wasteful. "Unless it smells bad, looks bad, you know, probably there's no spoilage just if you go by that date," said Johnson. "A lot of food is going into landfills and it doesn't need to. We're discarding a lot of food, throwing away a lot of dollars."

This correlates to 161 billion dollars. In the United States, 30 to 40 percent of the food supply is left uneaten. But one non-profit, the Arkansas Food Bank, is working to tap into that supply.

"So, we'll take a lot of that food through our doors, we'll rescue that food that normally would go to waste if those grocery stores didn't sell it, instead they'll donate it to the food bank," said Tyler Lindsey, the Marketing and Public Relations Director at the Arkansas Food Bank.

The food bank quickly distributes certain foods like produce or dairy but keeps canned goods sometimes a year or more past the "use by" date. Nutritionists verify that such food is perfectly safe for consumption after the "use by" dates.

"What people need to look at is the ‘best by date’, that is when the food is at the highest quality, has the most nutritional value and tastes the best. It doesn't mean there's anything wrong with the food after the ‘best by’ date," said Johnson.

Flagg told THV11 that every batch they make, they will save a sample from it until it's out of code. "We average 90 to 95 percent passing at the stress. But when we keep it in a normal temp, I've drank milk 60 to 70 days out of code," said Flagg. The focus is not only on quality but safety as well. Flagg said it’s not in their interest to have products spoiling because that gives them a bad reputation and they don't want that, they want to over guarantee.

The only food product the federal government regulates is infant formula. Infant formula is sold with an expiration date. For more helpful information, including a Food Keeper's guide from the USDA on how safe foods are to consume after the "use by" or "best by" dates – click here.