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All-you-can-eat? Research focuses on all that you waste

food waste photo from Mizzou video
University of Missouri-Columbia

You have leftover French fries on one plate and leftover beef ravioli on another.

Sure, it’s not the most balanced meal, but that’s not your concern. What you want  to figure out is this: Which will have the bigger impact on the environment when you toss it into the trash? And how can that impact be reduced?

Research led by Mizzou Professor Ron McGarvey addressed that question in his latest study of food waste at those popular all-you-care-to-eat buffets.

McGarvey, who teaches both industrial engineering and public affairs, said most analysis of the environmental cost of food waste has looked at the consumer side of the question, what he called “the clean your plate sort of public announcements.”

He approached the problem from a different angle.

“I saw that there was quite a lot of food waste that was occurring back in the kitchen, on the production side of the operation,” he said. “It was really being aware of those two pieces that brought the topic to mind.”

In a restaurant where you order what you want to eat, operators have a better way to anticipate demand and limit waste, McGarvey said. But the all-you-can-eat operations, where patrons can help themselves to a variety of choices, with unlimited portions, present a different challenge.

“In a standard environment,” he said, “we have production planning tools that help us identify what you lose in terms of revenue for a lost sale. If you run out of cheeseburgers, and you made $1 per cheeseburger, you have an idea of what the cost is to you of running short. 

“You don't really have a parallel in these all-you-care-to-eat, buffet-style operations. Because if they run out of cheeseburgers, there's no lost revenue associated with that. They weren't going to get any more money by serving an additional one.”

The planning process becomes a delicate balance of two objectives, he said.

“There’s the desire to not overproduce,” McGarvey said, “because overproduction in food service is usually associated with waste. And so you’d like to avoid producing more than what demand is, but there’s a similar desire to avoid underproduction, to avoid shortfalls for food.”

And with some items, like meat, whatever isn’t eaten one day may be frozen and used later in another form, like chili or tacos. Fried foods are different, McGarvey said, because they have a shorter shelf life.

“They cook it,” he said, “and whatever isn't served or consumed has to get thrown away.”

Combine the supply-and-demand problem with the environmental costs of producing food, and the issue takes on a new complexity.

“Whenever you throw away a pound of chicken,” McGarvey explained, “you’re not just throwing away a pound of chicken. You need to think about all the resources that were necessary to grow that chicken, turn it into meat and then deliver that meat to you.”

Filet mignon or potato peels

And when that meat goes to waste, additional environmental factors enter the picture, like hauling the garbage away.

“In terms of trash hauling,” he said, “a pound is a pound. You pay the same for a pound of filet mignon as you would for a pound of potato peels. 

“If you include the environmental impact of the wasted food, all of a sudden, throwing away a pound of beef is a lot worse than throwing away a pound of tomatoes or a pound of cheese.”

The latest research by McGarvey’s team grew out of an earlier study on the relative environmental costs of plant-based foods versus meat-based dishes. The research included students who were paid to conduct “trash audits” of food that came out of campus dining services.

Mizzou Professor Ron McGarvey
Credit University of Missouri-Columbia
Mizzou Professor Ron McGarvey

Now that McGarvey and his colleagues have looked at the problem from the production side, his next step will look at how the use of leftovers affects the environmental costs.

For restaurant owners and their patrons who show up hungry, the answers may change how all-you-can-eat operations are run.

“What's the penalty that you pay for running out of an item?” he asked. “We're able to show them that based on the decisions that we're making, if you ask somebody at this kind of facility, what's your shortfall cost, what do you pay whenever you run out of an item.

“The typical answer is I don't know. It's not something that people think about, because it doesn't really appear on a balance sheet.”

Follow Dale on Twitter: @dalesinger

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