America can sleep a tad more soundly: The Agriculture Department finally has sorted out the confusion on the canned sweet potato front.

It wasn't easy, because these things never are, but the USDA's Agricultural Marketing Service has come up with new standards for grading sweet potatoes that go into cans.

No small potatoes, that. More than 50,000 acres of sweet potatoes are harvested annually for canning and the processors who do the job are governed by size standards established by the federal czars of "yamdom."

The dispute has been over the complicated formula that inspectors use in determining whether to stamp Grade A or Grade B on a lot of canned sweet potatoes.

It is so complicated that the published USDA explanation goes this way: "The new standards will change the criterion for determining uniformity of size by basing this factor on the 95 percent most uniform sweet potatoes, disregarding 5 percent or one sweet potato, whichever is greater."


"The idea is that a lot of people expect uniformity, especially the food-service industry, which relies on uniformity for portion control," said Harold A. Machias, a sweet-potato standards expert at the marketing service.

The standards are set by the USDA at the request of industry, which is under no obligation to follow them. But it makes sense to follow them because most federal, state and local governmental bid offerings for sweet potatoes call for specific grades.

The grading issue had kicked around the USDA for years, so in 1983, after hearing industry's views, Machias' office set a revised standard that was based on reviewing 90 percent of a can's contents.

In the view of some, however, the rule represented a regulatory bias toward large cans. The smaller can -- say, one that contained 10 sweet potatoes -- tended to be judged more strictly than the larger, gallon-sized can. The processors asked the USDA to take another look.

A new proposal went out for comment in August and, sure enough, there was a reaction because no one, not even the sweet potato connoisseur, seems to be in agreement about the meaning of Grade A or Grade B.

"It took considerable time to evaluate and work with the comments," Machias said last week. "We met with the industry, we heard from the sweet potato and yam commissions, we heard from processing plants. Almost everyone had a different idea about what we should do.

"This case was a little unusual because within six months of issuing a final rule in 1983, the industry was back asking to have it changed," Machias said. "So we have changed it, but I think the net effect is that we're going to go back closer to the old standard that was changed in the first place."

Why would anyone care that much?

Well, Machias said, "I think people are very concerned about the quality of the foods they buy. We are aware that our standards have to serve the public at large, but if we hinder the processor to the point where he has to charge a high amount just to stay in business, the consumer won't buy. But if you compromise the quality, the consumer won't buy either. You want to be equitable."

Issues of this sort are the nitty-gritty of regulation that sometimes keep regulators tossing at night. "I have a conscience about things like this," Machias said, "and, yes, you do take it home with you. Everybody does that, don't they?"