You are forgiven if, because of all the current uproar over oppresive federal regulations and know-it-all bureaucrats, you didn't hear about the ground-beef caper.

It's not precise history, but the first alarms rang at the Department of Agriculture when a lonely sentinel cried out something like this: "There is hanky-panky in the hamburger."

But that was just a drop in the lunch bucket, it turned out, and more cries were heard: "Our pizzas are spinning away like wayward frisbies. Our mayonnaise is adorning unauthorized sandwiches."

And so it went, back in 1978, as USDA investigators found that millions of dollars worth of prime food products destined for school lunchrooms simply were not getting there.

Practitioners of free enterprise, it appeared, were making all-too-liberal interpretations of the term.

USDA's school-feeding program, one of the most complex in government, provides more than $600 million a year in commodities -- meat, flour, cheese and the like -- to school lunchrooms.

One of the reasons it is complex is that many schools have no way to handle the bulk commodities comfortably. So USDA allows them to have the federally donated food converted into more easily used products.

Flour, cheese and tomato paste, for example, are turned over to a processor, who converts them to pizza. Huge blocks of ground beef go to the processor, who makes them into patties and sends them back to the lunchroom.

The processor makes money for his work. The schools get the finished product at prices well below what they would pay if they had to buy pizza without Uncle Sam's ingredients.

During the last decade, schools have moved increasingly to this system. Federal flour becomes bread, crackers, rolls. Soybean oil becomes mayonnaise, and so on. USDA officials estimate that as much as $150 million of the federal commodities go through this processing.

The success of the program depends on a number of things. Guarding against fraud and waste is one of those things, and regulations adopted back in 1958 were intended to do so.

But basic honesty and good faith are equally important in making it work. When those elements begin breaking down, you're talking about more federal regulation.

It often starts with that lonely sentinel sounding an alarm -- be it in the lunchroom, in an auditor's cubicle or on the bank of a polluted stream. Regulation is almost sure to follow.

All of which is preamble to new USDA regulations that will apply to 38 states and about 425 private food-processing companies, which won't like it but will have to live with it.

The Food and Nutrition Service in June published proposals to tighten monitoring of the food-processing system, force the companies to keep better records and establish penalties for abusers of the system.

Because of the alarm someone sounded and the story of ripoffs that unfolded as a result, the USDA rules revision will affect a major part of the school lunch industry.

Most of the proposals are linked to findings of the USDA inspector general, who issued a lengthy report last year outlining a startling picture of processing firms playing fast and loose with the federal food.

Some of the findings:

Twelve of the 18 processors randomly investigated could not account for $3.4 million worth of food. Some of it had been sold to commercial outlets, rather than returned to the schools.

Two processors substituted lower-grade ground beef they had on hand for $250,000 of federal beef and sent it back to the schools.

Misleading labeling, inadequate record-keeping and haphazard state and local monitoring prevented schools from knowing if they were being shortchanged.

In its sampling of processing programs, USDA investigators could only estimate the losses. Projected nationally, they undoubtedly would run into many millions of dollars.

How could it happen? Why was there no outcry? Why were the 1958 regulations so lax, and then not tightly enforced?

"We encourage processing, but we didn't want to be too restrictive on the schools," a department official said. "We didn't have close monitoring; we took a sort of hands-off policy. We had a staff shortage, program growth was gradual, and frankly, we were getting no bad reports back from the schools."

In other words, it might be said, USDA trusted people to do right. Now there'll be a regulation requiring it.