YOU MAY HAVE noticed in the supermarket that some food packages have more wrappings, seals and tapes than ever before. Food manufacturers haven't forgotten about the Tylenol tampering deaths of a year ago, and are redesigning packages with the tampering problem in mind.

"In most instances, companies have a great awareness of the problem and have taken steps to make packages more tamper-evident," says LeRoy H. Doar Jr., associate professor of packaging at Clemson University and a packaging consultant.

Doar likes to use the term "tamper-evident" because "there's no such thing as a tamper-proof product." Hugh Lockhart, a professor at the School of Packaging at Michigan State University, agrees. No matter how good the closure, notes Lockhart, "somewhere, one person may succeed in breaching the package."

The goal then, says Doar, is to design packages so tampering attempts will be clearly evident to consumers--a seal will be broken, for example, or an outer wrapping removed. In conjunction with such packaging, Doar advises manufacturers to warn consumers, in ads and on package labels, not to use a product if the outside covering is ripped or a band is not in place.

Most companies, however, don't like to publicize their anti-tampering efforts. According to Edward A. Merlis, vice president for public affairs for the Grocery Manufacturers of America, a Washington-based trade group, this is because firms fear the publicity will result in a tampering incident involving their products. Karen Brown, vice president for communications of the Food Marketing Institute, a trade group of food retailers, says companies are concerned that divulging the details of their activities will provide "sort of a blueprint of how to do it."

The Food and Drug Administration agrees, and declined to discuss ways in which companies are taking precautions against would-be tamperers. However, Jim Greene, an information officer for the FDA, noted that the agency is acting as an adviser to food companies interested in designing more tamper-resistant packages. FDA published a set of packaging regulations for over-the-counter drugs after the Tylenol incident, but it has not done so for food.

Greene explained that the drug rules responded specifically to the Tylenol crisis, but the agency does not believe it has the authority to publish the same rules for the food industry. However, the regulations for drug products, which describe acceptable tamper-resistant packages, have served as a guideline for the food industry.

The changes manufacturers have made in package designs are by now familiar to most consumers--tapes around bottles, cartons that are glued, foil coverings, film wraps and breakaway bottle caps. Many companies are still trying to decide whether other available designs are more effective than those currently on the market. However, he observes, "to do the job well takes fairly complex engineering principles."

Doar believes nothing new in packaging design needs to be invented. "What we have on the shelf is sufficient technology to render the vast majority of packages tamper-evident," he says.

Yet many products remain vulnerable to a tampering attack--products such as cottage cheese and yogurt, mayonnaise and peanut butter. "Companies are doing back flips trying to figure out what to do," Doar says, but notes that a packaging change is a multimillion-dollar undertaking for a product that is distributed nationwide. "They must do it right the first time," he points out.

Rep. Mickey Edwards (R-Okla.) recently questioned whether current tamper-resistant bottle caps are the solution for soft drinks. Most soft-drink companies use screw-on bottle tops attached to a band that requires the two to be broken apart for opening. Edwards complained recently to that FDA that a constituent had found that the caps on his six-pack of soda had been removed and replaced with substitutes. The caps were marked on the inside as part of a promotional game, and the constituent expressed concern that the games might promote not just sales but tampering.

An aide to Edwards says the screw-on lids can be easily removed without breaking the band, adding that this was demonstrated on the air by an Oklahoma television station after Edwards publicized the problem.

The FDA told Edwards in an Aug. 24 letter that it had "no basis for singling out foods with screw-top caps as posing more hazard than foods in any other types of packaging."

Edwards says California police recently reported a case of criminal tampering involving a soft drink in a screw-top bottle. A Cupertino, Calif., man became ill after consuming the drink, which he said was found to contain acetone, a substance found in nail polish. Edwards says the incident shows that FDA is ignoring "a very real danger to the public."

A survey conducted early this year by the Food Marketing Institute and Louis Harris and Associates found that nearly all of the 1,001 shoppers questioned said they usually check the packaging of the food they buy to make sure it is in good condition. "They felt the changes in over-the-counter nonprescription drug packages are worth the added cost," says Brown of the survey results. But she added, "We did not get a sense that consumers wanted an overhaul of food packaging in general."

Brown says the food industry's most positive action against tampering has been in working toward passage of legislation that would make tampering a federal offense, "a la hijacking." Currently, penalties for tampering vary from state to state, and in some cases it is only a misdemeanor. Bills imposing stiff criminal penalties for persons caught tampering or attempting to tamper with consumer products, including food and drugs, have passed the House and Senate, and differences in the two versions are expected to be worked out shortly. The legislation is supported by the Reagan administration.

Whether the new law would be an effective deterrent against tampering incidents remains to be seen. Many retailers have tightened in-store security as a way to discourage tampering attempts, Brown says. In the end, however, consumers can best protect themselves by being "consciously aware," says Doar, of the possibility of product tampering.