You’ve heard of pink slime. You know trans fats are cardiovascular atrocities. You’re well aware that store-bought orange juice is essentially a scam. But, no matter how great of a processed-food sleuth you are, chances are you’ve never set food inside a processing plant to see how many of these products are actually made.

Writer Melanie Warner, whose new exposé-on-the-world-of-processed-foods book, Pandora’s Lunchbox, is out this week, spent the past year and a half doing exactly that. In her quest to explore the murky and convoluted world of soybean oil, milk protein concentrates (a key ingredient in processed cheese) and petroleum-based artificial dyes, she spoke to food scientists, uncovered disturbing regulatory loopholes in food law and learned just how little we know about many of the food products on supermarket shelves.

Here are some questions that Organic Connections asked the author.

Q. The term "processed food" is ubiquitous these days. The food industry has attempted to co-opt it by claiming canned beans, baby carrots, and frozen vegetables are "processed foods." Can you help explain why a Pop-Tart is years away from a "processed food" like hummus?

A. You have to ask yourself, could I make a Pop-Tart or Hot Pocket at home with all those same ingredients listed on the package? How would you even go about procuring distilled monoglycerides and BHT, for instance?

Yet it is possible to make your own black beans at home by soaking and then cooking them. You could even attempt a rudimentary canning operation to preserve them. You can also make hummus by grinding chickpeas with a few other ingredients like lemon juice. The "processing" these foods go through is minimal and not disfiguring.

Q. Many people are put at ease when government agencies and the food industry state that controversial substances are "Generally Recognized as Safe" (GRAS). Why is this not as comforting as it sounds?

A. The GRAS process, as it's known, is one of self-regulation. If a food-ingredient company wants to introduce a new additive, they—not the FDA—hire some experts or a consulting firm to make the determination about whether this new ingredient is safe. Sometimes you’ll hear that company X has been awarded "GRAS status" for its new ingredient, but the FDA doesn’t award anything. The agency merely has the option to review what companies tell them.

Except when they don’t. In a glaring regulatory loophole that dates back to 1958, the GRAS system also happens to be voluntary. It's perfectly legal for companies to keep the FDA in the dark about new additives, and consequently there are some 1,000 ingredients the FDA has no knowledge of whatsoever, according to an estimate done by the Pew Research Center.

So although the FDA seeks to reassure us they are keeping a close watch over our food, the job of rigorously regulating thousands of food additives is simply too big for an underfunded agency. Brominated vegetable oil, for instance, the subject of a well-circulated petition by a 15-year-old in Alabama, was flagged for further study in the '70s, testing that was never done. And BHA, a "probable carcinogen" according to the Department of Health and Human Services, is still allowed in food.

Q. You investigated how soybean oil is made. Can you explain why calling it "natural" is a complete misnomer?

A. It’s not easy getting mass quantities of edible oil from soybeans, which are small, brittle beans containing less than 20 percent oil. First you have to drench them with hexane, a toxic chemical solvent that is known to cause nerve damage in humans. The hexane percolates through the soybeans several times and is then removed from the oil (any residues that remain are small.)

After that you have to treat the oil with sodium hydroxide and phosphoric acid, then bleach it with a filter, and deodorize it under heat and an intense vacuum. Then often the oil is hydrogenated or interesterified, allowing it to be more stable for frying or other high-heat conditions. Calling any of this "natural" is a farce.

Not to mention the fact that 93 percent of all soybeans are genetically modified, a technology most people think doesn’t deserve to go anywhere near the word "natural."

Q. On the topic of dairy, milk protein concentrates are a rather controversial ingredient many people are unaware of. What does the inclusion of milk protein concentrate in a food product say about it?

A. It says that the manufacturer is trying to cut corners and save money, which is understandable since all large publicly traded corporations are constantly under enormous pressure to cut costs. Milk protein concentrate can help replace the cheese that goes into boxed macaroni and cheese or the milk in processed cheese slices. If you see milk protein concentrate in your Greek yogurt it means the manufacturer has skipped the expensive step of straining the yogurt and has added milk protein concentrate, or MPC, to boost the protein levels (they’ve probably also added in some type of starch to thicken the yogurt).

Milk, regardless of what you think of its nutritional merits, is a real food. MPC is not.

Q. What is your answer to those who think "better-for-you" processed foods (such as fiber-enhanced protein bars and Omega-3 fortified cookies) are "a baby step" toward better health for Americans?

A. One word: Snackwells. In the early '90s, at the zenith of low-fat mania, Kraft introduced these "healthier" cookies. They had only 55 calories per cookie and much of the fat had been taken out (and replaced by emulsifiers, starches and gums). Eager for a hall pass on guilt, cookie lovers went nuts, buying up multiple packages and probably eating more than they would have otherwise, erasing any calorie reduction advantage. It’s a case that illustrates how "healthier" processed foods often don’t promote health; they just end up confusing people.

All these refurbished, less bad products only keep us tethered to a merry-go-round of inferior choices. The answer is making real food the foundation of our diets.