Why Soy Is Everywhere

In Asia, it has dignity. In the United States, it still lurks in the culinary shadows.

Stinky tofu or chou doufu in Wangfujing Snack Street in Beijing, China.
Stinky tofu, or chou doufu, in Beijing on May 23, 2011.

Soy, light of my life, temptation of my taste buds. My sin, my soul. You put the bite in my chik’n nuggets, the creaminess in my soy lattes, the chew in my tofu scramble that all but convinces me that I’m eating something that came out of a chicken. You make it possible for me to enjoy burgers, sausage, chorizo, hot dogs, and chili on a near-daily basis. Thanks to you, not once have I felt left out while my friends chowed down on cow flesh. You are the chameleon of foods, the ultimate imitator, the snack of all trades. For vegetarians like me, you are a culinary miracle.

If you aren’t vegetarian, lactose-intolerant, or a lover of Asian cuisine, you may not share my appreciation for this humble legume. In fact, you may not think soybeans have much of an impact on your life at all. You would be wrong. It turns out soy isn’t just good at making fake meats more meat-like—it’s the secret ingredient making all processed food more, well, food-like.

I found this out a few years ago, when I dipped my toes into the underground world of veganism. As I began paying more attention to ingredient labels, I realized something strange: Soy showed up in a baffling array of foods, from hot dogs to salad oil to Oreos (which are, incidentally, vegan). A quick scan of a McDonald’s ingredients list revealed soy in more than 200 items—and not just in expected things like French fries and chicken nuggets, but also breakfast sausages, grilled onions, chicken patties, BBQ ranch sauce, sesame buns, liquid margarine, cinnamon melts, hash browns, griddle cakes, chocolate chips, and bagels. (At Taco Bell, it’s the same story.) Forget Dunkin’, I realized: America runs on soy.

The weird thing is, people aren’t the main consumers of soy—not even close. More than 85 percent of soybeans get crushed and milled into animal feed. The result is highly inefficient: Instead of feeding a high-quality protein to humans, we are first feeding it to our livestock, and then eating the protein in their meat. That means in order to produce 1 kilogram of animal protein, we have to feed livestock almost 6 kilograms of soy or other plant protein. In fact, experts estimate that we could feed at least 800 million more people if we just fed them the grain we usually feed livestock.

Not the most logical way to feed the world, right? “It’s essentially a protein factory in reverse,” says Peter Golbitz, a soy industry consultant who founded food consulting firm Agromeris and chaired the World Soy Foundation.

But at least the food industry has been remarkably resourceful in finding uses for the excess soy oil and other waste products created by turning food into feed. In America, we’ve treated the soybean like a used car by stripping it for its parts: We’ve found that fatty compounds in soy could mimic eggs, stretch protein, and prevent separation in peanut butter; we’ve distilled soy’s protein to fortify Cheerios, pump up protein bars, and keep chicken breasts plump. So what exactly were these soy products, and what are they doing in all our food?

Soy oil: This is far and away the most ubiquitous oil we eat, as well as the most common way we get our soy, in a drastic change from the past. In 1909, soy oil was virtually nonexistent in our food supply. By 1999, it had skyrocketed from 0.006 to a whopping 7.4 percent—a 123,810 percent uptick.* Today we eat so much of it that researchers at the National Institutes of Health have been able to detect traces of it in our hair and fingernails. “This explosion in soy consumption occurred throughout the 20th century as an uncontrolled experiment,” says Joseph Hibbeln, a nutritional neuroscientist at the National Institute on Alcohol Abuse and Alcoholism. “We’d prefer to test it.”

One technological innovation made it possible for us to reap the oily benefits of all that soy: hydrogenation. Normally, soy oil is awful for frying: It’s unstable, has a low smoke point, and goes rancid fast, says Lisa Mauer, a food science professor at Purdue University. But at the turn of the century, clever food scientists figured out how to make some of the unsaturated fatty acids in soy oil into saturated fatty acids through partial hydrogenation, making soy oil far more stable. (Hydrogenating oil all the way would result in a solid, waxy fat like margarine; partially hydrogenating it merely improves its flavor and stability.) That’s why, today, you can leave your soy oil in a 280-degree fryer in the back of a McDonald’s for hours on end.

But as partially hydrogenated soy oil seeped into everything we eat—from packaged cookies to peanut butter to vegetable oil-based margarines and even crayons (OK, only preschoolers eat those)—we realized that maybe that wasn’t such a good thing. This kind of oil adds trans fats to food, which we’ve known since the 1990s could contribute to heart disease. So in the past decade, we’ve drastically cut down on the amount of hydrogenated soy oil in our food. “There has to be a balance between health and sensory qualities for consumers to accept a product,” says Mauer. Of the 18 billion pounds of soybean oil we consume in the United States, about 2 billion pounds are partially hydrogenated, down from a high of 8 billion pounds in 2005, according to the United Soybean Board.

Soy protein isolate: Ever see grilled chicken breasts that still appear fresh and juicy even though they’ve been sitting out at the salad bar for hours? Soy protein isolate is the magic ingredient. By binding fat and water, it keeps chicken breasts, salami, ham, and other processed meats in “a nice, chewable product,” says Golbitz, who also founded Soyatech, a research and publishing firm that consults for the soy industry. Think of it as chicken Botox: Food processors inject it into chicken meat along with salt and water using hundreds of tiny hypodermic needles, says Golbitz.

Soy protein isolate is basically what it sounds like: the protein that remains after you strip soybeans of their fat, sugar, and fiber. In chicken breasts, it keeps the brine mixture from leaking out, so the meat stays plump. It’s also used in cafeterias and Taco Bells to prevent troughs of ground beef from separating into unappetizing layers of meat and grease when stewing in the fryer. It’s added to energy bars for nutrients and chewiness and is a major source of protein in nondairy baby formula. Finally, in veggie burgers, it creates a chew akin to flesh. After all, when you bite into your Boca Burger, “the last thing you want is a piece of shoe leather,” says Golbitz.

Soy lecithin: Lovers of chocolate, this is the ingredient to thank for your smooth, creamy Hershey’s bar. Soy lecithin is used in virtually all chocolate to add “a better mouthfeel,” says Eric Gurzell, an assistant professor in dietetics at Western Illinois University. It helps “keep particles of sugar suspended in the cocoa butter,” writes Thor Hanson in The Triumph of Seeds. Mm, particles.

But it’s not just in chocolate: Soy lecithin is in a variety of desserts. Why? As any baker knows, soft, pillowy baked goods get their goodness from emulsifiers—things like eggs that prevent ingredients from separating while adding volume and texture. Chemically, emulsifiers are made up of fatty compounds called lecithins, which are derived from phospholipids in cell membranes. These lecithins can be found in animal products as well as any fatty plant, like sunflower seeds—but the cheapest and easiest way to get them is from soy.

Soy lecithin is everywhere, in peanut butter, margarine, frozen pizza, and non-stick cooking spray. McDonald’s even sprays it on slices of American cheese for “slice separation.” In all these foods, it’s used in tiny amounts. “It’s just a processing aid,” says Golbitz. “We’re talking about a very small, incidental ingredient. There’s not enough to give you any nutritive benefit.”

Soy flour: The same enzyme that makes soy taste beany has another useful property: It bleaches. For this reason, soy flour is added to your Wonder Bread to turn it that appealing white color. (Soy is also an ingredient in cosmetics that lighten skin.)

Soy flour is the basis of textured vegetable protein, a vegan meat alternative sold in bulk at health food stores in the form of slightly cereal-y, cardboard-y flakes and is so remarkably meat-like that it’s often used as a filler to “extend” meat, especially in mass-feeding situations such as in schools, hospitals, and prisons. Not everyone is thrilled about that. Chicago and Florida prisoners have sued their states for feeding them “soy-enhanced ‘meat entrees’ ” without asking. They claimed the secret soy had given them “soy-induced stomach pain and bloating.” Golbitz, however, is skeptical: “I don’t know what kind of health problems a person would have, other than a little possible extra gas.”

* * *

Clearly, soy has become an invaluable asset to the food industry. Whenever you need to mimic meat or dairy on the cheap, just turn to soy. But how did we end up wringing all these ingenious compounds out of one humble bean?

The story begins in Asia. Farmers there recognized thousands of years ago that the soybean—versatile, pest-resistant, affordable, and nutritious—made an ideal crop. Moreover, it provided a rich source of protein complete with all eight essential amino acids. As a result, it became a cornerstone of many Asian diets. Chefs have transformed soy into tofu, yuba, soy milk, and fermented products like miso. Rather than being a cheap meat substitute, tofu holds its own in traditional dishes like Ma Po tofu (rough translation: “pockmarked grandmother’s tofu”). The Japanese call it the royal bean; the Chinese call it the big bean.

In Asia, in other words, soy has dignity. But in America, something was lost in translation. After botanists brought hundreds of strains of the soy plant across the Pacific, none other than car pioneer Henry Ford became one of soy’s first great promoters. Ford became “America’s No. 1 soy bean man,” calling it the food of the future and wearing soy silk ties and suits to advertise its versatility. Unfortunately, the rest of the country didn’t share his enthusiasm. In America, that same texture and unique beany taste that made soy so popular in Asia rendered it “the vilest thing ever put into human mouths,” as one of Ford’s secretaries put it. Almost a century later, the stigma remained. Tofu and other soy products were relegated to Asian grocery stores and hemp-y health food stores, and deemed “dull, bland hippie food.”

So is soy doomed to lurk forever in the shadows, invisible and underappreciated? Not necessarily. Today, more and more Americans are welcoming soy as not just an additive but as a food in its own right. According to the Soyfoods Association of America, from 1992 to 2011, tofu sales increased from $108 million to $255 million. In 2012, tofu spread into school cafeterias nationwide after a new federal USDA rule made it an officially acceptable substitute for meat in school. And in 2013, Chipotle became the first national fast food chain to add tofu to its menu, in the form of the spicy filling Sofritas. All this is still a drop in the bucket compared to the amount of soy that goes into feeding livestock—but it’s a start. Soon, it seems, America may be ready to open its hearts and mouths to soy in its full, beany glory.

Correction, May 21, 2015: This article originally misstated that in 1909 soy oil made up 0.0006 percent of the American diet. It made up 0.006 percent. (Return.)