San Francisco Chronicle food writer Jonathan Kauffman has a story to tell about how formerly fringe foods like hummus, tofu, and granola entered contemporary American food culture. In his 2019 book Hippie Food: How Back-to-the-Landers, Longhairs, and Revolutionaries Changed the Way We Eat, he explains that the history of fringe food dates back to the mid-nineteenth century and people such as Sylvester Graham, creator of the graham cracker.
Los Angeles was a health food hotbed where a cornucopia of culinary and spiritual movements sprouted. (Actress Gloria Swanson, best remembered for her role in Sunset Boulevard, was an early champion of clean eating.) From the 1920s to the 1950s, several foods that were later associated with hippies — sprouts, smoothies, carob — were introduced although they didn't become popular until the mid1970s, when people such as Anna Thomas (The Vegetarian Epicure) and Mollie Katzen (The Moosewood Cookbook) wrote influential, internationally-influenced cookbooks.
Kauffman cites the summer of 1970, when the airline industry in the US, spent millions of dollars to upgrade airports for jumbo jets, increasing the capacity for travel and offering cheap fares to Europe. American kids flocked to European countries and brought back simple dishes that hadn't been widely known in the States.
Tofu has been made in California since the mid-nineteenth century. In 1971, a UC Berkeley student, Frances Moore Lappé, dropped out of school to research the roots of poverty. Reviewing agricultural reports, she discovered we were feeding huge amounts of corn, grain, and soy to animals instead of people. In fact, she determined that if we went vegetarian, we could eliminate global famine. For her, soybeans were the perfect protein. William Shurtleff and Akiko Aoyagi wrote The Book of Tofu, and spent six months traveling the United States setting up tofu collectives. Kauffman attributes the longevity of these foods to ideas that sprung up in the 1970s.