What are they adding to pull this off? Hostess is mum on their new recipe, saying only that they’ll achieve longevity by shipping some of their cakes frozen—but that practice is something they did in the past anyway. Steve Ettlinger, a New-York based writer and the author of Twinkie, Deconstructed, thinks it isn’t the recipe that’s changed, but rather, the packaging. He points to an article he wrote for The Atlantic, which explains how a packaging redesign could be what’s keeping the cakes moister longer. So while it may appear that the Twinkie was not re-engineered to extend its shelf life from 25 to 45 days, the return of the Twinkie—and the feeding frenzy around its comeback—has to raise the question of why we’re so smitten with them in the first place? What makes these manipulated foods so irresistable to our humble taste buds?  “Twinkies are typical of all processed food,” says Ettlinger. “The bulk of the ingredients in Twinkies are flour and sugar; the artificial ingredients are limited in amount but potent in effect.” Before you deem “processed food” to the realm of convenience snack foods, know this: You’d be hard-pressed to eat anything that hasn’t been altered or modified. “There are very few foods that can be consumed without manipulating it one way or another,” says Kantha Shelke, PhD, a scientist and principal at Corvus Blue LLC and spokesperson for the Institute of Food Technologists. “Grains, fruits, vegetables, meat, and dairy all have to be processed—cleaned, sorted, peeled, pounded, cooked, pasteurized, and treated in some way.” In fact, 77% of eating occasions involve at least some processed food, and 42% involve all processed food, she says. And this isn’t something new. As Ettlinger points out: “We’ve been processing food to make it last since the beginning of time with salting, smoking, cooking, and drying.” From a manufacturing standpoint, this is a good thing. It means our food supply is safer than ever before and it offers unprecedented variety, convenience, consistency, and affordability without fear of adulteration or spoilage, says Dr. Shelke. The downside—you knew this was coming—is that while the ingredients and technologies added to foods satisfy FDA requirements, food processing requires extensive cleaning, which rids products of other nutrients, she says. And then there’s the issue of taste. With the advent of science and technology, the palates of people around the world have become more sophisticated and discerning, says Dr. Shelke, making taste a very important element in the business of food. “Food businesses, however, focus on the emotion and functional needs, like enjoyment, hunger, thirst, and comfort, and then focus on ensuring that the product tastes and looks good to ensure repeat purchase,” she says. In other words, says Ettlinger, “the processors have managed to create foods that appeal to our basic cravings for salt, fat, and sugar.” It’s what authors of Rich Food Poor Food Mira Calton, CN, and Jayson Calton, PhD, identify as a “bliss point.” “Food science is working at a whole new level,” says Dr. Calton. “Teams of food scientists are hired to create a bliss point, or the right taste and texture, that enhance flavors.” To the Caltons, the only advantages processed foods have are negative ones. “Everything is manufactured to make you eat more,” says Dr. Calton. “Just like Wall Street has a market share, food manufacturers have a stomach share. Their goal is to acquire as much stomach share as they can by using science and ingredients to get consumers to a point they can’t say no.” “It’s a very sad fact,” adds Calton. “You hear that we’re all looking for healthier options, and yet what people are really excited about is getting another snack food.”  More from Prevention: 7 Shocking Food Frauds