So how do food trends catch on, anyway?

Bacon. It’s everywhere. Wendy’s features it in the “Baconator” and Paula Deen crumbles it into quiche. Ditto for those deluxe cupcakes top-heavy with frosting. Is there a supermarket that doesn’t sell them?

Bacon and cupcakes–like sliders, bubble tea, popsicles, food trucks and chipotle–have caught on with consumers.

But how?

Food fads don’t always spread exactly the same way as other types of pop culture, such as fashion and music. Chefs don’t walk the runway at food shows holding up this spring’s hot pad Thai dish. There are no authoritative top-10 charts for food that show red velvet cake is No. 1 with a bullet.

But favoured foods items can go viral in the time it takes to upload a picture of salted caramel ice cream. The arbiters of trendy tastes include big-name chefs, bloggers, urban hipsters, eater tweeters and journalists. Usually they work in some hard-to-quantify combination.

“It’s kind of like trying to grab a jellyfish, in terms of trying to understand it,” said Ted Allen, host of the Food Network’s Chopped.

Food fads are older than the fondue pot in the back of your parents’ pantry. But the lines of dissemination were easier to track before the existence of the Food Network and the Internet. The high-brow authority was Gourmet magazine. Home cooks took cues from cookbooks and friends. There were just a few famous culinary authorities, like Martha Stewart.

Top-down authorities live on in the food world, even if they now share the stage with the cyber-masses. Serious eaters still are influenced by the magazines like Food & Wine and Bon Appetit. But the rise of food TV has dramatically multiplied the number of celebrity cooks who can popularize a food item. Think of what Bobby Flay did for grilling.

Television is widely believed to have kick-started the long-running cupcake craze, though celebrity chefs had nothing to do with it. Credit here goes to Carrie Bradshaw and her pals on Sex in the City, who treated themselves to the luxurious cupcakes at Manhattan’s Magnolia Bakery. Mainstream and social media took it from there.

The obvious difference now is how food blogs and food-centric websites offer more possible trends at a faster rate, whether it’s Epicurious listing “16 Restaurants that count” or a contributor posting a picture of tuna tartare on Foodspotting.

“Because of social networking, everybody is now a food expert,” said Phil Lempert, a food marketing expert who writes about the supermarket industry. “When you look at Yelp.com, when you look at Foodspotting, when you look at all the social networking tools that are out there, everybody is telling everybody about every food trend that exists. The rules have changed dramatically and you can get something going very quickly.”

Consider how social media helped bring food trucks into the fast lane.

Trucks serving burgers or gyros are nothing new, but the mania for hip, high-end mobile foods like Belgian waffles is more recent. The Kogi Korean taco truck in Los Angeles became the breakout star of the movement a couple of years ago. The fact that the food was creative and tasty made it popular, but Kogi’s use of Twitter to keep fans posted on the trucks’ whereabouts added to the buzz.

“If there were no Twitter, would the food truck trend be as large?” asked Food & Wine editor-in-chief Dana Cowin. “I think the answer to that actually has to be ‘No.’ Because before there was Twitter, there were food trucks: they were the local taco trucks … Once you hooked up Twitter and chefs and higher-end ingredients at a great value, you’ve got a perfect match.”

Old-school media played a role too. Newsweek in 2009 dubbed Kogi “America’s first viral restaurant” and the “food media elite,” as Allen calls them, wrote about it too. The result is that food trucks have become as ubiquitous as package delivery vans in downtown neighbourhoods from Miami to Milwaukee.

If there’s one food trend that illustrates how top-down and grassroots phenomena combine it might be bacon.

It likely started with chefs tossing bacon into dishes earlier this century to add a dash of umami flavour. That encouraged others to think of bacon as more than a just a complement to eggs. The movement gained sizzle through media exposure and word of mouth. It appears that it was not one big thing that led to the bacon Renaissance, but a bunch of smaller things.

For instance, in southern California about six years ago, Rocco Loosbrock paired peppered bacon with Syrah wine at a tasting. His “swine and wine” was such a big word-of-mouth hit it inspired him to go whole hog into bacon. Today, he sells bacon jerky, bacon chocolate, bacon coffee and more on his Bacon Freak website, part of a suite of bacon sites.

And perhaps it was simply inevitable, but there also are recipes online for bacon cupcakes.

“Bacon is one of the greatest things that was ever invented,” said Allen. “I think what has peaked is us discussing that fact.”