Once the vanguard of cool, food trucks may soon be fried

• Larissa Dubecki's fantasy food trucks

They've been among the hottest food trends for several years now, but is Melbourne's love affair with food trucks cooling down? The city could be at saturation point for the street food sold from the vans, which mostly target inner suburbs.

According to smartphone app and website Where the Truck At, 52 vans are operating across Melbourne - a number that hospitality industry expert Ken Burgin, from Profitable Hospitality, doesn't believe is sustainable.

''Melbourne pioneered the industry with some pretty groovy businesses, and the novelty was pretty exciting,'' he said. ''It's great as a place for innovation in food, but the romance and the glitter is not the reality.''

What appeared to be a cheap way to get a foot in the industry could be expensive, Mr Burgin said. Council permits, staff wages and handling perishable stock can be financially challenging when customers expect to pay little more than loose change.

Complying with strict hygiene rules, potential parking fines and other trucks encroaching on a popular spot were also risks, he said.

Mr Burgin said most trucks now concentrated on events. Taco Truck and Beatbox Kitchen were among the first that helped spark the craze five years ago, and owner Rafael Rashid said his four trucks were as busy as ever.

He said there were ''possibly'' too many trucks in a concentrated area but a lack of co-operation from local governments on permits and respect between operators were bigger issues.

In a sign of perhaps tough times, online site Gumtree lists seven trucks for sale in Melbourne.

David, who didn't want his surname published, is selling his truck and trading-site permit in Melbourne's south-east. He said if a popular site could be found, it could be profitable, but parking fines and other infringement notices added up.

At Carlton North on Friday evening, resident Brook was visiting Beatbox Kitchen. ''I think they're [the trucks] good, but I don't know if the trend's still hot right now,'' he said.

Just a handful of local governments allow food trucks; lobbying from cafes and restaurants, concerned that the trucks will take business away, has limited permits.