As beginnings go, it could hardly have been more humble, just an old filing cabinet with wheels welded to the bottom, its name plastered optimistically on the side, selling souped-up yoghurts and smoothies to grumpy commuters as they herded off the morning train at Waterloo East. Hardly, too, the sort of thing that a management consultant would give up the nine-to-five for and a career with the industry giant Bain and Co.

But mOma was destined for bigger and better things. If you’re a London commuter, you’ve probably spotted the distinctive carts in Waterloo, London Bridge or Victoria, indeed in any one of the eight outlets that mOma has reached since its debut in February 2006.

And if you haven’t, then you very possibly will, for Tom Mercer, its founder, plans to open another eight next year and to expand the company beyond its London base by selling its products through Ocado, the internet grocery retailer, from September. The products are also sold in Selfridges’ food hall and are served on Virgin Atlantic flights.

The secret, he says, is in mOma’s oats. Jumbles — oats soaked in apple juice and mingled with low-fat yoghurt and fruit — and Oaties — smoothies with oats — help to keep hunger pangs at bay longer than their non-oaty competitors, according to Mr Mercer. He should know, having spent five months testing oat, yoghurt and fruit mixtures in his flat in Waterloo before looking for a suitable location for his first outlet.

By then, he had decided that life as a management consultant was not for him. “It [Bain] was a great company but not really my calling,” he said. “I always wanted to do my own thing. I’m from a farming family and my Dad and brother run their own businesses.”

The idea for mOma came from one too many trips into work on an empty stomach. “I wanted to have good stuff for breakfast. I used to blend up smoothies at home and throw in oats, then I thought: ‘Wouldn’t it be great to sell to people just at breakfast time?’ ”

The moMa stalls are relatively easy to find space for, as they do not use any water or electricity, and they give extra rent to those running the railway station without taking up a large space permanently. “There has been a lot of restructuring in stations, with lots of shops taken out to make more open space and give other areas for people to walk,” Mr Mercer said.

The earliest mOma products were sold to commuters in used plastic water bottles with labels glued on. Mr Mercer asked everyone who bought one to e-mail him with their thoughts on the mixtures, including his personal favourite Wild Berry Jumble.

Now the breakfasts are prepared in Deptford, South East London, then driven into Central London and sold at the stalls between 6.15am and 10.45am, to catch the morning traffic. There are about ten people working at the stalls, mainly students who want to earn a little extra before going to lectures, although Mr Mercer often pops up to serve his customers himself. After the morning’s work, the driver picks up the stall workers and any leftovers. From being a one-man band a few years ago, mOma now employs 25 people in total, five in the office, another five in the kitchens and the drivers. One of the company’s main challenges is continuing innovation of the product range. The company also makes the HodgePodge, a layer of fruit cooked with spices, yoghurt and a packet of granola.

But the move into selling to supermarkets and to consumers outside London has presented new hurdles to overcome, particularly the need to make food that will not go off within a couple of days but still preserving the emphasis on fresh fruit.

“It’s a huge, huge area to keep trying to innovate while trying to sort out the commercial aspect,” Mr Mercer said. “Some of it’s about ingredients and some about environment and pasteurising.”

One of the business’s strengths is the loyalty of its customers, a testament to its branding as a healthy alternative. Innocent, its much bigger competitor in the smoothie market, has managed to carve out a large niche and make its founders into paper millionaires — with mOma’s launch on a wider scale, Mr Mercer is aiming at similar heights.

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