The supermarkets may have been trumpeting their healthier credentials and their green aspirations, but they seem to have overlooked one aspect of their operations - their in-store cafés.

In a foodservice world dominated by trendy eateries such as Yo Sushi!, Eat and Carluccio's, the traditional supermarket café looks positively archaic with its £1.99 all-day-breakfasts and burger and chip combos.

While takeaway style food is figuring ever more prominently in the grocery mix, own-label grocery brands play virtually no role in the in-store café. But things are slowly beginning to change. Supermarkets are opening up more and more swanky cafés, hot food-to-go counters and even wine bars - so much so that some are beginning to resemble upmarket food halls rather than supermarkets.

One of the retailers leading the revolution is Marks & Spencer. It is extending its Eat Over Deli format alongside its Café Revive format and expanding its number of large restaurants with the aim of creating a foodservice offer that is a destination in its own right and really reinforces its grocery credentials. The best expression of this is arguably its Canterbury restaurant, which is located immediately next to its food hall, and has its own street entrance.

M&S has also gone a step further than its pure supermarket rivals into the takeaway market. It currently has 12 hot food-to-go counters selling everything from porridge and bacon rolls to pizzas, baguettes, soup, Singapore noodles, chips and bagels.

M&S is using its various café formats to "bring new foods to people", according to Claire Wilkes of the hospitality PR team. "It's an area of opportunity, which is all about enhancing the food offer to our customers".

M&S arguably has more of an imperative to improve its existing offer than its pure supermarket rivals in the sense that it is competing in the cut-throat world of the high street. But others are catching on.

Waitrose, for instance, has six café formats, including three coffee bar formats. At its Food & Home store in London's Canary Wharf there are numerous eating and drinking options including a wine bar, sushi bar and a counter serving juices and smoothies. Waitrose is unusual in that it is part of the John Lewis Partnership and can therefore think like a department store when it wants to, but it has definitely raised the bar.

"In-store catering is getting more interesting, particularly with Waitrose at Canary Wharf," says Peter Smale, co-founder of catering consultants Turpin Smale.

Rachel Pearson, central buyer of foodservice for Waitrose, adds: "It is not only people who have shopped in the branch that visit our coffee shops. Many pop in for a sociable drink to relax and meet with friends."

It makes sense for M&S and Waitrose to give their in-store foodservice offers a more upmarket feel, given their relatively well-heeled customer bases. But even the supermarkets with broader demographics are now sharpening up their offers.

The key is tailoring them to fit. Sainsbury's is customising three café formats to individual stores, taking into account demographics, store size, location, and customer shopping journey. Where one of the standard café blueprints is unsuitable it will fit a breakfast bar or coffee bar instead.

Sainsbury's also boasts several internet cafés. "We are improving the environment, our offer and the service to convert more customers to using the in-store cafés," says Julia Hatcher, category manager for restaurants at Sainsbury's. "Our new look is attracting a much wider customer base. It's been a great challenge to design a concept that attracts new customers without alienating existing ones."

Asda has a more contemporary-looking café, which Mark James, general manager for food services, says has become a particular draw for customers who drive to the store. Such is its success that the new-look café will be rolled out to all new Asda stores. Morrisons has a 'My Cafe plus' variant with a smaller footprint offering a reduced menu with light snacks and hot and cold drinks.

Healthy eating is becoming an increasingly important focus. Sainsbury's has a main meal from its Be Good to Yourself range available each day along with three sandwiches from its healthy eating range, Morrisons has recently introduced a healthy eating range, Asda has a Great Stuff kids offer along with Good for You! meal offers, and Tesco is using flash messages in its cafés to highlight the healthier meal options on its menus.

In-store cafés also offer supermarkets an opportunity to flash their green credentials. At Tesco's new Wick store, for instance, there are locally sourced stone counters, energy-efficient coffee machines and toasters. From April, it plans to offer Rainforest Alliance coffee to staff and customers in eco stores such as Wick and Shrewsbury.

Despite all the innovations, coffee remains at the heart of most in-store offers. "Coffee is our 'hero' offer and features in all our café formats - as a minimum we benchmark against the high street coffee chains," says Sainsbury's Hatcher.

Both Sainsbury's and Tesco have hooked up with high street coffee chains. The former has 38 Starbucks units, which are run on a share-of-revenue arrangement, while Tesco has six Costa units, which it runs on a similar basis. Though Tesco intends to open more Costa units in the future, Sainsbury's says it is unlikely to add any more units.

There is clearly some wariness over joint ventures, probably because the supermarkets prefer to take the glory - and the revenue - themselves, although Thrale argues that coffee brands are much stronger than the multiples' and therefore better crowd-pullers. But whether joint ventures or wholly owned, in-store cafés are likely to become increasingly integral to the mix.

"In the next 12 to 18 months there could be widespread upgrades to attract a broader customer base and better serve an older population who are becoming more aspirational, sophisticated and looking for healthy options," says Robert Clark, research director at analyst Retail Knowledge Bank. The days of the £1.99 cooked breakfast could well be numbered.nHow the retailers match up

M&S (main picture) is extending its Eat Over Deli format from four to 40 stores. Its main format, Café Revive, is in 213 stores

Waitrose (above) has upped cafe numbers to 49 in the past three years

Sainsbury's is refitting 85 of its 231 cafes this year. A further 70 refits are planned for each of the following two years

Asda's new-look café (far right) ranges from 1,000-4,000 sq ft. It has so far been rolled out to 49 of its 150 stores with a cafe

Morrisons' cafés vary from 38 to 240 seaters, with the core housing 200