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Slot Machine

Many café owners are excited by the possibility of being in control of the coffee-making process from bean to cup, taking full ownership of what is served to customers while extending their own knowledge and feel for the drinks they serve. Notes, Mission Coffee Works and Vagabond are just some of the cafés that have made the jump to roasting on their own machines.

White-label (or toll) roasting is a widespread and popular way of bringing distinct blends to cafés. Roasters such as Has Bean began the move towards white-label coffee by producing bespoke blends for cafés while retaining Has Bean’s own brand on the packaging: the café gets a unique coffee but the identity of a respected and established roaster. White-label takes this one step further: the roaster provides a tailored roast to a café but the café is allowed to brand the packaging and, effectively, the coffee’s profile as its own. Modern Standard, which roasts for this issue’s featured café Relax, also roasts white-label coffee for many others. It’s a significant part of many roasters’ business.

Slot-roasting is subtly different. A café buys unroasted beans, sometimes in collaboration with one or two other buyers to reduce shipping costs, and is then allocated a ‘slot’ at an established roaster during which it can roast its own coffee.

Hands-on experience

Coffee has always been an innovative industry, with information on new practices often willingly shared face-to-face through blogs and at coffee events. But until recently, getting the kind of hands-on experience needed to gain even the most basic understanding of roasting – a complex process that people spend their lives perfecting – has been hard to come by. In the US, roasters such as Highwire Coffee in Oakland have pioneered ‘tenant’ roasting schemes. In London, however, the premium on space and equipment has meant such opportunities were limited until the recent growth in smaller roasteries.

Gavin Fernback, who runs artisan café The Fields Beneath in Kentish Town, is a pioneer in the London slot-roasting movement. He started buying coffee from Tate and discussed the possibilities of slot-roasting with Tate’s former head of coffee Ben Prestland. Ben’s successor, Phil Gervaux, was also interested in educating more people about roasting and making the idea of slot-roasting a reality, so Gavin shifted all his espresso buying there “so we could spend more time with them, do more cuppings and just hang out.”

Gavin is very excited about the opportunities to roast for The Fields Beneath. “We have more control, produce our own bags of coffee and it’s something new to learn,” he says. “It also means more Instagram pictures!”

Rob Hurst and Pete Duggan of Full Stop on Brick Lane are also making use of Tate’s facilities and agree about the opportunities it affords. “We get to learn new skills and more about the processes coffee goes through before it arrives at the coffee shop,” they say. Both cafés see that slot-roasting makes business sense too because it reduces costs, which can make a huge difference for small cafés in a hugely competitive sector.

Consumer benefits

Tom Haigh, head of green coffee at Climpson & Sons, recognises the business potential of slot-roasting from the roaster’s side. “Roasters who have less coffee quantities to think about and periods of time when the roaster is sat idle would consider slot-roasting a good opportunity to make up the margins on production costs as well as educate a few knowledge-thirsty people in the industry,” he says.

Gavin is also keen to advocate the potential benefits for consumers. Any good café has a relationship with its core customer base, people who come in regularly and enjoy watching a café grow and develop. “Our customers like it when they can support us in this venture, and it’s something different for them. Good coffee is good coffee, but we can now have coffees roasted with a profile, and in bags, they can’t get anywhere else.” And this sense of uniqueness is likely to remain. “We aren’t looking to wholesale, at least not for espresso,” says Gavin.

Pete and Rob from Full Stop also see individuality as a key benefit:

“We get to taste lots of different coffees and choose which ones we want to use and how they are roasted.”

And while Gavin does admit that customers won’t experience quite the same variety as they once did as The Fields Beneath will no longer be changing roasters, they will be getting a brew they can’t find anywhere else. This is an exciting development for any café and, hopefully, one that customers will appreciate.

Potential pitfalls

Roasting is a tough game. Rob and Pete recognise that they’ll have to bear the cost if a batch goes wrong, which could be costly for a small business. Gavin also admits that roasting is a daunting learning process, although he sees that as an invigorating challenge and accepts that occasionally getting things wrong is all part of getting better.

Working to someone else’s schedule around roasting slots can also present some logistical difficulties, but Gavin sees that as being off-set by the potential collaborations that slot-roasting brings.

Tom from Climpson & Sons can also see the potential pitfalls for roasting neophytes. Climpson & Sons began with a market stall and café around 13 years ago, serving another roaster’s coffee. It bought its first roaster, a 3kg machine, in 2005 and now works a 35K Loring. Around 10% of its business is roasting bespoke blends for other customers; the rest is sold under its own name and served in the company’s café, so it has experience of all sides of the roasting business.

Tom believes the biggest single challenge for slot-roasters is acquisition of knowledge: “I’d think slot-roasting could be pretty rudimentary, as it takes a long time to get to know the roaster machinery and the coffee, and apply the correct techniques,” he says. Sourcing green coffee is a full-time job in itself, as are the logistics around importation and forecasting how much coffee will be needed. All this varies by country and from year to year as harvests change. For slot-roasters, much will depend on whether they get someone else to do this job for them or – as Gavin does – go into partnerships on the sourcing front.

The next hurdle is the application of roasting profiles, which has to take into account the origins of the coffee, its processing, the varietals and so on. All this knowledge is necessary in order to work out the density and moisture levels of the green coffee to roast it correctly, and experimentation and constant tasting are key. Once roasted, the coffees are analysed further. “We use the cupping table as a basis for this, tasting every single roast and scoring the flavour for each coffee,” says Tom. “We then analyse our solubility and chemical development using refractometers and TDS readers to ensure we’re hitting the mark.”

And all that is before you even consider the fact that each roasting machine seems to have its own quirks that need to be discovered and learned. According to Tom, using a coffee roaster for the first time is “a bit like trying to use the shower in someone else’s house, experimenting to get the perfect water temperature. If you jump straight in, you just get scalded.”

Bright future

In short, getting roasting right is a tall order, one made taller still when the machine is not yours and it’s not your full-time occupation. Nonetheless, Tom sees a bright future for slot-roasting. “It’s an increasing trend. Thanks to the amount of new roasteries and cafés out there, coffee shops are going the extra mile to set themselves apart from the herd, and developing their own brands and roasting labels is a great way to do this.”

The coffee world is known for its inventiveness, and café owners such as Gavin Fernback see these issues as exciting challenges to overcome rather than daunting obstacles. Ultimately, the customer will be the beneficiary, as the variety of available coffees expands. Every coffee drinker has something of the adventurer in them, searching out new places to visit and new roasts to try in different forms, and anything that adds to the market in that way has to be an exciting development. Of course, the cafés taking part in this revolution will encounter some issues, but the thirst for greater coffee knowledge and a desire to keep pushing the industry into new and exciting areas are things every coffee drinker should welcome.