Office brew

A few weeks ago, we welcomed a wonderful new addition to our Edinburgh team; smart, sexy, fun to be around and fully Bluetooth compatible, our shiny new Grainfather brew kit instantly felt like one of the Ferment family.

A few weeks ago, we welcomed a wonderful new addition to our Edinburgh team; smart, sexy, fun to be around and fully Bluetooth compatible, our shiny new Grainfather brew kit instantly felt like one of the Ferment family. But, truth be told, we were also slightly intimidated.

Most of us had dabbled in kitchen counter home brew in the past; ramshackle efforts involving muslin cloths, Ikea stock pots and – more often than not – moderate to serious burns. This three feet of gleaming stainless steel, with its hoses, baskets and digital controls, betokened a level of expertise that we knew in our hearts was a lie.

So there it sat, day after day, with each of us daring one another to order the ingredients for a first brew. Just as the tension threatened to become too great, the deadlock was broken by a kind offer from Edinburgh’s Brew Store, for a day-long course in basic brewing on the Grainfather. Brew Store is part shop, part consultancy, part homebrew community hub, and we leapt on owner Shirley’s kind offer of guidance.

The course was led by the charming and patient Theo, who walked six of us – myself and five other aspiring home brewers from across Scotland – through the fundamentals of recipe building, the brewing process itself, and how to avoid common mistakes.

We began by mashing in, adding bags of our chosen grains to water held at a steady 70 degrees by the Grainfather’s thermostat and powerful heating element. Theo explained the importance of constant stirring as the grain is added, to avoid “dough balls” forming in the mash, and we all dutifully took out turn stirring the thickening malt porridge.

With a press of a button, the Grainfather’s motor whirred into life, pumping liquor (hot water) from the bottom of the mash and spraying it over the top. This is a key feature of the kit; recirculating the liquor through the mash gives the enzymes on the grain husks more opportunity to convert their starchy kernels into useful sugars.

During the hour or so it takes for this process to complete, we learn a little more about the malts being used to create our English pale ale. By far the largest bag is our base pale malt. This yields the lion’s share of the fermentable sugars that will eventually be converted to alcohol. Next up are crystal and caramel malts. We’re invited to taste some of the grains, which burst with a pleasing crunch and release warming, nutty caramel across the tongue. These, we are told, will yield a higher proportion of unfermentable sugars; molecules far too large to be consumed by yeast during fermentation, which will end up giving a rich sweetness.

Our next step is to lift the inner cylinder containing the grain so that it is sitting just over the hot, sweet, malty liquid ‘wort’. We then slowly pour more hot water from a large kettle over the bed of grains. As the water passes through the grain and into the wort below, it washes out the last remnants of sugar, in a process known as sparging.

In the moment we’ve all been waiting for, it’s now time to add our hops and begin the boil. We’re using two different varieties of hop for this brew – Goldings and Fuggles – added at 60 minutes for bittering, then more at 30 and 15 minutes for more subtle hop character. Having cranked up the Grainfather to full power, the 2000-watt heating element soon has our wort at a rolling boil, so in go the hops. 

While we’re waiting (again), it’s time for a chat about the different hop varieties available to us as British brewers, and a rummage through the Brew Store’s well stocked fridge. It’s a fascinating hour, nosing various pellets and whole hop cones, rubbing the oily, fragile, pungent flakes between our fingers and enjoying a whistlestop tour of the myriad flavours and aromas one can extract from these special and unique plants.

The end of the boil also marks the end of the ‘hot side’ process. As everything from this point will be about cooling the liquid down, cleanliness now becomes extremely important. Theo explains that fermentation is about selecting which micro-organisms will colonise the beer over the next couple of weeks; in our case a very standard ale yeast. Anything else introduced to the liquid – on the inside of the fermentation vessel, left on a poorly sanitised thermometer, or clinging to the wall of an unsterilised hose – could reproduce alongside our yeast, creating off flavours or even ruining the entire brew. Theo is scrupulous about cleaning every piece of kit with a special sud-free sanitiser spray and hot water. 

Our object now is to bring the beer down to ‘pitching temperature’ – the temperature at which the yeast can be added. For several reasons, mostly to do with avoiding off-flavours, this must happen very quickly and requires a piece of kit called a cooling coil. The beer is pumped through a coiled hose, which is encased in another wider hose, through which we run cold water from the mains. As the hot beer passes through, it is chilled by the cold water running the other way; the waste water come out hot, while the beer emerges at 16 degrees Celsius, straight into a sanitised fermenting vessel. Lovely.

With the beer at a more reasonable temperature, it’s also time to see how ‘efficiently’ we’ve extracted the sugars from the grain. This is achieved using a device called a hydrometer, which measures the density of the liquid and, by inference, the amount of sugar it contains. In plain old water, the hydrometer (which looks like a thermometer with a bulbous weight at the bottom) will sink to almost its full length, with only a centimetre or so showing above the water line. As the amount of sugar increases, the hydrometer rises.

This is a crucial measurement; by comparing this ‘original gravity’ of the beer before fermentation against another ‘final gravity’ measurement taken after fermentation, we can calculate how much sugar has been converted to alcohol, and therefore give an accurate abv figure.

Since the beer won’t be ready for another couple of weeks, Theo goes full Blue Peter and shares one he made earlier. It’s fascinating to taste how the various raw ingredients we felt, tasted and smelled as they went into the Grainfather have married together to produce an excellent and well balanced beer. It’s a style I’ve probably tasted thousands of times before, but somehow having been manually involved in the process has given each of us a deeper appreciation of the sum.

Back at Ferment towers, I’m anxious to share my new-found knowledge with my colleagues. So, armed with a Brew Store porter recipe pack and a few pieces of kit we’d been missing, I begin Ferment’s very first office brew.

Working as closely as possible to what I’d learned the previous day, most of the process goes to plan. However, as Theo had warned me, every brew is different and there’s no substitute for experience. So, for example, during sparging the water from the kettle passes through my layer of malt very quickly and, as a result, I only manage an efficiency of around 70%, slightly undershooting my target original gravity (which will probably mean a lower abv).

Perhaps more seriously, our (slightly unorthodox) plumbing causes the cooling coil to spring a leak at a crucial moment, meaning my nascent beer goes into the glass fermenter at a ridiculous 60 degrees. Even partially submerging the fermenter in a hastily improvised bin of ice water, cooling takes far longer that it should. I then start thinking about all the moments when I may have accidentally contaminated the brew.

The good news is that, at the time of writing, my first porter is bubbling away in our stationery cupboard. There will be a full critique in the next issue, but in the meantime, the main lesson I have learned is this: even a simple brew is a massively complex equation. There are so many variables involved that it will take years of practice, trial and error to get a feel for the subtle organic forces at work. Taking my first steps on this road, this realisation is as exciting as it is daunting, and I can’t wait to take another go.

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