Brewing with Nuruk - Korean Farmhouse Ale
I am not sure how I first found out about nuruk, but a long story short I became determined to brew up a batch of makgeolli. Having recently moved to within walking distance of Korea Town here in Toronto, I set out to find some nuruk. I eventually found it being sold as enzyme powder with the only additional English in small print on the back indicating it was required for making makgeolli. With nuruk now in hand, step one of my quest was complete.
For those who are unaware, nuruk is a combination of moulds, bacteria, and yeast which is used to ferment the traditional Korean beverage, makgeolli—there are alternative spellings, but makgeolli is perhaps the most common. Similar to kome-koji used in the production of sake, the same process occurs. The moulds present on the nuruk produce alpha-amylase which converts the starches of the rice into simpler fermentable sugars for the yeast and bacteria to consume.
To be honest, I wasn’t too particularly interested in making makgeolli, and more so in harvesting the unique yeasts and bacteria present for the fermentation of a sour beer. Granted the potential presence of food borne pathogens was a bit troubling, but you can rest assured that I survived.
I made a light 7.5ºp “wort” of 2.1kg of sushi rice for 23 litres (assumed based on potential extract of rice - as gravity can not be measured due to the parallel fermentation). In addition to the package of nuruk, I pitched a small starter of dregs of two bottles of Bellwoods Brewery’s No Rest For the Wicked. Which according to the brewer was a combination of Brett, Lacto, Pedio, and Sacc. After primary fermentation, I transferred the makgeolli to secondary, and saved the lees to pitch into a subsequent batch of beer.
Because makgeolli has been traditionally a farmer’s drink, being produced locally across the country side with variation in process and recipe from farmhouse to farmhouse, my natural inspiration was to use the slurry in the other well known farmhouse beverage, saison. From a short googling, there a few breweries who have done a sake/beer hybrids. Goose Island’s Kisetsu, Hitachino Nest’s Red Rice Ale, and Cambridge Brewing’s Banryu Ichi but as far as I can find no one has done a Korean-Belgian hybrid beer. Therefore for the sake of experimentation, I figured it was my duty to brew such a concoction.
Korean-Belgian Farmhouse Ale
15.6ºp (1.064) sg
1ºp (1.004) fg
Canadian Malting 2row 5kg
Canadian Malting Munich 10l 900g
Sushi Rice 750g
28.5g Willamette 4.7%aa 12 ibus 90 minutes
28.5g Mt. Hood 5.6%aa 11 ibus 30 minutes
28.5g Sorachi Ace dry hop 0 ibus 7 days
28.5g Nelson Sauvin dry hop 0 ibus 7 days
CaSO4 .4g per gallon and CaCL2 .4g per gallon added to de-chlorinated Toronto tap water.
- brewed on 170814
- precooked rice, and chilled with water to the same temperature as the main mash @ 65ºc, then combined the two. Mashed combination for 1 hour.
- pitched 1.6 litre slurry of makgeolli lees
- visible signs of fermentation at time of writing