When is a simple recipe not simple? When it is sake. Sake is made from water, rice and yeast. These three simple ingredients begin an incredibly complex process that extends beyond my brewing knowledge, but here goes…
Sake production begins with specially selected sake rice that is polished to remove the bran and leave behind a pearly white grain. The degree to which the rice is polished is generally a sign of differing qualities of sake. Sake labels refer to this quality in terms of percentage with, for example, 40% (meaning 60% of the bran has been removed,) being of a higher quality than 60% (40% of the bran has been removed.) The rice is then rinsed thoroughly before being steamed to cook it.
The next step is where the magic begins: the koji is added. Koji is a mould that begins to convert the rice starches into sugars (much like a maltster does to barley for brewers.) As the koji works it’s spell, the rice is watched over and cared for like a newborn baby for 36 hours. When the process is done, a white coating is visible on the outside of the grains and this is where the delicate, fruity aromatics of sake start to form.
This koji rice is then added at a rate of around 15% to a tank with water, more steamed, polished rice and a blend of yeast. This slurry is agitated regularly to keep the rice in suspension and mix in a little oxygen. Sake fermentation relatively long compared to beer, usually lasting between a month or two (usually beer ferments in 1-2 weeks.) The slurry is then pressed to separate the sake and the lees (yeast and rice sludge). The lees is used for many things such as a vegetable pickling agent, cosmetics ingredient and can even be re-fermented into a super-dooper umami paste (sake vegemite, anyone?) From here the sake can be filtered before being bottled or left unfiltered. It can be bottle conditioned to give a little spritz or not.
Though I wouldn’t claim to know everything about sake, what I do know is that it is an ancient tradition that follows many traditional methods that are passed down from generation to generation. Most producers that I came across are in at least the fifth generation of the family business. From master to apprentice, the secrets passed down tell a story of precision in temperature, proportion, water chemistry, rice varieties, yeast blends and the all-important koji. These specific combinations yield a range of different sakes from those that are deep, savoury and earthy to sakes that are light, bright and full of fruity esters.
Quintessentially Japanese, sake is an amazing drink with a long history that has once again shown me that simplicity and attention to detail can yield the finest of products.