Exploring the Ambiguity of Coshi in Sake Classification

This week we’re digging a classic from out of the cellar – our episode exploring the absolute magic of sake that’s been crafted to stand the test of time.While still a relatively niche category within sake, more and more producers are leaning into clearly communicating the amount of time – and in what form – their sake spends maturing prior to release, and the wider beverage-loving community is finally taking notice.From a production standpoint, there are tricks of the trade that allow for all variety of flavor and style creation. The one quality that really can’t be replicated, however, is the unique and special character born only through the passage of time.We welcome you to take a step back in time with us this week, joining your hosts Marie Nagata, Sebastien Lemoine, and Justin Potts, revisiting this episode originally released back in the spring of 2021. If you’re looking to further explore the world of aged sake, I encourage you to check out the special session we hosted on the topic for the Sake Future Summit back in 2020, as well.Thanks for tuning in this week. We’ll be back with more Sake On Air for you very soon. Despite a rich and storied history spanning millennia, in certain terms, sake has yet to unequivocally prove its ability to stand the test of time.If you’re in some way associated with the sale or service of sake, likely one of the most common questions you get is, “How long can I keep my sake before it starts to go bad?” or, “How long does sake stay good after it’s opened?” As a buyer, these are both logical and very important questions. As an industry, having clear and concise answers to those questions is equally important. In order to keep things simple, as well as to help assure an overwhelmingly positive experience for as many sake drinkers as possible, the general message adopted suggests that sake should be consumed within 6-12 months from purchase, refrigerated both prior to and after opening, and then consumed within several days to a week once it’s been opened. This is sound advice that’s relevant to a great majority of the sake being produced and sold both domestically and internationally.There is, however, a paradigm that exists entirely outside of the above logic; where a greater element of time isn’t only a factor, but a necessity.Welcome to the world of matured and aged sake.Often referred to as koshu – literally “old sake” – often translated as “aged sake”, or jukuseishu, commonly translated as “matured sake”, bottles of sake referencing these qualities were crafted taking time into account. That amount of time can be anywhere from a few years to a few decades depending on the style of sake and the intent of the brewer, and in many cases the results are astounding.Yet despite plenty of beautiful examples of aged or matured sake on the market and countless historical texts singing the praises of what time can do to a bottle of sake, a rather perfect storm of circumstances coalesced to nearly erase aged sake culture, production, and consumer appreciation from the collective understanding of sake for about a century.Thankfully, a relatively small, but thoughtful, proactive and coordinated effort from a growing number of sake makers and sellers has been hard at work seeking to rebuild and redefine what time can mean (and cost) when factored into a bottle of sake. Whether it be the collective rebranding efforts of the Toki Sake Association, the Muni line from Kokuryu used in the first ever sake industry auction in 2018, the dedication to long-term aging in ceramic storage vessels by Tsuki no Katsura, or a handful of specialty bars dedicated to the unique and treasured style, awareness surrounding the magic that time can work on a bottle of the right kind of sake is slowly building.This week, Sebastien Lemoine, Marie Nagata and Justin Potts gather to discuss the historical and modern context of matured and aged sake, the formal definitions (or lack thereof) in place,