First let’s cut to the chase. Heating sake is good! When you have had bad hot sake it wasn’t the fact that hot sake is bad it’s that bad sake makes for bad hot sake. Most of the sakes that get heated in the US are made in the US. I am not saying that all domestically made sakes are inferior, they aren’t. I will say that a lot of box sake that they put on those heating machines is not the best, and you can taste it. In a word, there are really good sakes for heating, because most Japanese sake drinkers enjoy a tasty warmed sake, especially when it is cold out.
Why warm a sake? There are a lot of reasons. Warm sake warms you up and takes the chill off. Warm sake goes well with warm foods. Warm sake is fun to drink in that you get to fill up your little cup and that of your companions. Warm sake gets you buzzed a little quicker. (This is a perceived notion that may or may not be true.) And it’s possible to extend a sake’s shelf life by heating it when it has gone a little long in the tooth. But most importantly warm sake makes the sake taste differently. By warming a sake you are actually creating more flavor and feeling points. The heating actually brings out deeper or more reflective flavors that you do not discover at chilled temperatures. Warming sake is like opening a door to second larger room than the one your standing in.
Seven years ago I was at an amazing izakaya in the heart of sake brewing country in Kobe Japan. The sake-centric restaurant was designed so that you were looking down on the sake master who was tending both food and sake services. He had three separate waters heaters lined up side by side. Each heater, which resembled a hot water bath or small chaffing dish filled half way, was set at a different temperature. The sensei was overtly curious about my sake fascination so he started a small educational course for me. He started by pouring me a sake from three different warming vessels in the same bath. I tasted all three. They were pretty damn good and they were all different in flavor and feeling. I told him they were all good and I preferred the middle cup. He grinned and said that they were all the same sake. Really?
The first lesson by the sensei was that each of the warming vessels was made with a different metal – pewter, steel and copper. Each of the metals heats at a different rate. Steel is fast. Copper is slow. Pewter was in between. The cup that I liked a little more than the others was the pewter vessel, so what I learned was that the pace of heating sake can have a real effect on the end product. If you warm sake too quickly it does one thing, if you warm it too slowly it does something else. The trick is to see at what pace heating your sake is the best for flavor.
There are many ways to heat sake. The sake heating machine for one. The microwave. The pot filled half way with boiling water. Heck I have even used a hotel room coffee machine. I have also had a tokkuri (ceramic chimney shaped heating vessel seen at every Japanese restaurant around) precariously balanced on a burning log at a beach bonfire. Two of my favorite heating stories involve toji or head sake brewers who had two unique ways of warming their brews, one more “olden days” than the other.
The first guy told me that at their brewery as they finished brewing for the day, the youngest guy is charged with the job of pouring sake into a tea kettle and putting it on a little burner. Didn’t this damage the sake? No way said the toji and this took away the perception that sake needs to be perfectly warmed. The second method by the other much older toji was really old school. He said back in the day guys would sit around and drink sake that they had warmed in their own crotches. Yup just like when at hockey practice your hands are so cold that it feels warm and good to stick your hands down your pants the same principal holds for warming sake to 98 degrees. I asked if you would pour for other guys with your own tokkuri and he laughed and said, “I can’t remember.”
So tea kettles and crotches aside what way do I recommend heating sake? I prefer the boiling water bath. For this you need a pan, water, tokkuri, and if you have a sake thermometer great. The tokkuri is a unique vessel in that it has a concaved bottom, which is used to feel the temperature of the sake in the vessel as opposed to touching the sides of the tokkuri, which gives you the water temperature. An air bubble keeps the hot water out of the pocket and gives you the temperature of the sake within.
Bring the water to a boil and place the tokkuri in the bath then turn off the flame or the heat. Usually the sake will warm within two to four minutes, unless the sake was chilled in which case I leave the flame on for an extra minute. If you don’t have a tokkuri then use a 300ml sake bottle or “dinky” wine bottle, just be sure to take off the cap. If you are lightly warming the sake then I pre-heat my sake cups (o’choko) in the sink with running warm water. Some sakes do much better lightly warmed as opposed to lava hot, but it is entirely up to you.
If you are in a bind – use the microwave! The sake heating police will never find you. But I find that the quick burn zaps the booze of the brew and makes the sake taste more zesty. Again, there is no perfectly warmed sake. It’s more of a time, place and story effect. So go make your own sake warming story!