"Ask Beau" September 2005
If you were using metal cups I would say a big no! Honestly, the microwave is used in restaurants across this nation and you wouldn't be able to tell the difference. But I recommend using a pan of boiling water. A gentle heating rather than a nuking allows the alcohol to change slower, which I believe gives off a better flavor. In this regard, I say grab a "Tokkuri" (a slender tapered vessel that has a chimney top – you have seen these at any Japanese restaurant usually in white ceramic form) and fill it with a good heating sake.
What is a good heating sake? Well there are several and they do taste much better than table sakes in a warmed state. (Fukunishiki, Nishinoseki, Kamoizumi, Masumi are four names of excellent heating sakes to choose from at True Sake) Then fill a pan half way and bring the water to a boil. Put the Tokkuri in the pan and turn the flame or heat off. Do not touch the sides of the Tokkuri to get the temperature of the sake on the inside, rather lift it out of the water by the top and touch the indented bottom. This concave area creates an air pocket that is not influenced by the boiling water; rather it gives you the temperature of the contents on the inside. Americans have the propensity to overheat sake, but as long as you like it flaming that's all that really matters. I feel a temperature of about 120F is perfect for hot sake "Atsu-kan" and around 90F for "Nuru-kan" which is lightly warmed sake.
Please send your sake specific questions to askbeau2 @ truesake.com. (This address is not for general questions and I only review the questions once per month. All correspondence should use info @ truesake.com.)com"> firstname.lastname@example.org.)