Mozart most likely never tasted Saké but that doesn't mean he cannot help produce a better Saké.
Last month, I mentioned how a Sherry bodega was playing music to help the flor in their barrels. Though some wineries play music in the vineyards, a few of them play music in their cellars, allegedly helping the wine as it ages. There is a Saké brewery that is doing something similar, though the music is not played in the rice fields or while the Saké ages. Instead, it is played during the fermentation process.
There is a new article in the Toronto Star, Japan turns to Mozart to improve sake taste, which discusses the efforts of the Ohara Shuzo, a brewery in the Fukushima Prefecture. For about twenty years, the brewery has been playing music for the fermentation mixture during the third stage of the brewing process. For two hours a day, they now play Mozart, having previously tested other music such as jazz, Beethoven and Bach. They found Mozart worked best for them though.
Japan Times Online also discussed this practice, noting that Mozart is used by others too, including a fruit company on their bananas.