Have you ever thought about how your soy sauce is made, or what makes a soy sauce a good soy sauce? I didn’t until I interpeted for a tour at the local luxury soy sauce brewery that produces the soy sauce used at the local luxury inns.
The Hirano Syouyu-ya is located on a street in Matsue with many other old family owned businesses built in the early Showa (post-war) period, where the business store front faces the street and the home is behind it. We started the tour with Hirano-san pointing out some other businesses on the street, and then inviting everyone into his home to see his classic Japanese style living room and garden (a surprising number of people can fit in a narrow space). After that, we went down the alley to the factory entrance behind the house.
Soy sauce starts as a fermentation of soy beans, wheat, and yeast in a brine. After it has thickened up for a few years, it becomes a thick slop called moromi. While he cautioned everyone not to fall in, Hirano-san invited us to taste it.
After the moromi has matured, it gets pressurized to squeeze the liquid out of it. The liquid goes on to become the base for soy sauce. The solids remaining are later used as fertilizer, and they sell vegetables grown with it.
It takes a little more time to mature, and then it becomes the soy sauce we all know and love.
But if the process stopped there, it wouldn’t be luxury soy sauce, now would it? Part of the fresh soy sauce brew gets used as regular soy sauce or gets mixed with different flavors (they do a lot of experimentation with different items, usually other fine seasoners in Japanese cuisine). The rest of it, however, gets put back where it came from to serve as the brine for a new brew of moromi. This results in a much thicker sauce, which is not as salty as the single-brewed sauce. When you take away from of the saltiness, you can detect a much deeper flavor profile. While I am not a soy sauce expert, I noticed a big difference between the single-brewed soy sauce and the twice-brewed soy sauce. Indeed, the twice-brewed sauce is much nicer!
For anyone who would like to know more (and doesn’t mind it being in Japanese), please take a look at the Hirano homepage.
Finally, Hirano-san (a fourth generation brewer with a thick Izumo accent) wanted me to tell everyone a little more about him after the tour had ended (and after he and his wife were nice enough to give us all seasoned sesame seeds–which I love!):
This isn’t to say he brewed the sake himself (though he could with that equipment!), but that he could distinquish which kinds of sake he was tasting. What a cultured tongue he has! He has a taste for jokes too, so it was fun to interpret for him.