Miso!

Why talk about miso?

Because it rules! This will also make more sense in the next blog post. For now, let’s dive into (or rather snorkel through) miso fermentation, what makes it so cool, and why it tastes delicious. I won’t go in depth, but you can still get a reasonable idea of miso production and use from this overview.

Miso fermentation is a traditional Japanese method that transforms soybeans (traditionally), rice or barley, salt, and koji (a type of moldy rice) into a flavorful and versatile paste. The process involves mixing the ingredients and allowing them to ferment for weeks, months, or even years, depending on the desired flavor profile. During fermentation, koji enzymes (namely proteases and amylases) break down the proteins and carbohydrates in the ingredients, creating a rich and complex umami taste. The longer the fermentation, the more complex the flavor, generally speaking of course. The salt added at the beginning keeps everything stable while it ferments, and the end product is sort of doubly stabilized by the salt concentration and fermentation byproducts such as acids that lower the pH of the miso. The breakdown of proteins into amino acids, however, is the real key to miso’s success.

So, what exactly is koji? Scientifically speaking, koji is cooked rice that has been inoculated with the mold Aspergillus oryzae. While the mold is present in miso during fermentation, the way it works is more nuanced. It’s actually not so much about the mold, as it is the enzymes the mold produces. Miso is preserved with salt, which actually kills the Asperggilius oryzae leaving just the enzymes behind. Koji's enzymatic action is so crucial that it influences the overall quality and profile of miso, showcasing the significance of this mold in Japanese culinary traditions and beyond. Koji is not the end of the story, however. Lactobacillus and other salt tolerant bacteria and yeasts (often called halophiles) are also invited to the party. These produce different flavor compounds and acids which contribute to miso’s overall complexity.

So, why even bother going through all of the trouble to understand miso, or potentially make it yourself? Because understanding how food operates will make you better equipped to extract the most potential from each ingredient. You also have to admit, it’s pretty cool, right? So now that we know that koji enzymes break down proteins and starch, we’ll look at what that does to the flavor. Amylase breaks starches down into sugars. This is pretty straight forward. As you can imagine, your tongue will now perceive the miso as slightly sweet. Protease breaks the proteins down into amino acids. These little buggers are not only the building blocks of life, but also pack the flavor of umami (aka savoriness); the fifth taste. There is, however, one very special amino acid that rises to the top, and becomes the mayor of flavortown. This amino acid is glutamate. And you see, when a glutamate meets sodium (remember that salt used to preserve miso?) they fall in love. They do the dirty and become a sensational pair called monosodium glutamate. Yes, the same MSG that everyone told our parents to be afraid off. You know what that is? Gobbledygook, that’s what. Maybe I’ll do a whole other post on MSG one day.

Miso is an incredible product because it offers unique flavor and intensity to anything it touches. Miso soup; gotta love it. Miso glazed fish; delicious. Miso mayo; bada-bing bada-boom. All this talk is making miso hungry. Sorry, I couldn’t help myself. So, the next time you're making anything that you want to add a savory edge to, try replacing a little bit of the salt with miso. You can use soy sauce in a similar fashion. In fact, next time you make a stir fry, try seasoning with miso, soy sauce, and salt combined to take it to the next level.