Koji Spores

Using Aspergillus oryzae and other Aspergillus spores for sake, misos, shoyu, fish sauces, meat sauces, etc.

The next 12 posts will be about specific enzymes, making koji on different substrates such as rice, beans, and other grains like barlet or wheat, research into clinical uses for koji enzymes, the ongoing and widespread use of Aspergillus spp. enzymes (esp. kojic acid from Aspergillus oryzae) in food processing, etc. The amount of information available is voluminous (for those that still read books) and even online. 

Aspergillus sojae grown on black soybeans for douchi, miso and kecap manis

All posts will be in the context of side bars to recipes for tasty food, however.

Any site that sells spores will have descriptions in English, some so incredibly poorly translated you will easily lose patience. What spores yoiu need is really based on the very basic principle that when inoculated at the lower end of the temp range of 85F spores will pretty much produce more proteases and lipases. That a pretty good temperature to aim for if you are making koji on most substrates.

At the higher temperature range of around 104F you will generally produce more amylases. In low or non fat substances like rice for sweet or quick misos, sake, or amasake you want as much amylase as you can get. There are thousands of different spores however, although you’ll probably never be offered more than 50 from any one producer. Spores are designated by how quickly they create heat, or the length of the hyphae.

If you have a bean or a more fat and protein containing substance like barley or meat or fish you really want to be using Aspergillus sojae that is way more inclined to produce proteases, cellulases and pectinases. Most soybean miso or shoyu spores, although rarely labeled as such, are actually A.sojae.

Every spore distributor in the USA always says they only sell A. oryzae, although their spores are always made in Japan. You could create a decent koji from mild rice or barley miso specific spores sold by Gem spores that are A. oryzae to get the job done, but studies clearly show you are not going to get as much proteases etc. to create more amino acids and other things to increase both umami and maximum nutritional value, and break down proteins and fats.

Places like http://www.higuchi-m.co.jp/english/index.html and Akita Konno sell spores http://www.akita-konno.co.jp/en/seihin/index.html through different exporters (a customs certified agent is required). The former provides some really useful charts on what each spore type does, and are the only place we know of that sells the enzymes we use.

Although somewhat difficult to understand these two do the best job of explaining what they are selling. If you are willing to wait a little, and have somewhat that can translate their English translations into English there is always kawashima-ya (https://kawashima-ya.jp) and other sites.

Just remember there are miso spores, and sake spores, and shoyu spores and shochu spores. We have our own spore guy that gets us what we want, but most people will never need what is not offered through the internet.
You can also easily get koji spores almost overnight in the US through the Modernist Pantry (https://www.modernistpantry.com/shiragiku-koji.html -shirayuri is for white things that are sweet, shiragiku for brown things like browner misos and shoyu) 

Most spore providers will provide an English language label, like these spores from Gem Cultures packages available to professionals. They also sell much smaller sizes. These are good spores, but you won’t get the best effect if you use them for beans or high protein sauces or misos.