Making Meju Blocks

Three important things in Korean cooking use Meju as a base:
Gochujang - fermented chili paste
Doenjang - fermented bean paste
Kanjang - soy sauce
I am making Kanjang this time. Meju is the basis of Korean cooking and is first attested in a Chinese book from the Han dynasty about the Koryeo kingdom's foods. There are several types of Meju:
1, just soy beans (the most common for most uses)
2, mixed soy beans and malt (I am using this one this time as an experiment)
3, wheat or barley (very uncommon)
Additionally, there are many shapes of it that vary by region and preference. I tried to make the round type and it kept falling apart. So I pressed the meju into bricks using a paper log maker. The brick shape is the most common and maximizes surface area. Meju is a way to preserve soybeans by drying them for later use. Beans are cooked and mashed and formed into bricks and dried until firm, then hung to dry with straw ropes. The straw ropes are very important because they contain Aspergillus molds (usually A. sojae, A. oryzae, or A. niger) and Bacillus subtillus bacteria. These microbes are responsible for the fermentation of the Meju. As they are hung in the straw ropes, they both ferment and slowly dry out. When thry are completely dry and very light weight, then you either grind them for making gochujang, or add them to a brine of 4 parts water 1 part sea salt, and soak for 2 months to several years, resulting in doenjang and kanjang. Longer soaking and aging results in stronger and greater depth of flavor. Soy sauce in Korea is graded by its age and weather or not it contains malt.

Ryan, are you inoculating this? Or is this inoculated by airborne spores?

Tj Jefferson wrote:Ryan, are you inoculating this? Or is this inoculated by airborne spores?

Airborne spores and the straw. I said so in the middle of the second paragraph.

The straw ropes are very important because they contain Aspergillus molds (usually A. sojae, A. oryzae, or A. niger) and Bacillus subtillus bacteria. These microbes are responsible for the fermentation of the Meju. As they are hung in the straw ropes, they both ferment and slowly dry out.

I didn't see the ropes in the pictures. I thought there was a way of maybe doing it without.

I grow both austrian winterpeas and cowpeas (depending on the season), and haven't really come up with a great way to use them other than fodder. The idea of fermenting them is alluring.

I have several crocks, the issue has been the inner lid. I would like something nonporous, and I'm thinking marble (which I can get slab remnants from a nearby place for free). This means some time on a wet saw. Have you found a good inner cover material?

Update on the meju, my whole house smells like Bacillus subtillis bacteria exudate. Luckily, it appears to be the local variety of B. subtillis and not the East Asian B. subtillis var. natto (the exudate of which is ropey snot). Nevertheless, it still has a strange odor that I will be happy to part company with in a few days when the meju are firm enough to hang up in the garage. B. subtillis are absolutely necesary for production of meju along with a fungus of the Aspergillus genus. The two microbes form a compound from soy proteins that is responsible for the dark color and umami flavor of things made of meju.

Tj Jefferson wrote:I didn't see the ropes in the pictures. I thought there was a way of maybe doing it without.

I grow both austrian winterpeas and cowpeas (depending on the season), and haven't really come up with a great way to use them other than fodder. The idea of fermenting them is alluring.

I have several crocks, the issue has been the inner lid. I would like something nonporous, and I'm thinking marble (which I can get slab remnants from a nearby place for free). This means some time on a wet saw. Have you found a good inner cover material?

I haven't gotten to the rope stage yet, so I can't take pictures of it. I don't know what you need two lids for. Korean ferments typically are made in vessels without seals and the vessels are opened on sunny days. It is nothing like making pickles the European way. Kimchi is weighted down sometimes, but when brining meju to make doenjang snd kanjang, the container is never sealed, it needs air to ferment.

Korean ferments typically are made in vessels without seals and the vessels are opened on sunny days.

Now I am really interested. The only issue with Asian ferments is the stomach and esophageal cancer, but given their native life expectancy, it seems to make it up for it in other places in aggregate. I'm going to have to see about this. Thanks for the prod!

Tj Jefferson wrote:

Korean ferments typically are made in vessels without seals and the vessels are opened on sunny days.

Now I am really interested. The only issue with Asian ferments is the stomach and esophageal cancer, but given their native life expectancy, it seems to make it up for it in other places in aggregate. I'm going to have to see about this. Thanks for the prod!

Supposedly, regular consumption of Korean ferments is responsible for the low contraction rates of SARS and avian flu in South Korea.