Zero Waste Natto? DIY!

I want to share how I have made natto at home.
Basically, I have followed the steps from Emmy in Japan's DIY Natto in an Instant Pot video as well as following along with Natto Dad's advice on his blog.
The main difference between my recipe and theirs is how I cover the natto while fermenting. Their method consists of two layers of cling-wrap with holes pricked using a toothpick. I don't own cling-wrap. What I have done instead is use a combination of parchment paper and aluminum foil.

While the natto ferments, there is a layer of cling-wrap that is pressed up to the surface of the beans. For this layer, I used parchment paper. I chose parchment paper for this layer because I didn't want the metal touching the beans. I am not sure, but somehow I worry that it could interfere with the flavour (this is totally unfounded). For the top layer, I use aluminum foil. I also add a rubber band to make sure everything is secure.

I also use a sanitized pin/needle to poke the holes in the two coverings instead of a toothpick.

Parchment paper can be composted. Aluminum foil can be recycled. I suppose you could try to reuse the aluminum foil, but it would require sanitation. The rubber band and pin are of course both reusable.

Basically, all I am writing here is that the plastic wrap can be replaced with reusable, recyclable and compostable materials!

Unfortunately, there's a part of this process that isn't zero waste, because you need to start with something. I've started with store bought natto that comes in styrofoam. Since the natto from the store is cut into 9 pieces, we are still getting a whole lot of natto per styrofoam package in comparison to just buying from the store and not making it at home. I think if I make a particularly good batch in the future, I will preserve some of that natto and see if I can propagate from that instead of using store bought.

I also suggest looking for soybeans at bulk stores that allow you to bring your own containers. I bring a mesh bag into Bulk Barn and am able to buy a large amount of soybeans for a very low cost. Hopefully, this post can help someone who isn't sure about making the process a little bit more environmentally friendly.