white belt wrote: ↑Thu Aug 12, 2021 8:51 pm
I would like a bit more fuzziness, so I'm experimenting with letting one of the bags ferment for another 12 hours. The first bag I fried up with some seasoning and will be using it as ground beef replacement in my lunches this week. I will report back with how the fermentation develops on the 2nd bag.
The extra 12 hours of fermentation just led to some more graying/blackening, so I think I'll just stick to a ~24 hour fermentation period for my region during summer months. I'll report back on how that fermentation time changes through different seasons (I'm expecting winter months to require 36-48+ hour fermentation).
I made another batch of tempeh, this time in bulk and I think I've got my process down enough to publish here. I started with 2 lbs of raw soybeans since that's the maximum that will fit in my 6 quart instapot, but scale up or down as you see fit:
Ingredients
-2 lbs raw soybeans*
-1/4 cup apple cider vinegar
-2 tsp tempeh starter (see earlier post about recommended brands)
Equipment
-Instapot (or any method to cook soybeans)
-baking dish (I find this to be superior to the plastic bag method in just about every way)
-aluminum foil
-skewer
Instructions
1. Rinse the beans off in a strainer and look for any rocks or foreign substances. This will start the process of washing off some of the antinutrients.
2. Soak the beans in a large bowl with ~2x as much water as beans. The beans will absorb the water and expand to double size, so you may want to occasionally re-check that you still have sufficient water to keep the beans submerged. Allow to soak overnight or up to 24 hours at room temperature. You will likely see bubbles form at the top.
3. Repeat step 1 when you are ready to cook the beans. If any of the beans have dehulled while soaking then I just throw the hulls in along with the beans.
4. Place the strained and rinsed beans in the instapot (or following typical soybean cooking instructions if you're using a different method). Add the vinegar and 8 cups of water to cover the beans. The acidic environment will limit other organisms from growing while facilitating the growth of the starter.
5. Pressure cook the beans for 18 minutes or whatever your instapot recommends. Wait for all of the pressure to naturally release, which will take awhile with the quantity of beans. I think the entire instapot process took 1-2 hours but I didn't really time it.
6. Once all of the pressure has naturally released, remove the lid and drain all of the liquid from the soybeans. Return the soybeans back to the instapot bowl and return the bowl to inside the instapot.
7. Saute the beans on low heat while stirring them frequently. The point here is to remove some of the excess moisture. You don't want to completely dry out or burn the beans, but you do want to ensure there still isn't liquid at the bottom. Frequent stirring will prevent the beans on the bottom from cooking more or burning.
8. Once excess moisture is removed, remove the bowl from the instapot and place on a surface to cool. If you're feeling impatient, you can place it in an ice water bath like you would for yogurt. Continue to stir the beans occasionally to allow the beans to release steam and cool faster.
9. Keep occasionally stirring the beans until they cool to 110F (or eyeing the beans until you see that they have mostly stopped steaming). Add the tempeh starter and stir to ensure all of the beans are coated in the powder.
10. Spread the tempeh evenly into a baking dish. Aim for 1/2-3/4 inch thickness which will ensure the tempeh on the bottom doesn't go anaerobic. You should pack it down a little bit with your hands or a spoon because that will enable the starter to innoculate the entire block more quickly.
11. Cover the dish with aluminum foil. Use the skewer to poke small holes approximately an inch apart in the foil. This will enable air flow while also limiting moisture loss so your tempeh doesn't dry out.
12. Place the dishes in a warm area and allow to ferment for 24-48 hours (depends a lot on the temperature of the space and other variables). You'll know the starter has inoculated the block when the dish feels warm to the touch after at least 12 hours. You can also visually check that there is a mat of mold on the top like in the pictures below. From there, you can decide on how fuzzy you want your tempeh. If you don't want black or gray spots to form (still safe to eat but definitely less visually appealing), err on the side of shorter fermentation times.
13. To harvest the tempeh, run a butter knife around the edge of the dish to separate the tempeh from dish. You can then cut the blocks into smaller pieces as required. They can store in the fridge for up to 2 weeks or store in the freezer for months.
You will need to cook the tempeh again prior to final consumption. There are countless tempeh recipes on the internet because it's a popular meat substitute for vegans. Tempeh can absorb a lot of moisture, so I highly recommend marinades. On it's own tempeh has a bland nutty flavor, similar to soybeans.
* = You can also make tempeh with other legumes or pulses like lentils, black beans, etc but I only have experience with soybeans
And now some pics from my most recent batch. I started with 2 lbs of raw soybeans and it yielded about 2kg of tempeh, so this should give you an idea of how much tempeh you will end up with if you follow my instructions. I know I'm mixing units of measurement but it makes sense to me since I buy the raw soybeans by the pound but track my food by the gram. This quantity should last me 2 workweek's worth of lunches eating about 150 grams per day of tempeh. I plan on eating a lot of tempeh due to my high protein diet, but with more typical consumption patterns that quantity of tempeh will go a lot further.
I should be able to get a couple of uses out of the foil sheets if I'm careful to not rip them. Longer term I will likely cut up some sturdier foil containers like those used for catering events so that I can have a durable lid that can be re-used indefinitely. I might even scale up my tempeh production to use my roommate's instapot at the same time, so that I can make a month's worth of tempeh in one go.
I'll post some recipes once I test them.