I will admit that tempeh scared me. The idea of letting soybeans grow mold was one step further than my usual level of fermentation. It was a ferment that I had been blissfully ignoring… until someone arrived on my doorstep with a package of mold and a piece of advice about how to save the spores.
So I took courage… and read everything I could on how to make tempeh… then I made my first attempt. The results were surprisingly – amazingly – incredibly delicious. I had become a master of the mold!
The flavour of homemade tempeh is completely different from store-bought tempeh. It is nutty and creamy, more like eating edamame than dense supermarket tempeh.
What is tempeh?
Tempeh is an Indonesian dish where mold breaks down soybeans (or other plant-based proteins) and binds them together into a solid cake. The fermentation process is not only delicious, but it also turns soybeans into a complete protein that is easily digested. Tempeh is also more likely to be tolerated by those who might otherwise have trouble with digesting soy.
Tempeh has a nutty flavour that is delicious all on its own. However, it can be smoked, marinated or barbecued which allows for all sorts of interesting serving options.
Homemade tempeh basics
If you’re new to fermenting or new to tempeh here is some basic advice.
- Cleanliness: It’s important to keep things clean as you go along because you don’t want to accidentally grow the wrong type of fungus.
- Culture: You might be able to find the starter at an Indonesian grocery store, however, you can also find it online (affiliate link.) Don’t forget to make your own starter for future batches.
- Fermenting Container: The tempeh needs to be loosely spread out, about 2 cm deep, in a vented container for proper fermentation. You could use a vented plastic container, a baking pan covered with plastic wrap with holes poked in it. However, the easiest way to make tempeh is to use a ziptop bag with needle holes poked through at 1 cm intervals.
- Incubation Options: The other tricky part about making tempeh is that the starter needs to be incubated at around 85-90 F. Luckily I have Brød & Taylor Bread Proofer & Yogurt Maker (affiliate link) which works well for all my heated ferments. Other options include incubating in the oven with the light on, near a radiator, or a hot water heater. Many people use dehydrators (affiliate link) set to the right temperature for incubation. You can also use a cooler kept warm with jars of water heated to the right temperature. The only trick is to measure the temperature as you go along because tempeh starts to self-generate heat as it ferments. The right temperature is important because if it’s too cold your mold won’t grow, and if it’s too hot you will kill the spores.
The hulls of the soybeans need to be removed in order for the spores to inoculate the beans. There are two different methods to remove soybean hulls.
- Dry method: If you have a grain mill or a meat grinder then it’s easy to dehull soybeans. Soak the soybeans then put them through the grinder on the coarsest setting. You want the beans to be just split in half, so if they’re coming out too fine then this won’t work with your grinder. Once the beans are split put them into water so that the hulls can float. Massage the beans to loosen up all the hulls, then drain off the floating hulls. You may need to massage the beans several times to make sure that you’ve gotten rid of all the hulls.
- Wet method: After boiling the soybeans, massage the beans so that the hulls fall off and the beans split in half. The hulls will float to the top, so drain off the floating hulls as you go. This is quite time-consuming, so if you find yourself making soybean tempeh a lot, then I’d suggest that you buy a grain mill.
How to Make Tempeh
Homemade tempeh is creamy, nutty and delicious. It is so much tastier than supermarket tempeh. Here is everything you need to know about how to make tempeh at home.
- Prep Time: 1 hour
- Cook Time: 20 minutes
- Total Time: 1 hour 20 minutes
- Yield: Serves 4–6 1x
- Category: Main Dish
- Method: Fermented
- Cuisine: Indonesian
- Diet: Vegan
- 1 lb dried soybeans (about 2 1/2 cups)
- 2 tbsp white vinegar
- 1 tsp tempeh starter
- Cover the soybeans with water and soak for 12 -18 hours. If you are using the dry method for dehulling, pass the beans through a grinder at this point. Otherwise, dehull after boiling. See the section above for more information.
- Bring the soaked soybeans to a boil and simmering until they are soft but not mushy, (about 1 hour).
- Drain the soybeans and gently pat them dry with a towel, then allow them to cool to just below body temperature.
- Mix in the vinegar (to lower the pH so that unwanted bacteria won’t grow.)
- Sprinkle on the tempeh starter and mix well so that the beans are evenly covered by the spores.
- Fill the fermentation container(s).
- Incubate at approximately 88 F (31 C).
- Check the beans after 12 hours. At this point, the mold will have started to grow and the beans will start generating their own heat. You may need to lower the temperature.
- At some point between 24 and 48 hours, your tempeh will be finished. You will know it’s done when the mold has thickened the soybeans into a single dense mass. There might be some grey or black mold too, but you want to stop before there’s too much black mold. See the photo above for a picture of the white mold.
- At this point stop the fermentation by transferring the tempeh to an airtight container and storing it in the refrigerator for up to 1 week. (See notes for cooking and freezing instructions).
- Black and gray spots may appear on the tempeh. These are the mold spores, and they are completely edible. The tempeh should smell nutty, mushroomy and it might have a hint of ammonia. If it smells bad, is mushy or slimy then throw it out.
- In general, it is tastier if you stop fermentation before the mold starts to spore. However, if you want to save mold spores for future batches, you can find instructions here.
- Tempeh can be eaten raw, though it is generally steamed before eating. Steaming also stops the mold from spring. To steam, remove the tempeh from the fermentation container and steam for 20 minutes in a steaming basket or a colander over a pot of boiling water.
- Steamed tempeh will last in the fridge for 2 weeks or can be frozen for up to three months.
Keywords: vegan, vegetarian, gluten free, protein, diy, homemade, soybean, how to make, fall, winter, spring