Novice Tempeh Problems and Headaches

[buster]

Hello Everyone,
I have been trying very hard for the last few months to successfully make tempeh. Unfortunately, I'm allergic to soy products so I can't consume tempeh that is sold in the stores. I have more or less failed on my first 5 attempts to make tempeh, which is causing a lot of frustration. I am attaching pictures of my last tempeh batch as well as my incubator setup. I hoping that someone can help guide me in the right direction.

The attached photo shows my setup (Pic 2). I am using a cooler partially filled with water along with a aquarium heater. The heater is set to 89 degrees. The temperature generally swings between 85 and 92 degrees.

I am using white Navy Beans for the tempeh and a tempeh starter that I purchased online. As a side note, I don't know how to efficiently dehull the beans. I've seen videos of people just rubbing their hands together under running water. These hulls require a lot more pressure to remove than just rubbing between the hands. I am spending a tremendous amount of time trying to pop the hulls off of the beans. If anyone has any better ideas, please let me know!

I am also using a silicone bag to ferment the beans. I am trying to get away from using plastic to ferment the beans. (Please see attached Pic 4). You will notice that there is a gap at the end of the silicone bag. Perhaps this is what is causing the black mold that I am concerned about? Maybe there is an air gap problem?

After 3 days in the incubator, my latest batch had some black mold growing. I don't know if it is safe or desirable to consume?!? See attached Pic 6. Does anyone know what is causing this? I have more pics, but I am at the 3 attachment limit.

I have tried very hard to study and practice tempeh making. At this point, I am at the end of my rope. I have had to toss 5 batches now. As a last resort, I even tried making the tempeh in my Insta Pot on yogurt mode. That failed as well!

Thanks in advance for anyone that can help.
Terence

[Christopher Weeks]

There are very accomplished Tempeh folks that will hopefully wander by in the next few days to answer, and I am a rank novice, so take what I say with a grain of salt. But, that black looks to me like sporulating Tempeh, and not a bad mold. IIRC, you might not like it -- I'm pretty sure it's undesirable, but not dangerous like a foreign mold infection. But let's wait for expert advice before you start munching on it. :-)

[ArthurDent004]

If you are looking for more information about tempeh making and have a Facebook account you can join the tempeh makers FB group.

Generally you only need to dehull beans with thick skins like soybeans, other beans don't have a hull thick enough to worry with. If you expect to make a lot of tempeh you could use a grain mill to split the beans. That way you really don't need to worry so much about hulls. Other options I've seen is using a stand mixer to stir the beans around to help remove hulls. Other options include pulse your beans in a food processor to chop them up or using a rolling pin or potato masher to slightly smash the beans to give the mold access to the beans.

Another thing you can make tempeh from is lentils, legumes, beans, and pulses - https://indiaphile.info/guide-indian-lentils/

As far as using a silicone bag you can do that but you want to minimize any gaps by rolling the bag down and clipping it in place with clips. Also you want to smooth the bags to get a uniform flat surface. Any air gaps are where moisture will accumulate and where you will see black spots - https://fermenterskitchen.com/black-spots-on-tempeh/

As far as incubation time my tempeh is generally ready after 26 - 32 hours total incubation time. You can check my previous posts to see my results. You mention the temperature swings of your incubator but are you measuring the internal temperature of the tempeh itself? Tempeh generates its own heat as it incubates and after 18 hours I can turn off my incubator.

I hope you can join us in the tempeh makers FB group where you will have no limit to the number of photos you can post.

[buster]

Hey Christopher,
Thanks for sharing your input! I am along the same lines of thinking as you are. I think that this could be sporulating mold as well (due to the air gap in the silicone bag). Most of the black mold was concentrated by the air gap at first. But then a dusting of black mold started to show up on other parts of the tempeh cake. Per Arthur's comments, I think that I need to readjust my fermentation time and shut the incubator down after 18 hours or so. I'm probably heating it for too long as well.

Arthur, I will definitely check out your other posts. Thank you for all of your helpful tips and suggestions. I have no idea why there are so many different versions of making tempeh! It's incredible when I think about everything that I've read and viewed online. That said, your suggestions have "demystified" the subject for me quite a bit.

Arthur, do you have any suggestions for a reliable grain mill that you or others have had good success with? I will try a batch of beans without the dehulling process and see what happens. I also have a stand mixer, so that sounds like an interesting option as well. Great idea!

I also purchased a new silicone bag (see attached pic). I think that this will help minimize the air gaps on the next batch. Now I have to get my self esteem up so that I can reattempt another batch, LOL! I still feel beat down after so many failures! I still remember the smell of the overripe mold in my Instant Pot. Oh, it was terrible. The smell got stuck in my nose for several hours and I had to throw away the silicone insert that I was using. But now I know!

I greatly appreciate both or your helpful suggestions. Thanks for taking the time to respond and help me with me problems. It means a lot to me.

Enjoy your day,
Terence

[ArthurDent004]

I've never used a grain mill so I can't help you with a recommendation. If you want to buy one you should decide if you want one that is manual or electric. Here's one of the many guides you can find online - https://foodal.com/kitchen/general-kitc ... -reviewed/

Making tempeh is both an art and a science. There are some many different articles on how to make tempeh because everyone's situation is different. They are describing how it works for them but their method may not work for you unless you can replicate their experience exactly. I read about how to make tempeh but I didn't have a successful product until I came across this article - https://fullofplants.com/how-to-make-te ... stant-pot/

The more tempeh you make the more experience you gain as to what works for you. I have moved on from using my Instant Pot to using an incubator I put together from parts I had available. I used to use a kitchen thermometer to check my tempeh's temperature but now I use a Bluetooth meat thermometer that I can monitor from an app on my phone.

[buster]

Hey Arthur,
You said "Making tempeh is both an art and a science. There are some many different articles on how to make tempeh because everyone's situation is different."

I think that you nailed it. That sums up my experience exactly. This is why I had so much trouble following what other people were doing online. I wasn't matching their culture, set up and environment. I didn't realize that the process was somewhat of a unique art form in every situation.

I like what you said about gaining experience. I will try to keep making the tempeh until I get better and learn more. I've already learned quite a bit from all of the mistakes. I'm just not accustomed to eating anything with black mold on it, LOL! Hopefully in the future I will be able to eliminate the air gap problems.

Thanks a million for you links to the grain mill site and tempeh making. This information is very helpful! I greatly appreciate your time and feedback!

Have a good one and happy fermenting,
Terence