Monday, February 13, 2012

Homemade Tempeh: An Illustrated Guide

After waiting for about three weeks, I got a little package in the mail.  
 Return address: Gem Cultures, OH YES.

It’s my Powdered Tempeh Starter (P.T.S.)!! 

And I love the packaging and the graphics of a tiny tempeh burger and two tiny tempeh skewers, OH YES. 

I also found this note of apology inside the package and thought it a very nice touch since I was about to email them to check on my order. But, instead, I followed the directions on their website.  They clearly tell you to wait THREE weeks and if AFTER three weeks you haven’t received your order, then you may contact them. I got my order exactly three weeks after I figured they received it.  Even though it was still within their time frame, I really liked the note.  Nice touch.  

 And some cheesecloth for more, upcoming fermenting adventures.

OK, should we get started making this tempeh or what?? I'm going to do this pretty much like a picture based tutorial, because there are so few online resources available on actually MAKING tempeh.  Lagusta's wonderful post is the only detailed, online tempeh making guide I know of, and thank goodness for it (and for her help with my tempeh questions in the last few months to prepare myself for this day!).  She also details making the incubator I replicated, but I'll put my notes about making that here (or in a separate post) as well.  I had to make some minor modifications to my incubator, so it isn't exactly like Lagusta's but I'll explain that later.  The recipe I used is the same recipe the PTS kit gives you in their booklet, and the same recipe as Sandor uses in Wild Fermentation (a great book!), and 1/3 the size of Lagusta's recipe.

What you need: 
Dry beans (soybeans or chickpeas, I'm sure other kinds work, too)
Powdered Tempeh Starter 

That's it.  The incubator is the real bear, then, doing the process for the first time is a bear, too :-) But now after doing it once, I can see it will flow quite easily.

First, the recipe.  It's 2.5 cups of whole, dry soybeans (I used soybeans this time since they are cheap and I didn't want to mess up organic chickpeas on my first tempeh attempt.  Next time, organic chickpeas!)
2 Tablespoons of vinegar (I used unfiltered apple cider vinegar) 
1 tsp of Powdered Tempeh Starter (P.T.S.) for each pound of dried beans

This recipe yielded me four blocks of tempeh (that fill a small "snack" sized zip lock bag).  I'm sure I lost some bean volume in the "skimming" process as you will soon see :-)

First, soak your 2.5 cups of beans (I used soybeans, but next time I am using chickpeas) in unsalted water 6-8 hours or overnight.  Next, "dehull" the beans by chopping the soaked (and still uncooked) beans up in a few batches in your food processor until the beans are broken up "in three to four pieces."  The soaked beans started to shred on me, so I got some teen tiny pieces and some whole beans, but I guess on average, it was correct.  

 This is what my soaked and then chopped up soybeans looked like after coming out of the food processor.

Now, you are going to cook the chopped up beans for about an hour, until barely cooked (you will be able to bite or cut through them but you wouldn't want to eat them).  This is probably about 30% of the normal cooking time.  During that time, you are going to do some serious foam skimming, OH YES.
 As you cook the chopped beans, tons of foam will rise to the top, loaded with, you guessed it!  Hulls. Skim them off.  I used a spoon with holes in it.

 After you skim quite a few batches of foam off, a skin will start to form (because now, essentially, you are making soy milk!). Skim that skin off, too.

 Here is that "skin" with my skimmer spoon.  You can see I accidentally got some beans in my skim.  I think I lost some tempeh volume this way, but wanted to be safe rather than sorry.

 Once hulls, foam and skins stop rising to the top of the pot and you have nice looking soy milk with beans in it, you are done. This took me about an hour of cooking time.

Now, strain your beans, and save the milk if you want to (it's soy milk!).
 This was my system.  

 Here's the milk you are left with!

Add some sugar or agave, a little salt, some vanilla or other flavoring and you got yourself fresh soy milk! P.S. Don't you love this glass pitcher? It's hermetically sealed.  The Italians really know what they are doing.

Now, take those cooked, well-drained beans, and spread them out on a baking sheet.
 We are going to let them air dry vs. towel drying them (no, thanks).  
Despite Lagusta's sage advice to only leave your beans on the trays for "a few hours," I ended up having to leave my beans to dry for like 24 hours! I covered them loosely with AL foil at the 8 hour mark on Saturday night when I realized I wasn't going to make tempeh after getting home from a friend's house at like 9pm (I have a four year old, so tempeh wasn't happening until Sunday!).  The beans were drier than I would have liked on Sunday, but still seemed to have enough moisture to go forward.  


 Mix your beans, vinegar and half the spores thoroughly.  Add the other half teaspoon of spores 
and mix again.

Pack into containers (I love these snack sized zip locks for nice portions).  These bags were poked through with a fork every few inches to make air holes for circulation.  You'll see the fork marks later in the finished product.

Now, you are ready to load up your incubator!  Here's mine!
 You might notice that the incubator station is in the same location as the Triops growing station (RIP, T!).

 I had to make a freestanding lamp out of my lamp-kit bulb because I couldn't lay it down on the floor of the fridge where it would have fit best (the plastic floor started melting when I tried).  I also couldn't use the rack that came with the fridge because of the height of the bulb, so I measured and then hot-glue gunned some chopsticks together to make movable racks for the tempeh. Success! 
 Load it up with your tempeh.  Try to give enough room for plenty of air circulation.

Incubate at 85-90F (I did 88 degrees) for about 24 hours.  Crack the door of the fridge at the 12 hour mark (this is when the tempeh starts generating its own heat from fermentation and you need to accommodate for that).  Here's what happened to me, though:

I set my (new, untried and untested, obviously!) thermostat to 88 degrees starting the tempeh at 1pm yesterday (on Sunday).  I didn't bother setting the time or anything because I figured not setting the clock and setting a single temp would override any default functions. WRONG.  I last checked the tempeh around 9:30 pm Sunday night (last night) and it was going along fine at 88 degrees.  Fine, I'll go to bed and get up later to check it (around 1am), well around 1am, I didn't get up because I had a toddler in the bed with me :-) So, I couldn't sleep anyway this morning and got up at like  5:15 a.m. When I checked it at 5:30 a.m., it seemed to have turned totally OFF and was 62 degrees., I re-set it to 88 and pressed the "hold" button.  Then, I checked the manual that came with the thermostat I am using and it apparently has a default setting when turned to "heat" that goes down to 62 degrees at 10:00 p.m. Oh, perfect, yeah, great.  Anyway, I just figured that I could tell if the tempeh were badly affected in the end product.  The tempeh got 9 hours of incubation at 88 degrees (1pm to 10pm) and needed about 11 more hours, so, I turned it right back to 88 degrees at 5:30 this morning and let it chug along all day until about 5pm tonight.  I checked it regularly, and cracked the door at about 12pm when I thought it would be hot enough to do so (and I saw signs of fermentation happening, so I knew it had internal heat at that point).  At 5pm (about 20 hours of fermentation) I got THIS!!!
Perfect looking (and really amazing and delicious smelling) tempeh.  I know because I had Lagusta's homemade tempeh and this looks and smells exactly like it.  OH YES.

So, there is an important lesson here: I had two potentially problematic issues: drying the beans for 24 hours instead of a few hours and losing eight hours of fermenting time overnight, but with adjustments, the process still worked just fine.  I remained calm and had faith in my cooking experience and my knowledge of biology and chemistry.  It worked.  Horay!  I wanted to share this with you guys in case you try it and it doesn't go perfectly.  It doesn't have to.  You can make adjustments and figure it out and IT WILL WORK.

Had my tempeh been pink or orange or smelled bad or I had ANY question about it, I would have started over.  But, I persevered, and here it is, all worked out and fine.  

I'm so excited to try my homemade tempeh! 

And the first recipe will be...

Something with three fermented foods, together in one recipe.  

Any guesses??


  1. WOWW! I LOVE fermented foods but have only made nut cheeses, pickles, sauerkraut and sourdough bread. Fermenting fascinates me!!
    Not sure how I would have room and supplies for the whole incubator... wondering if somehow a dehydrator could be covered and rigged?
    Anyway, I may stick to store bought tempeh, but this is AWESOME!

    (And my bet for your first recipe? A sourdough-tempeh-kraut reuben sammich?)

    1. Hi Marti! You have made a LOT of fermented stuff, yeay! I still have to do the pickles and sauerkraut, and really fermented nut cheeses (I have done unfermented ones). Do you have posts up for that stuff?? :-))))

      Actually, you could put this little fridge anywhere out of the way, including basement or whatever, as long as you have access to an electrical outlet to plug it in (and I think it will even run on the thermostat's battery, but not sure for how long). I just happened to have a table for it (rare, I know to have an actual SURFACE to put things on with kids around, right??).

      You can rig an insulated Styrofoam cooler box, I think, more easily. The box/incubator should be able to hold heat very well, so you aren't constantly having to supply energy. And, you have to be able to get a hole in it that leads to the outside (I'll post about the incubator a bit more later) for the temperature probe to poke out of and for the plug to get through. You could easily cut through a styrofoam box and do what you needed to do and they are cheap!

      A tempeh reuben, huh? Hmmmm...sounds like a pretty good guess to me!

      Thanks for your excitement, you should try this it is wild (and a great science project for the kiddos)!!!


  2. You are amazing! So awesome! I did this with a rigged styromfoam cooler back in the early '80s... have to figure out a way to do it again. There is nothing like homemade tempeh!

    1. Thanks, Tami! Yeah, I think a styrofoam cooler would be easiest (unless, like me, you had a little fridge that you didn't need to be a fridge anymore and could convert to a tempecubator!).

      I'll post the incubator post soon, but please feel free to give us any tips/tricks with the styrofoam incubator that you remember, especially design options! I suspect that's what most people would go for, since you can get them all over the place, they are cheap, and easy to cut holes in :-)

      Now, I will never have to buy that store bought stuff again! SO exciting.

      Do it, Tami, do it!!


  3. Great job explaining it all in pictures. It looks pretty easy - except building an incubator!

    1. Thanks! I'll put up an incubator post soon. It's not TOO bad, don't worry. Totally worth it for homemade tempeh for the rest of your life!


  4. All I remember is that it was really basic. It had a light bulb inside and I shoved a baking rack in it to keep the air circulating......I definitely have to figure something out. I'll keep you posted! :)

    1. Yeah, I think styrofoam would be a nice option because it is so malleable (in addition to being cheap and a great insulator!). You can probably "scrape" baking tray rack guides/tracks right into the insides of it with the appropriately sized tray! And you can maybe even stand the light bulb straight up if you sort of mash it down into the bottom of the box, or cut a bit of a hole out to push it into (I would still think that a hot enough light bulb would melt the bottom of the styrofoam box if it was laid down flat inside it...).

      Incubator post to come!

  5. Dawn! You're so hardcore with the tempeh making, I'm super excited for you! And a little envious, ha ha! Because tempeh is like a zillion dollars at the store but to make it at home would be so cheap. One day... Great post though, super comprehensive!

    1. Allysia, Thanks!! And, you are SO right about the cost. It literally only cost me 65 CENTS for the soy beans and probably 50 cents for the tempeh starter to get four full servings of tempeh like what you would buy in the store. So, for about one dollar, I got four store-sized tempeh packages. That's a quarter a piece! 8 ounces of store-bought tempeh usually goes for like $3 to $5 dollars here!!

      I spent about $50 total to get the thermostat ($40) and lamp repair kit ($10? I think?), so I have to recoup that cost, but it won't take too long, since this will work for a long, long time, I'm guessing.


  6. well done Dawn, great blog, I have a tempeh business in Australia and do mailorder for kits and spores etc. The incubator is a problem for most people so I have developed a waterbased incubator, cheap to make and safe.use an aquarium heater and a suspended basket in a styrofoam box and you have a great incubator, I will try to find a photo of my testmodel and attach it, if not please send me ur email adress and I will send it directly to you and you can add it maybe.cheers Amita

  7. Sounds great. Think I will use my large size cooler, using an indoor/outdoor thermometer ($14/99 at Amazon), place the wireless temp sensor inside with a christmas candle for the heat, and hopefully, voila! The temp should remain constant and I can monitor the temp with the digital wireless readout.

    Thanks so much!

    1. Linda, did you try it? The candle as a heat source makes me quite nervous (the thought of a burning candle in a cooler activated my "mommy mode!" :-)

      Given the 24 hour incubation period, I am also curious as to how you will monitor it overnight?

      OK, I'm sure you'll be safe, do let us know how it works out!

  8. My compliments on your wicked incubator Dawn! I love how you descriped your process of making fresh tempeh! I'm from and I would like to ask you something in private, but I can't find your email. Would you be so kind to contact me?


  9. Why did you crack the door to 'account for the heat generated by the tempeh'? Isn't the point of a thermostat to regulate the heat?

    1. The thermostat measures and regulates the *air* temperature, yes, but it does not account for the *internal* heat generated by the tempeh itself through the fermentation process.