When It Gets Hot in Chicago: Make Tempeh!

Tempeh image from Wikipedia.

Today, a guest post from Nancy Klehm, writing to us from Chicago, in the midst of an epic drought and heat wave. Here’s Nancy:

A Drought of Inspiration

Until last week, we were at 12% of our normal precipitation for our eight month growing season. This, plus extreme temperatures, made us delirious when some humidity blew south from Canada and was sticky enough to grab ahold of some clouds and build them until they spilled rain. And yet, the GM soy is limp and the GM corn is dwarfed and tasseling weakly. The effects of which will impact all of us who shop and drive cars.

And frankly, we’ve been spoiled by the drought and heat – it’s always sunny and dry (just like L.A. and Phoenix!) no rain to spoil your bike ride, BBQ, or outdoor gardening. And the biggest benefit: No Mosquitos.

Put this in your bookmarks: US Drought Monitor droughtmonitor.unl.edu/

The rough side of our weather is obvious. Due to July temperatures in March immediately followed by appropriate, but ultimately harming coolness, we lost most of our tree fruit production. Local orchardists turned to growing supplemental vegetable crops. There are none or not many apples, Asian pears, peaches, cherries or plums this year. No pawpaws. What we are left with is heat-island city fruit, and shrub fruits of currants, gooseberries, black raspberries, blackberries, strawberries, elderberries, wild plums. But it is a okay pear year and I will be getting some American wild persimmons. Hubba Hubba.

And so I concentrate on the fact that this climate is prime to dry just about anything – and to fermenting my year’s supply of tempeh and the koji needed for my fall miso and tamari production.

I like to ferment passively, using the wide range of microclimates of my non air conditioned house. I have no uniform temperature control in my house, in spite of having a thermostat and I like it that way. It makes for a broad spectrum of air humidity and temperature that allows me to situate the different fermenting processes appropriately.

Tempeh: a passive ferment

Tempeh is a relatively quick ferment of 8-12 hours when temps are between 85-95 degrees. Tempeh is dang tasty. It is basically beans partially digested by and knit together with mold or as some would prefer to say, a ‘mushroom’ called Rhizopus oligosporus. Because it is fermented, it is a more highly nutritious and easily digestible soy form then is tofu or soy milk or the beans themselves. It is easy enough to make and relatively easy to jump the spore onto other substrates, i.e. experimental combinations of grains and legumes. The tempeh dance is easy enough and even easier to riff off of:

Soak selected beans and grains 24 or more hours for a primary fermentation, then under cook them (soft enough to bite, but not soft enough to enjoyably eat), drain and dry the beans/grains of residual moisture with a towel and allow to cool. Toss with the tempeh starter and a touch of vinegar and pack ½”-3/4” thick into ziplock bags that you have pierced holes through with a fork. Place in a dark place and allow the summer heat to do its job. Depending on atmospheric temps, this will take anywhere between 12 and 24 hours.

The tempeh is done when it is white and caked together with mold, maybe with some grayish or dark areas near the fork holes where the mold has started sporulation. Use or freeze immediately or the spore will keep running. Delish!

Next time: Koji.

My favorite, family-owned, tempeh spore source: GEM cultures.com

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  1. good site folks!!

    am looking for some Aspergillus flavus var. oryzae spores aka koji -> [email protected]

    what i think ive understood about the koji-principal:

    it should be feasable:
    get spores on substrate like humid (NOT!!! wet) natural rice: allow to sporulate (before using make sure the color of the spore-lawn is evenly … if NOT: discard or extract just these evenly spots…) and extract JUST THESE next generation spores on fresh milled dry rice: this IS koji-starter now!!

    the problem with Aspergillus flavus is:
    they DO produce aflatoxins!!
    BUT fortunately only AFTER MORE than three days inoculation time…!!!!

    to transfer JUST the spores!!! avoids uptake of these aflatoxins safely as the spores itselves contain NO aflatoxins!!

    so the trick is to propagate just pure-cultures of spores… AND ALWAYS!!!! finishing the koji-process after 72 hours max.!!!

    well, if you can:
    to work under sterile conditions would help BUT should NOT to be mandatory -i wanna try it out!!

    for tempeh the system is analogue -though simpler-:
    just buy fresh tempeh (if not pasteurized or freezed after production: let sporulate: means within about two more days under a rather warm and NOT TOO dry climate… you get a pure BLACK!!! surface: then you got a pure-culture: transfer these spores to freshly grinded rice: this IS your new starter already!!

    ps ps
    maybe you start a new post called:
    koji-starter for shoyu, soysauce, sake, miso…

    from Biotechnology Program under the Toxic Substances Control Act (TSCA):
    > …Aspergillus oryzae is a member of the A. flavus group of Aspergillus species. The A. flavus group, which also now includes A. sojae, A. nomius and A. parasiticus (see below) is defined by the production of spore chains in radiating heads which range in color from yellow-green to olive brown. The conidiophores are roughened and colorless. The spores themselves have conspicuous ridges and echinulations (spines). Sclerotia are occasionally produced (Raper & Fennell, 1965). A. oryzae/flavus species have never been connected to a sexual or teleomorphic stage. However, the teleomorphic stages of other Aspergillus species have been demonstrated by the formation of cleistothecia. These species belong to the genera Emericella, Neosartorya and Eurotium, all belonging to the ascomycetous family Eurotiaceae (Fennel, 1973). Either the sexual stages of the A. flavus group have not been recognized as such, being identified as completely different species based on morphology, or this group of fungi are “degenerate”, having lost the ability to form sexual spores and mycelia…

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