degringolade | Going Full Nerd

So the first batch of tempeh worked pretty darn well. Tastes like tempeh. I used black beans because I have a lot of them right now and they are pretty cheap. It took about four days to ferment and the temperature was all over the place, but it worked, so I am pleased. Now I need to not get cocky and see if I can reproduce the process a couple of times.

So today is using up the last of a bag of red beans. 516 grams left. I weighed them out and put them right into my pressure cooker (5-liter) with two tablespoons of apple cider vinegar and added up to the 2/3 mark (around 3 liters) and stuck it on the small burner (1400w) on high (100% power draw) and brought to a boil using a standard lid, this took exactly 15 minutes. I then stuck on the pressure top and lowered the setting to medium (65% power draw)and let it build pressure for seven minutes. Then I turned the temp down to medium low (45% power draw) and let it cook for another eight minutes. Then I turned the power off, kept the pot on the warm burner and let the beans cool for three hours in the pot.

Active power draw equals fifteen minutes on high = 1400w x 0.25 hours = 0.350kWH
Active power draw equals fifteen minutes on medium = 1400w x 0.65 x 0.25 hours = 0..227kWH
Active power draw equals fifteen minutes on medium-low = 1400w x 0.45 x 0.25 hours = .0.158kWH

Since I am on a time-of-day electricity use plan and this is being done off-peak, I pay $0.0839 per kWH. Added together this comes up to 0.75 kWH used to cook the beans. 0.75 X 0.0839 makes the cost to cook the beans as $0.07.

The beans themselves were cheap. If memory serves, the 10 pound bag (4536 gram) was $12.00. So $0.0026/gram. So the cost for the beans themselves is $1.35. Once they are cooled to around 90 F., I will put them in a gallon ziploc (I figure $0.20) and add in another two tablespoons of apple cider vinegar. Best I can figure this stuff runs about $0.10 per tablespoon, so the whole recipe cost for vinegar is $0.40.

Today is the spendy first cultivation using purchased starter. Until I produce my own starter from this batch, the cost of the tempeh will be high. The initial starter cost for this batch is $4.00.

Finally, the electricity cost for incubation. My heating mat for rooting draws 20W. I will probably need to run it around 4 days.

20W x 96H = approx 2kWH running at the average of $0.17 per kWH so power draw for incubation is around $0.34.

So altogether, this batch of tempeh cost me around $6.40 to produce. I am figuring a yield of around 2 pounds. But this made with spendy starter purchased from yuppie women with expensive cars that do it part time. I should get a lot cheaper as I work through the process. Next process will be using the spendy yuppie starter to make my own starter.

Estimate cost is $3.20 per pound for this pilot batch. I am hoping to do a lot better than that in the future. I figure that I should be able to make tempeh at around a dollar a pound.