Corrigan cleaned behind the counter at the bike shop the other day, and I snagged a big old thermos he was going to throw out. Instead of going through the whole yogurt making process, I filled it with hot water from the faucet, closed it up, and wrapped the whole thing in an insulation blanket I got from American Science & Surplus.
The temperature at 8:45, when I left for work, was 110°F, and when I returned home 11 hours later, at 7:45, it was at 95°F – a loss of only 15°F! I’m hopeful – today I’m going to heat some water on the stove to about 125°F and try a yogurt incubation experiment for the rest of the day. (Remember – the ideal yogurt-making temperature is 110°F.)