1977 early – The Farm (Summertown, Tennessee) starts selling America’s first commercial tempeh starter. It is made by Cynthia Bates. In 1977 when Farm Foods was founded, it took over marketing of the tempeh starter. They also sold America’s first Tempeh Kit, made at The Farm.
It’s incredible, so your community The Farm was at yet another turning point of history! The right crowd and the right time, I guess :-). Did you sell the kit for making tempeh at home, including the spores production? Also, do you eat it to this day? From what I’ve seen, like soy, tempeh consumption has been on the rise ever since. It is not very popular in Europe outside of the Netherlands, but hoping we’ll get more of it in the near future! We bought and read The Book of Tempeh (1979), indeed a Bible 
The real innovation I find it to be that you can ferment not just soybeans, but all sorts of beans, peas, chickpeas, lentils, even peanuts! Others also add quinoa, sunflower seeds and other stuff in it… But you can focus on just the local produce around you, that you buy in bulk. And most beans tempehs are super yummy.
About the yeast, I will have to read more and get back to you on that… Not sure what version of it is healthy and popular today?