Making tempeh is one of those projects that demonstrates how amazing home-fermented food can be when measured up against its pasteurised, store-bought alternative.
The aroma of a freshly grown batch of tempeh is incredible – floral, aromatic and mushroomy, and will differ depending upon the ingredients you use to make your tempeh. Making it is remarkably simple, provided you have the ability to keep a tray of tempeh at a stable temperature for around 40 hours. That is because the spores of the fungus Rhizopus oligosporus need a nice warm environment in which to grow and colonise the material that you are inoculating.
Very much an artisanal process, because every legume or grain that you use to make tempeh – and the options are very broad and varied – will grow in a slightly different manner. So not only is it important to be disciplined about hygiene and keep a keen and watchful eye on the process, it’s also important to understand that not all batches will be successful and to not be put off if one fails.