Probiotic starter cultures come in many different flavors. Here are two that qualify as Not-off-the-shelf.
1. “Characterization of Lactic Acid Bacteria Isolated from Infant Faeces as Potential Probiotic Starter Cultures for Fermented Sausages.” This study was honored with the 2014 Ig Nobel Prize for nutrition.
2. Vaginal bacteria as probiotic starter culture for yogurt. Janet Jay, writing in Motherboard, tells the story of how this recipe came into existence, under the headline “How to Make Breakfast With Your Vagina“. Rosanne Hertzberger ponders the result. (Thanks to Charles Oppenheim for bringing this to our attention.)