Mesophilic yogurt is easy to love—no heating, no fancy equipment—but when it turns out thin or runny, it can leave you wondering what went wrong. This guide walks you through the most common causes of thin yogurt and gives you simple, countertop-tested fixes to help thicken things up (without stressing your culture).

Not all fermentation is the same—and knowing which type you’re working with can change everything. In this post, we explore the three major types of fermentation most home fermenters encounter: lactic acid, alcoholic, and acetic acid. From yogurt and sourdough to kombucha and vinegar, we unpack what’s really going on in your jars and how to use that knowledge to improve your results (and save a few batches).