Fermentation Temperature and Time
Seasonality impacts temperature and temperature affects time.
We may regard temperature as a catalyst for fermentation. Bacteria, just like us, have an ideal temperature to survive. The warmer the weather (to a certain degree), the more active the bacteria, and the faster the fermentation. We know from our previous post that LAB is responsible for fermentation. Keep in mind that LAB is an order of fermenting bacteria, not a species (remember your grade 10 biology acronyms?). Therefore, some LAB prefer warmer weather, and some like it a little cooler. Our job is to pick which one makes tastier kimchi. For example, L. mesenteroides is active at 30 Celsius and produces a tiny amount of ethanol – giving the kimchi a slight boozy flavour. Whereas, Leuconostoc lactis creates acetic acid, giving it a sharp vinegary taste. All of these strains of bacteria compete for space and food to reproduce. With the relationship between temperature and fermentation, we can hypothesize that summer kimchi will ferment fast and will have a strong flavour (I once fermented kimchi in Thailand and It only took 3 days). Fast fermentation is also a sign of one dominating bacteria culture, and often gives one flat sour note. Whether this is desirable, it is a matter of taste. If you like sour and robust kimchi, summer kimchi is for you.