Guacamole is a highly perishable food. The high fat (mostly monounsaturated) content of avocados means it goes rancid quickly. Even with its low carbohydrate content, you can still ferment it because you’re using other veggies as well as a kickstarter to get the good lactic acid bacteria going. Note that due to its perishability, fermenting guacamole is done to add a probiotic kick rather than to preserve its shelf life.

I start by making fresh guacamole. I keep and use half of it fresh. For the other half, I add some pickle brine to kickstart the fermentation process. After 2 days on the countertop, telltale bubbles formed. It was slightly tangy but I decided to wait one more day. BAM! On the third day it had just the right level of tanginess.

Avocado oxidizes (and turns brown) quickly when exposed to air. I try to prevent browning by placing plastic wrap directly on the surface of the guac. You can also use lemon or lime juice to slow the browning. Even under wraps, it still browned a little.

Using plastic wrap also signals to you know when the fermentation is going– see pics below!