My olives have been brining for 2 months, and are still quite bitter. I read to keep them in a cool place, here in Arizona when I started this process it was still in the 90's so I put them in the fridge. Is this too cold for the brining to work? How cool should it be? There is no basement here and the floor temp is about 68º. Will this be cool enough?
There are five treatments to process olives: Water cured, brine cured, dry salt cured, lye cured, and lye cured fermented. The main objective when curing olives is to leach out the oleuropein, which is the bitter compound found in fresh olives, and to ferment them, which improves the flavor and, of course, improves the shelf life.
It sounds like you are using the brine cure method. Oleuropein is water soluble. Chemically, the salt brine breaks the bonds between the oleuropein and sugars, allowing it to leach out.
So, first, you should replace the brine after the first week of curing, so that the leached our oleuropein is removed. Then, from what I gather by reading this, 2 months is the minimum curing time.
Curing time is impacted by temperature, salt concentration, and acidity. These factors can slow or speed the time. It looks like their recipes for brine cured olives proceed in a temperature range of 60 - 90 F (15.5 - 32.2C). Further, they recommend a 2 to 3 month cure (2 if you like more bitter olives).
So, I would suggest that your cure is happening very slowly because of the refrigerator temperature. It seems to me that your room temperature is ideal. I would just remove them from the fridge and check in a couple of weeks.