- It is vital that you use carbonation-safe bottles for secondary fermentation. This recipe makes 6 cups, so I use three 16-ounce bottles. You can use fresh-pressed juice (see notes) or bottled pasteurized juice; both work great (ensure it’s 100% juice, no additives).
- Fill a carbonation safe bottle about 1/2 full with fermented sugar water from primary fermentation.
- Top off the bottle with the coconut water so there is about an inch of headspace left in the bottle.
- Secure the bottle lid and gently invert it a couple times to mix.
- Allow it to ferment at room temperature (70-80 degrees F) for about 24-48 hours.
- Carefully open the lid to see if it is carbonated to your liking. If it is refrigerate, if not continue to ferment for 24 more hours, carefully checking the carbonation again.
- Keep refrigerated.
