For a more fruity flavor, use 4 ounces of juice. If you're concerned about sugar content, use 2 ounces of juice. Make sure you use good bottles made for brewing.
Core apples and cut into slices. Place apple slices in blender.
Add water and blend on high until apples are liquified.
Place a coffee filter in a strainer and place strainer in a bowl to catch the juices. This only takes about 5 minutes.
Pour the apple juice into the strainer and let strain until all the juice runs through the strainer. You can use the leftover apple bits to make apple butter and it also works great in muffins or scones as a substitute for oil.
Remove the juice to use in the water kefir.
Apple Water Kefir
Place 14 ounces of water kefir in each of your 16-ounce bottles.(Make sure you use bottles such as Grolsch or Bormioli thick glass bottles. Bottles bought at craft stores can explode.)
Add 2 ounces of freshly squeezed apple juice to each bottle. Seal your bottles.
This second-fermented Water Kefir only needs to sit 1-3 days or until it becomes bubbly. Check it often by opening it to see if it is bubbly. (Warmer homes take less time)
Once ready, you can drink or refrigerate for storing. (Drink within 1 week for optimal flavor and benefits.)