It’s good to know how to make your own rejuvelac. It’s available commercially in some stores, but it’s not cheap, and usually it’s made with wheat. For those who can’t or don’t want to spend the money ($8/quart) or have a gluten intolerance (and therefore don’t want to risk rejuvelac made from wheat or rye berries), making it at home is important.
It’s not difficult, especially if you soak, sprout and dehydrate your grains routinely (like I do) and always have sprouted grains on hand.
Just blend the sprouted grains in water long enough to crack them (a few seconds, maybe 10). For a gallon of rejuvelac, I start with 3/4 cups of sprouted grains and 4 cups of water in the blender. I pour the cracked grains into a gallon jar and fill the rest of the jar up with purified water. I place a cheese cloth over the top and let sit for a few days (upto 5). I skim off the gross stuff that will form on the top and then strain through a cheese cloth or milk bag. Stores well in the refrigerator for weeks (even a few months).
Do your research about the process so that you feel comfortable. If you’re worried that you’ll poison yourself because you’ve made a mistake, you might never do it and miss out on the benefits.