Does he like grape juice? I just made the grape cooler (called "new wine" in the maker's diet"), and it was very good.
I used one litre (quart) of juice, 1 teaspoon of Sea Salt , and 2 Tablespoons of whey. Put all ingredients into a glass bowl, cover loosely and let sit for 3 days. Skim the scum off the top and refrigerate. It's supposed to improve with age, but I liked it so much I don't think it's going to get very old!