Juice from 6 lemons or 5 lemons and 2 oranges
lemon zest (I used it from all the lemons because I like it that way!)
8 cups sugar
6 cups boiling water
1/8 cup tartaric acid
1/4 cup citric acid
2 tbsp epson salts
Dissolve the sugar in the boiling water (I sometimes go a little easier on the sugar because I like mine a little less sweet). Cool and add all the other ingredients.It keeps in the fridge for a long time. To drink it, just put about an inch of concentrate in the bottom of a tall glass and fill it up with cold water. Adjust to your liking.Just some more info about the above recipe...Tartaric acid and Citric acid are white powders. I've made it without tartaric acid before, but you really need the citric acid for the recipe to work. I have trouble finding these things here, but where I ended up getting them was the PHARMACY of all places! In a small bottle. It says right on the side of the bottle "good for use in lemonade" so I'm not sure why they sell it at the pharmacy, but oh well!I also since was able to order in citric acid from a local bulk food place. He had to special order it which meant I had to buy the entire 2 or 3 kg bag, which was the smallest quantity he could order! I don't have to buy it ever again.