The best sour mix is made from a mixture of fresh lemon juice, sugar and water
with a little egg white thrown in for good luck. I would recommend the
following proportions for 1 litre of mix:
400ml Sugar syrup (sugar dissolved into hot water)
600mls Fresh lemon juice
2 egg whites
Shake mix container before use (1 litre is enough for 20 - 30 cocktails)
Happy mixing