It depends on what Pokemon u use it on, the nature of the Pokemon, the Flavour & mildness of the juice, and what apricots u used.
Personally, i always use... let's say, I want to raise My PKMN's Power, I put in a Red Apricorn (which raises Pow.) and 4 Black Apricots (to increase Flavour), then I go up and down the bycicle Road around 15 times to max out it's mildness, and feed it to 2 PKMN who needs Power, then add another black apricorn and repeat.