There actually is! I'm not sure if this works for platinum but I heard someone say it on another question. If you give shuckle an oran berry and it doesn't consume it fro a while then it will turn into berry juice. If you give shuckle a berry juice and it doesn't consume it and you wait for a LONG time then it will harden into a rare candy.
NOTE: I'm not sure if this works for platinum. Someone told me.