So when cap was in Dimention Z he spent 10 years there and when he came back only 30 minutes or so has passed in this reality. So when he came back was de-aged to the point just before he entered the other Dimention or when he was in Dimention Z did he not age at all.
No, it says clearly in the issue after dimension Z that the SSS keeps him from aging or at least suppresses much like Nick Fury's infinity formula.
Basically the Super-Soldier Serum causes his cells to not break down as quickly as normal humans, therefore he ages slower than a normal person would. Steve did spend 12 years in Dimension Z and is currently 102 years old (as he was 90 when he first entered Dimension Z), but physically his body has only aged maybe half that time thanks to the effects of the SSS.