I think there are two ways to interpret this question, not sure which one you meant.
Question one: if you don't remember being conscious, were you actually conscious?
Seems the answer should be yes. Just because you don't remember something doesn't mean it didn't happen.
Question two: can you be conscious without something like memory?
This one I think may depend on future understanding of what consciousness is. It seems like consciousness without any memory would be consciousness without anything like perception.