Extracting Value at the Commerce

3/5 NL game again. I'm dealt 99 in LP. Several limpers ahead of me. I raise to 15. Everyone calls. Pot = 90 Flop is J95 rainbow. Checked to me and I bet 40 doing my best to represent an AK continuation bet. One caller on my right. Pot now 170. Turn is a blank. Villain checks. I do some acting, playing around with a large stack of chips and then check behind. River is another blank. Villain checks to me a again. I "think" for a moment and bet $50. Villain thinks for a about a minute, looks at me and says "I know you have Ace-King." I say nothing and stare at the pot. Villain thinks for another 15-20 seconds and folds. Anything I could have done to induce a call/ bluff raise here? We each had a few hundred more behind. Seems that villain got the exact impression that I was trying to create with my betting but didn't have the guts to bet. After he made the AK comment, I thought about saying something to the effect of "prove it" but decided against it. Is betting the turn a better idea? I put him on a smaller pocket pair since there wasn't much of a draw on the flop.