A bottles life expectancy?

I've opened a few bottles of my latest batch of Blonde and there is so little head you could probably get away with saying none. There's also no lacing. Weird thing is, if I use the same glass for the next bottle there's more head, but still no lacing.

Someone on another site mentioned they only use their bottle a couple of times and then trash them. I use PET bottles, and I've been using the same ones for probably a dozen batches. I rinse them after using, and then again before sanitizing, but now I'm wondering if I've used them to their maximum efficiency?

Ideas?

If the head changes from bottle to bottle, it's probably your glass. Dishwasher soaps contain chemicals to prevent waterspots. They also discourage the head on your beer. Try rinsing your glass with hot water only, no soap, between uses.
I don't know the life of a PET bottle, I use glass.

The guys on the Cooper's forums,for instance,say that the screw on caps used on the PET beer bottles are good for 5 or 6 uses. Then you need new ones. They also,as I found early on,need to be screwed on surprisingly tight to maintain a good seal while carbonating. That said,it's dissolved protiens in the beer that form the head,which is driven by carbonation in the glass.

I'm inclined to agree that it's your glasswear. The second beer heads better because the first beer washed the detergent residue off.

I had a similar problem several months ago, which, at first, seemed to be uneven carbonation from bottle to bottle. I had not g-e-n-t-l-y stirred the beer and priming sugar before bottling, so some of the problem was due to slightly uneven carbonation. However, once I THOROUGHLY scrubbed my favorite beer mug with water and table salt, I cured the problem! The salt is abrasive enough to remove the film that builds up on the surface of the glass from repeated washings. Now, I simply rinse my favorite mug with hot water after using it.

glenn514