My goal is create realistic foam. I mean really realistic foam with bubbles, no only SSS shader and done :-).
Use particle system's is not enough, because bubbles overlaps and black artifact's appear.
Any ideas? Some reference images and something about bubbles:
http://www.exploratorium.edu/ronh/bubbles/bubble_meets_bubble.html
EDIT: I want this for 360° turntable animation. Bubbles and foam does not to be animated, but should be good keep reasonable render time.
Of course, if someone know how to make it animated I glad to learn it and I'm sure I'm not only one. But my priority is realistic look, not animation.
Only for clarification: I don't need to know how to make bubbles in beer (there is very good tutorial by Andy Price), please focus only on foam. Beer is not important.