I see it in mine too.

Probably ingredients that didn't mix properly or masuk angin.

Found this from here http://forum.bodybuilding.com/showthread.php?t=153759061:-

Just received an email from Optimum Nutrition.
-----------------------
Dear Ivan,

Thank you for choosing Optimum Nutrition! Yes, this is completely normal. It is simply amino acid precipitate.

Best of health!

Consumer Affairs Rep 02866
Optimum Nutrition/ABB Performance
-----------------------
i wish i can get my hands on some sample to compare...

edit: are we talking about these?



This post has been edited by aaronpang: Jun 14 2016, 10:33 AM