made a bad guy move

Brought gallon of milk to event, one thing led to another & now all the brothers think I can lactate. don't mind this reputation but in the thrill of the moment I spilt the gallon of (rotten) milk on rush chair (its not an actual chair)

now he thinks I spilt my lactated milk all over him.
even worse, he thinks I lactate rotten milk when its actually some of the freshest

how do I convince him my milk is fresh?
my bid is riding on this, anything helps