I hope you beat him to a pulp for that remark alone. ;o)
It was a business function, and others were present and listening.
Despite that, I shocked myself by presenting him a dead-serious "Seig Heil". He got the message.
He was making these anti-Semetic comments as if it was common, day-to-day conversation - not one iota of embarrassment - so I presume it is exactly that in Germany.