Real ramen heads don't give a crap about slurping, and many Japanese ramen chefs consider slurping to be a compliment, but if you're forced to eat ramen around people who don't appreciate a good slurp you may need to eat quietly.
Or better yet grab one of these "Otohiko" noise canceling noodle forks and slurp away with impunity! The Otohiko noodle fork was created by Nissin to battle "noodle harassment" by drowning out the sound of slurping with music:
Do you know an international issue “Noodle Harassment”? People say that the slurping noise Japanese people make when they eat noodles makes people from abroad uncomfortable. …The moment that the high powered directional mic equipped on the fork detects the sound of noodles slurping, it transmits that signal to a dedicated app installed on a smartphone, using short wave radio communication. Sound is then emitted from the smartphone to camouflage the noodle slurping noise.
-Via Laughing Squid