prejudice (one) against (someone or something)
To cause one to have a prejudicial and unfavorable opinion of someone or something. Don't let one bad experience prejudice you against trying snowboarding again! You shouldn't let her former employers' reputation prejudice you against her—she would make a valuable addition to your team.
prejudice someone or something against someone or something
to turn someone or a group against someone or something. I believe that the lawyer was trying to prejudice the jury against the defendant. The discussion about how calves are raised prejudiced me against eating veal.