Is security work frowned upon by law enforcement?

No. Many people that want to become police officers do security jobs, and many police officers have done or do security jobs. If you want to get a security job, get one if you can. Just keep a good record and reputation. That is very important. Whatever job you have or get, be a good employee so that you get a good reference. Any job that can improve your communication and people skills would be good to consider if you want to become a police officer. It is great that you are in college. Getting a college degree is one of the best things that you can do if you want to become a police officer. Make the most of your time and money. Get the highest grade point average that you can, participate in a couple extracurricular activities, get a good internship, do some regular volunteer work, don't do anything illegal, and maintain a good reputation. Best of luck!

Security work is fine if you have the right attitude.

The main thing is to know the difference between a security guard and a cop. Security guards observe and report the situation in an area that they're guarding. As a general rule of thumb, you do not get physically involved in a situation unless its self defense or someone's life is in danger. Non-Commissioned security guards are unarmed and have no arresting authority beyond that of a private citizen. Commissioned security guards may have arresting authority, but it depends on state laws and company policies. If you know you're roll as a security guard, you'll do fine. If you act like a wanna-be cop, you've have trouble and peeve off a bunch of real cops.

A security background can be helpful, because security guards often work closely with police. There are similarities in the jobs. Both make patrols, both use radios to report their status, both do a lot of documentation through logbooks and incident reports.

Its a job. Nothing more, nothing less. It's going to help you pay your bills but it's not really going to give you a leg up on a police job.