What should I choose, food processing at NIT Rourkela or a drop after Advanced?

The answer to this depends upon your purpose of getting into NIT Rourkela. If exposure is the reason, you will get plenty at NIT R. But you will have to be proactive all the time. However, exposure is surely not your first priority.

Good placements are usually the prime reason for students to seek admission into top IITs and NITs. To be honest, the Food Processing Department at NIT Rourkela is not well established. Your food processing department tag will limit your placement options, even at an institute like NIT Rourkela. You will be eligible to sit for the placements of a handful of companies like TCS, INFY, IBM, WIPRO, etc. Hardly any food processing companies visit the campus for placements. But with the right skill set and an NIT Rourkela tag, you may end up with a good off-campus offer. However, you will most probably end up in Analytics, Big Data, or IT.

If you are confident enough, have a passionate interest in other branches like CSE, Electrical or ECE and know your calling, I would recommend you to take a drop. Whichever option you choose, remember that if you are skilled in your field, you will get placed in a good company, sooner or later.