Hello Priyanka, 

This is good query which many people come across, bio technology as under graduation will help you to reach various zones in that domain. But sticking to food and nutrition will restrict you to limited set of oppurtunities, here I am not degrading doing Food and Nutrition course. I am just highlighting the consequenses which you might go through in future. 

When your main focus comes to placement there is end for opening in any stream, its just we have to figure ways to reach out those oppurtunities.Reach out people who are exiting in that stream and ask ideas.

While doing your ug/pg course, try to recognize good reputed companies and develop contacts with many ideas like using your alumini, linkedin, indeed, etc. Then take up implant trainings and internships through which get to know your domain well.  

The ultimate goal of any degree is to be placed well in a good and reputed company, irrespective of the degree is from private college or public college. 

Ultimately what matters during placement is your skills and knowledge about your field. So it's better to focus on the knowledge and skills rather than the college type.