what is the use of using nisin as preservative for paneer?

Question

any other preservative can we use instead of salt?

Answer 1

To find out what Nisin is and what it does, look here: http://en.wikipedia.org/wiki/Nisin



There are heaps of other preservatives available. Are you asking specifically about preserving cheese or food in general? Either way, I hope these websites are helpful:

http://en.wikipedia.org/wiki/Food_preservation

http://en.wikipedia.org/wiki/Preservative



Or, this specific websites about a cheese preservative called Natamycin:

http://en.wikipedia.org/wiki/Natamycin