from early morning to night you will always get something to eat by caterers or local vendors. food provided by caterers is good in quantity. but taste is bland. it would be fine for old people but for others ask for salt. For mineral water, ask the caterers they sell "Bisleri" and many other brands.
Avoid "Egg Biryani" onboard and in stations, anywhere (its neither biryani nor even tomato rice - just colored bland rice with 2 eggs) . Vendors where pushing "Egg biryani" in Chennai Central at morning 6:30 AM (!???!!!!)
Packed...
more... food in plastic trays (meals like egg rice, fish rice, chicken rice) are available in Malda Town for dinner and Brahmapur for lunch which are cheap and tastier as well.