Regular diarrhoea and bloating. Ppis.

I am staying at a government hostel at a college for higher studies where the mess food is contaminated and we have no other option. I got LFT, USG, KFT and other tests done, everything is normal and is checked by doctor. Every night after eating food at the mess i feel bloating, even though I walk after every meal, and after few hours watery motions happen like diarrhoea. It's happening everyday as the food quality is bad. Is there any medicine or way in which I can protect my intestine and stomach even after eating this food. I have already consumed more than 3 strips of bifilac cap in a month and still struggling. Same issue with fellow hostel mates. Any syrup or medicine which can be gastroprotective in nature, other than ppis.