I have done over 4000 km in Indian trains over the last six weeks. I have not had one single problem with the food bought from the official IRCTC stands or guys going around. Look out for people with uniform shirts.
Some of the food was actually excellent
If you are travelling around India, do not book an air con train, they are far too cold. I have done over 2000km on the train system ad I recommend the no air con. Also the in the air con you keep the windows closed, and they are filthy so you don't see anything
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