I've learned from the Japanese phrase 'itadakimasu,' which is said before eating as a way to thank the person that prepared the food. I think in the west, a lot of us grew up learning to say things like grace before a meal, but that is too religious for me and gives God credit for peoples' hard work instead. I love the idea of ritualistically thanking the people who actually made the food. It was one of the things I appreciated while studying there that has stuck with me.
In my culture its common courtesy to thank a person after the meal, either the one who made it, brought it, or paid for it. But only if they're present. It ain't a ritual. Same-ish thing.