Many people say a prayer of thanks before every meal; in the Roman Catholic faith, this prayer is called "grace"; it is a name for any of a number of short prayers recited aloud or inwardly before or after eating. Before eating, Catholics recite this prayer:
Let us pray. Bless us, O Lord, and these, Thy/Your gifts, which we are about to receive from Thy/Your bounty. Through Christ, our Lord. Amen.( This prayer is preceded and followed by the Sign of the Cross.)
After the meal, Catholics often recite this concluding prayer:
We give Thee/You thanks, Almighty God, for all Thy benefits, and for the poor souls of the faithful departed, through the mercy of God, may they rest in peace. Amen. (This prayer also is preceded and followed by the Sign of the Cross.)
A more universal Christian prayer before a meal is as follows:
God is great, God is good. Let us thank Him for our food. Amen.
Often, too, many Christian homes and institutions add thoughts of thanksgiving that are relevant to for day of event for which they have come together to "break bread."
For Muslims, however, giving thanks is not a communal prayer, but an individual one as a reminder that each individual comes into world alone and departs alone.
In the Jewish faith, a meal is only that in which bread is literally broken. Then, after the meal a series of four benedictions are said, involving blessings.
Honestly, as a Christian student at a Christian school, my peers and I give thanks every morning for just "waking us up this morning." I don't really believe that there are specific types of prayers that require the perfect moment to recite. As advocated in the Bible, praying is a way to grow closer to God and honor him. Theoretically every time you pray you are giving thanks to God in an indirect way. Praying also isn't about just reciting a written prayer such as the Lord's Prayer (not like it doesn't have meaning). I used to believe the only way to give thanks and honor God was through reciting specific prayers but after renewing my faith, I've come to the conclusion in my personal life that praying is just a way to thank god for what you are grateful for and a way to just talk to your Heavely Father.