The protestant christian world is quite used to prayer before main meal consumption. This is not necessarily a useless ritual, but it probably is. Any moment is appropriate for a comment of our thanks to God for His intervention in our lives, but if the prayer attempts to invoke or request God's special care for our food so that we don't die from its potential toxins, then the prayer is misguided.
ALL of our prayers are thanksgiving. I suppose that the feeble human spirit will also occasionally express to God anguish for earthly events. However, requests for God's specific action deny many things that God has already said He would do, or has already done. God knows what needs His intervention, and we can rely on His word above all else. Sometimes I think we have more faith in the electric company than in God to act.
The presence of food in the kitchen already strongly suggests that God has already blessed His children.
Those who feel the need to ask for another "blessing" on the food so that it will take on magical powers and "be used" in those who eat it can remember that christians already have every blessing God ever could give us in the gift of the abiding presence of the Holy Spirit.
