What is the expiation for swearing to one's mother not to eat a specific food, which resulted in depriving the son of a beneficial food, so that the son may return to it?

The expiation for an oath is feeding ten poor people from the average of what you feed your families, or clothing them, or freeing a slave. And whoever cannot find [the means], then [it is] fasting for three days. The value of the feeding is to be given to the poor and needy, or to charitable organizations, with a clear explanation that it is expiation for an oath.