What is to be done to expiate the sin of perjury by swearing on the Holy Qur'an not to eat a certain type of fruit, and is an oath concerning food invalid?

Swearing by the Mus'haf (Quran) is a binding oath that requires expiation (kaffarah) if broken, because it is the word of Allah Almighty, and His word is one of His attributes. If the intention behind swearing by the Mus'haf was to make an oath, then it is binding and expiation is required if it is broken. However, if it was merely words uttered unintentionally (laghw oath), then there is no expiation for it, as Allah Almighty says: "Allah will not impose blame upon you for what is unintentional in your oaths, but He will impose blame upon you for what you intended of oaths." (Al-Ma'idah: 89).

The expiation mentioned in the Quran is: "the feeding of ten needy people from the average of that which you feed your [own] families, or clothing them, or freeing a slave. But whoever finds not [the means] - then a fast of three days." (Al-Ma'idah: 89). Breaking an oath is not an act of disobedience in itself; rather, it may be obligatory or recommended if the oath was to refrain from an obligation or a recommended act. The Prophet, peace and blessings be upon him, said: "Whoever takes an oath and then sees something better than it, let him do that which is better and offer expiation for his oath."