Sahih Bukhari Volume 3, Book 47, Hadith Number 753.

Narated By Um ‘Atiyya : Once the Prophet went to ‘Aisha and asked her whether she had something (to eat). She said that she had nothing except the mutton which Um ‘Atiyya had sent to (Buraira) in charity. The Prophet said that it had reached its destination (i.e. it is no longer an object of charity.)