In 44:25 we find Yosef sending the brothers back home to get Binyamin. When he does, he fills their sacks with food.
Yosef is in the middle of a hostile encounter with them, accusing them of being spies and liars. He just locked one of them up to gaurantee the brothers would return with Binyamin in order to obtain the release of their imprisoned brother. And he gives them the food they want? he should have sent them home and told them to come right back and he should not have given them anything!
Even in a hostile situation, like this one, you should not back your opponent into a corner and not leave him any options. If Yosef would send them home without offering them anything, maybe they would have returned with an army to wage war. Yosef calmed them down by giving them the food even though they were in the middle of a hostile encounter. That practically gauranteed that they would remain fairly docile and not do anything to jeopardize things.