For the purpose of administering the terms of this Part, each dealer shall deduct from the over-order rate otherwise to be paid to producers and cooperative associations (except a cooperative which has arranged to make the reports and payments with respect to the milk of producers) an amount to be determined by the commissioner but not to exceed $.05 per hundredweight, on all pool milk received from producers to be paid to the commissioner, as trustee. Such funds shall not be deemed to be State funds.