Every dealer in agricultural products must upon the receipt of agricultural products on consignment basis and as he handles and disposes of them, make and preserve for at least one year a record, specifying the name and address of the producer consigning the agricultural products, the date of receipt, and the kind and quality of such produce. Such consignment sales must be substantiated by a written contract on forms approved by the Department of Agriculture. The dealer must make payment in settlement for such shipment to the producer within ten days after the sale of such agricultural products, unless otherwise agreed in writing.