Abstract: The development of e-commerce has changed sales model of fresh food. Many suppliers not only wholesale their production to retailers, but also sale to customer on the internet directly. Coexistence of online and offline channels is popular in fresh food market recently. The relation between supplier and retailer includes completion and cooperation. In addition, fresh food is perishable and the quality which influenced demand is varied with time and temperature. So coordination between dual channels is difficult but very important in fresh food supply chain.
Fresh degree function and market demand function are built in which the factors of time and temperature affecting the quality of fresh food is considered. Coordination problem of mixed channels is studied based on two-echelon supply chain including traditional channel of a retailer and online channel of a supplier. Then, decisions making strategies are explored by Stackelberg game and Bertrand game under the decentralized situation. And the change of the equilibrium strategies is discussed under centralized situation. Next, the coordination mechanisms of joint contracts with revenue sharing contract, cost sharing contract and the wholesale price discount contract are designed. Through designing the reasonable parameters of contracts, the coordination between traditional channel and online channel can be realized. Finally, a numerical example verifies that the joint contract can make the profit of supply chain get Pareto improvement. Also, the relationships among supplier optimal profit, consumer acceptance index and temperature are demonstrated. The influence of consumer acceptance index on the joint contract optimal parameter is analyzed in the case. These results can help fresh food managers on how to design contract to coordinate the dual channel supply chain.

Key words: fresh food, supply chain, dual channel coordination, time and temperature