Disclosed are methods and system for reducing or eliminating the possibility of cross-contamination between food to be cooked in a cooking device and food cooking in the cooking device. The methods and systems determine the placement into a cooking device of food product to be cooked by the distance sensor, determine a hygienic safe cooking time (HSCT) for that product based on the identification of food product to be cooked, and compare the HSCT to one or more remaining cooking times of food product cooking in the cooking device on levels below and/or above the desired placement of the food product to be cooked. Various methods of identifying the food to be cooked may be employed, both manual and automatic. As a result of the comparison, the methods and systems of the disclosure can identify safe carrier/tray level(s) for accepting placement of the food to be cooked.
