Disclosed is a cooking apparatus including an image capturer for obtaining an image of food located in the cooking apparatus, a memory, and a processor configured to execute the instructions to cause the cooking apparatus to: obtain an image through the image capturer; obtain contamination level information according to a plurality of contamination detection techniques for detecting contamination of the image capturer based on the obtained image; identify a weight of the contamination level information based on at least one of a type of food or a cooking phase; obtain final contamination level information based on the contamination level information and the weight; and identify a contamination level of the image capturer based on the final contamination level information.