Rice cookers are kitchen appliances and are used in kitchen environments. White plastic will be stained in an oily fume environment, which is a normal physical reaction phenomenon.
There are two main reasons for the discoloration of rice cookers:
1. Food color penetration: When using a rice cooker for cook dishes, certain foods, especially those rich in natural pigments (such as red pepper powder, beetroot powder, soy sauce, etc.) or artificial pigments, will slightly penetrate the plastic parts on the edge of the rice cooker inner pot through steam or direct contact during long-term high-temperature cooking, causing staining;
2. Incomplete cleaning: After long-term use, if the inside of the rice cooker is not cleaned promptly and thoroughly, especially the joints between the inner pot and the plastic parts, the remaining food residues will attract and solidify the pigments. The temperature inside the rice cooker rises when cooking, which will accelerate the penetration and fixation of the pigments in the remaining ingredients, resulting in staining. This phenomenon is normal, especially when cooking ingredients with strong pigments.