Aluminum, specifically bare or uncoated aluminum, is generally not recommended to be put in the dishwasher due to a few reasons:
Discoloration: Aluminum can react with certain detergents or chemicals present in dishwasher detergents, causing discoloration or staining. This can result in a dulling or darkening of the aluminum surface, affecting its appearance.
Corrosion: Aluminum is a reactive metal, and prolonged exposure to the hot water, high heat, and harsh chemicals used in dishwashers can cause it to corrode. This can lead to pitting or damage to the aluminum surface over time.
Fragility: Aluminum cookware or utensils, especially those with thin or delicate construction, may not be able to withstand the forceful water jets and movements inside a dishwasher. This can cause warping, bending, or deformation of the aluminum items.
While some aluminum items may be labeled as dishwasher safe, it's generally recommended to hand wash them to preserve their appearance and longevity. If you are unsure about the dishwasher compatibility of your aluminum cookware or utensils, it's best to refer to the manufacturer's instructions or guidelines to ensure proper care and maintenance.