How to tell if an olive oil can is completely dry?

1. Visual Inspection
Turning the can upside down or tilting it, inspect the interior for water droplets or a reflective film. A completely dry glass or metal can should have a uniform matte finish and be free of any residual water stains.
2. Touch Test
Using a clean finger or a paper towel, gently touch the inside of the can. If it feels moist or sticky, it's not completely dry. A dry can should feel clean and free of residue.
3. Paper Towel Test
Roll a dry paper towel into a strip and insert it into the can, rotating it before removing it. If the paper towel shows no signs of moisture, the can is dry. If it becomes soft or discolored, continue drying.
4. Time and Ventilation
After disinfection, drain the can upside down for 2-3 hours. Place it in a well-ventilated area (such as a windowsill) to accelerate evaporation. Metal cans can be dried using a hair dryer on the cold setting, but avoid excessive heat that may cause deformation.