The surface will not be sterile. Informal public health standards accept 100 microorganisms per 8 square inches of food contact surfaces as safe. Chemical sanitizers are very sensitive to organic matter and if the surface is not clean, chemicals will not be effective in reaching the microorganisms on the surface and inactivating them. Some bacterial cells have the ability to form spores. The spore state is a period of no growth, similar to hibernation, in which the cell dries up and the cell wall becomes thickened.
Spores are very resistant to heat and chemicals.
The reduction of all multiplying vegetative microorganisms and dormant but viable spores to a safe level. This is the process used to create room temperature-stable canned food. In contrast to the dormant spore, which has no metabolic activity until activated when food is cooked, the vegetative cell is in an active metabolic state in which the bacteria are growing and multiplying at a rate depending on the food temperature, acidity, water, additives, etc. References Canada, J.C., Dryer, J.M., and Mauder, D.J. 1979. Test for commercial sterility.