It can also be used to loosen baked and dried-on food soils by soaking or pretreating with it prior to automatic dishwashing. It must produce little or no suds or foam because too much foam can inhibit the washing action. Its important functions include the following:
- Tie up water hardness minerals to permit the detergent to do its cleaning job.
- Make water wetter (reduce surface tension) to penetrate and loosen soil.
- Emulsify greasy or oily soil.
- Remove proteinaceous and starchy soils.
- Suppress foam caused by protein soils such as egg and milk.
- Help water to sheet off surfaces, thus minimizing water spots.
- Protect china patterns and metals from the corrosive effects of heat and water alone.
- Surfactant – lowers the surface tension of water so that it will more quickly wet out the surfaces and the soils, thus allowing water to sheet off dishes and not dry in spots. The surfactant also helps remove and emulsify fatty soils like butter and cooking fat. Surfactants having low sudsing characteristics are used.
- Builder (complex phosphates) – combines with water hardness minerals (primarily calcium and magnesium) and holds them in solution so that the minerals cannot combine with food soils and so that neither the minerals themselves nor the mineral/food soil combination will leave insoluble spots or film on dishes.
- Alkaline buffers and water softeners (sodium carbonate) – help break down and help remove proteinaceous and starchy soils.
- Corrosion inhibitor (sodium silicate) – help protect dishwasher parts, prevent the removal of china patterns, and the corrosion of metals such as aluminum.
- Fragrance (optional) – covers the chemical odor of the base product and stale food odors.
- Oxidizing agent – helps break down protein soils like egg and milk, aids in removing such stains as coffee or tea, and lessens spotting of glassware.
- Processing aids – generally inert materials, water, and thickeners that allow the active ingredients to be combined into a usable form.
- Suds suppressor - controls foam from food soils, especially protein soils.
