I learned from my mother, who was in the textile business for years, to never wash my whites in bleach and hot water due to the yellowing effect. I have to say that I have done my own bit of research on this over the years and have found my mother’s advise to be accurate. Every person that I have ever known to wash their whites in bleach and hot water had a slight yellowish ting. While their whites seemed white when held up against my whites, that are only washed in cold water and bleach, their whites no longer appeared white. I also learned from my mother that it is not the water temperature that washes the clothes but the detergent that you wash them in. Does The Clorox Company run test to see what water temperature is best for keeping whites their whitest?
Clorox does lots of testing to develop and improve its products, as well as determine the label instructions for the product packages. We test a variety of stains and soils for cleaning, as well as whitening and brightening. In addition, we test how our products work with different detergents, clothes washer designs, and in different water temperatures. That’s because there are three different forms of energy that accomplish cleaning and whitening: thermal (water temp), chemical (detergent/bleach), and physical (agitation). Your personal experience doesn’t match our laboratory test results based on average consumer wash conditions—all other variables being equal, we typically see improved cleaning and whitening in hotter water. It’s hard for me to know exactly how you do your laundry, and what differences exist between your wash habits and your friends’, but here are some thoughts on why you find your whites even whiter than your friends’ whites:
It sounds to me like you are a very conscientious bleach user, and I am not surprised you get such good results. For most people, using hot water is important to get the best results possible. But by carefully controlling the other variables, one can wash in cold water and get outstanding results, as you have found.