I keep learning new stuff about dishwashers. Almost five years ago, I wrote about one misconception of how it worked that got removed when I saw a video taken inside one while it was operating. Now this article tells me that my practice of pre-rinsing before putting items in the dishwasher is not only wasteful of water, it actually leads to less clean dishes!
One of the arguments against pre-rinsing is that certain detergents are designed to cling to food particles, as the Cascade detergent brand informed The Wall Street Journal in 2015. Without a surface to stick to, your dishes won’t get as squeaky clean.
Consumer Reports offers another explanation. According to the product-testing magazine, newer dishwashers—those purchased within the last five years or so—won’t wash your dishes for very long if the sensors in the machine don’t detect much dirt in the water. “When that happens, the dishwasher gives them just a light wash, and items come out less than sparkling,” Consumer Reports’s Ed Perratore wrote in 2016. “To avoid that lackluster result, don’t rinse; just scrape off bits of loose food.”
Sure, you can still scrape off big chunks of excess food or soak your egg yolk-stained plates in hot water first, but there’s no reason to rinse every single item before loading your dishwasher.
This advice seems so counter-intuitive but Consumer Reports is a pretty reliable source of information.
Surveys have found that Hispanic and Asian families tend to view using dishwashers as a sign of decadence, that people who use them look down on the honest toil of washing dishes by hand. In fact, it is not common for many of those households to use the dishwashers that are already installed as storage places for their hand-washed dishes.
The more thrifty among them also justify avoiding them with the argument that it is wasteful of water. That turns out to be another big misconception.
One mind-blogging statistic from Consumer Reports states that the average person wastes 6000 gallons of water a year by pre-rinsing. Most dishwasher machines use just 3 to 5 gallons of water per load, while the average person uses about 27 gallons when washing dishes by hand, according to The National Resource Defense Council.
That’s a huge savings of water.