This article is the archived version of a report that appeared in August 2009 Consumer Reports magazine.
Proposed federal legislation to ban dishwasher detergents containing all but trace amounts of phosphates is designed to help the environment. But many of the eco-friendly products in the latest batch we tested are not great at cleaning dishes.
Detergents without phosphates—which help clean but also boost algae growth in freshwater, threatening fish and other plants—tended to perform worst overall.
The tests were tough: We loaded dishwashers with dishware and pots smeared with a baked-on blend of 17 foods, including rice, macaroni and cheese, chocolate pudding, and peanut butter. Cascade Complete All in 1 packets (with phosphates) were excellent at cleaning, kept washed-off food from being redeposited on dishes, and left no water spots. Five other detergents were very good, including phosphate-free Method Smarty Dish tablets, proving that detergents don't have to contain phosphates to work well. Method's success might be due to the amount and type of its enzymes, which help break up food for easier removal.
Any detergent is apt to clean better if you scrape off heavy soil before loading dishes. (You'll save energy and water if you don't prerinse.) Then take these steps:
The best detergents have phosphates and enzymes, but because manufacturers don't have to list ingredients, you might not know which are which. Our Ratings can help. At 27 cents per load, Cascade Complete All in 1 packets were the standout. Cascade with Extra Bleach Action liquid was also very effective and cost less than half as much. Top performers from past tests include three other Cascades: Complete All in 1 gel, ActionPacs with Dawn, and ActionPacs with Extra Bleach Action. If you'd prefer a detergent without phosphates, choose Method or Simplicity.