Laws that took effect in 16 states on July 1 limit phosphorus in household dishwasher detergents to 0.5 percent. Previous products could contain up to 8.7 percent. As a result, major manufacturers have reformulated their products for the entire United States.

Phosphorus in the form of phosphates help dishwasher detergents clean but also boost algae growth in freshwater, threatening other plants and fish. Soaps for washing dishes by hand are phosphate-free, and phosphates have been limited in laundry detergents since 1994.

Early efforts at limiting phosphates left some residents of affected states smuggling higher-phosphate detergents into their homes. Consumer Reports found that the handful of low-phosphate products it tested for its last dishwasher-detergent report tended to perform worst overall.

In CR’s latest tests, all 24 detergents tested were low- or no-phosphate, and there’s better news: Although none equaled the excellent (but now discontinued) product that topped CR’s ratings in August 2009, several were very good.

CR’s testers smeared dishware with a mix of 17 foods (pots got a mac-and-cheese blend) and then baked on the foods and cleaned the items in identical dishwashers to assess how each detergent performed.

Finish Quantum topped the Ratings, followed by Finish Powerball Tabs a CR Best Buy at (22 cents per load), which scored Excellent for dishes and pots, and bested some detergents that cost more.

Cascade Complete All In 1 and Cascade with Dawn ActionPacs (both earned a score of Very Good in CR’s tests, but all Cascades, like all Finish products, aren’t equal. Other Cascade and Finish products were scattered throughout the Ratings.

CR also tested Martha Stewart Clean liquid detergent which would have been lowest-rated of all, but the company said it has since changed it formula.

CR also found:

• Bleach made little difference. Top-rated Finish Quantum has chlorine bleach, but most of the top performers have no bleach. It didn’t seem to act on baked-on soils, but bleach might help with tea or similar stains.

• Enzymes might help. Most of the tested detergents have enzymes, which can break up food for easier removal. Of the five with no enzymes, four were only fair overall; the fifth, Cascade Complete All in One with Bleach Hydroclean, was good.

• Types might not be a tipoff. In CR’s recent tests, tablets and pacs tended to score high and gels low, but it’s too soon to say whether that trend will continue.

• All Cascades aren’t equal. Don’t just buy by brand. Cascade and Finish products were scattered throughout the Ratings.

• Quantumatic isn’t worth the price. A canister that dispenses 12 doses from a cartridge automatically, Finish Quantumatic lets you avoid pouring detergent repeatedly. It performed well but takes up space in the dishwasher and costs about $10 for the dispenser and first cartridge.

• Bottom line. There are several very good products from which to choose. Finish Powerball tablets are least expensive, at just 22 cents per load, and bested some detergents that cost more.

Advanced appliances

Hoping to lure you back into stores, manufacturers are creating appliances that save you time, cut energy use, or make cooking and cleaning a bit easier. Here are several innovations that caught CR’s eye:

• Energy-savers. Smart appliances receive signals from the utility company, alerting you when costs are lowest and reducing energy by adjusting their cycle.

• The induction deduction. Induction technology makes for the fastest surface heating in ranges and cooktops. When CR heated pots of water, induction models were usually 25 percent faster than regular smoothtops.

• Dialing away washer woes. Picture this: You push a button on the washer, dial a service center, and hold the phone next to the button. The washer beeps a code, then the service center diagnoses the problem and maybe even fixes it.