We get feedback from folks who buy our laundry soap- here's a recent one from our Etsy shop:
"Garden scent smells lovely. Works great on everything but urine (potty training toddlers is messy business)."
When we get this kind of feedback I know that the person has an HE machine, a high efficiency model that uses less water than traditional top loading machines. The problem isn't the soap, it's the small amount of water! Quite often HE machines just don't use enough water to do a thorough job.
I wrote back to our customer:
"Thanks for your feedback! If you're still getting a urine smell after washing, try running the clothes through a cold water wash with no soap first, then washing as usual with detergent. Just like you would with cloth diapers. There can be a lot of urine in training pants, and one run through, especially in an HE washer with the low water level, may not dilute the urine enough to get everything out."
She tried it, here's what she had to say:
"That's a good point. I hadn't thought about the HE machine making a difference. You were right. I ran a comparison test using Method just to be sure. And it was the same result with both detergents. It turns out that just adding an extra rinse or tweaking the soil level setting on the HE machine did the trick and got the smells out; both urine and work smells."
The cloth diapers of today are super absorbent. With the small amount of water in an HE machine, much of that water is simply absorbed by the diapers, right along with a LOT of urine. To get diapers really clean, a rinse is needed first before the wash.
The same can be true for other heavily soiled laundry, people will write to me trying to get body odor smells out of clothing. Try the extra rinse, or simply add an extra bucket of water in the washer along with the clothing before running the cycle. You have to have water to clean thoroughly, try this and see for yourself. =0)