We test stain removers, including “laundry soaker” powders, as spot treatments.
With powders, we mix 30g with 90ml of water to make a paste. We also test how well stain removers compare to washing with:
water (no detergent)
a paste made from 30g of a mid-performing laundry detergent mixed
with 90ml of water.
We use cotton material swatches stained with substances including ground nut oil (to simulate everyday grime), grass and mud, olive oil, and chocolate ice cream.
Before washing, our experts apply a set amount of each stain remover to the stained swatch and let it sit for five minutes.
We use a front loader on a cold wash cycle with a mid-performing powder from our [laundry detergents test][1].
Following the wash cycle, we measure the degree of stain removal. The stains need to be tough to show up differences in product performance, so the scores are an indication of each product’s relative performance, not a measure of the amount of soil removed from our test swatch. At home, you can expect pre-treaters to remove more of each stain, especially if you get to them quickly.
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