Sunday, March 29, 2009

The Great Laundry Experiment

A few posts ago, I suggested that it might be interesting to create a unit study around the current economic headlines. Under the heading of science, I mentioned comparing a name brand laundry soap with one of the homemade varieties being mentioned more and more often on the frugal websites. Anyway, I thought I would follow up with the results of our own laundry detergent experiments.

We compared three liquid detergents. I actually prefer dry soap, but the majority of the recipes I located were for liquid soap. We used liquid Tide with Bleach, since that is my usual soap of choice, an inexpensive generic brand, and a homemade version. The recipe we followed contained borax, washing soda, a bar of laundry soap, and water.

The first step in our experiment was to create a test cloth. We used an old pillow case, and stained it with coffee, jelly, mustard, ketchup, marker and grass.

The children enjoyed this step quite a bit, even if I thought it felt a little Brady Bunchy.

We washed the stained pillow case with Tide in hot water, using a little of the detergent as a pretreater. Then we stained the cloth on the other side with the same configuration of stains, and washed it with the generic detergent in hot water, using the detergent to pretreat again. Finally, we stained a remaining fresh spot on the cloth, marked it, and washed it with our homemade detergent, using it as a pretreater too.

The Tide left behind a light mustard and ketchup stain (I'm pretty sure this would not have happened with the powdered version of the soap). The inexpensive brand left behind a more pronounced mustard and ketchup stain, as well as a light coffee and grass stain. The homemade soap left a darker ketchup, mustard and coffee stain, and a light grass stain.

Just for kicks, I threw the pillow case back in to a soak in the washing soda, and then rewashed it with the homemade soap. Almost all of the stains came out. The mustard remained, but it was much lighter.

We concluded that the more expensive soap, does indeed clean better. It might be possible to tinker with the homemade recipe to increase the cleaning power though, while retaining the savings of making it yourself. I had tried almost every detergent on the market before settling on Tide with Bleach as my favorite, I'm willing to give the homemade variety a few more tries before giving up on the savings.

It was an interesting experiment for the children, and I got all my laundry done. Really a win - win scenario. It's not often a science experiment leaves the house cleaner than when we started.

It's great to be a homeschooler!


Serica said...

So, I'm interested...
How much does your homemade laundry detergent cost per load?

LJohnson said...

I'm not sure the actual cost yet, because I'm still tinkering with the recipe. I doesn't matter how cheap the stuff is, if it doesn't clean. With that said, it cost about $8.00 to make our original recipe with almost an entire box of borax, and washing soda left over. If you figure another $1.30 per bar of soap for each additional batch of soap you need (one batch seems to last us about week), your coming out to pennies per load. We will get more scientific about it, and do the math completely, when we're happier with the cleaning results - so far adding a half cup of borax and a half cup of washing soda each load has improved the cleaning, but obviously reduced the savings (there have been some excellent sales on Tide :)