A question about a recipe: Cool Rise Challah

I have a question about step 5 on the recipe "Cool Rise Challah" from Bria. It says:

"Knead 5 to 10 minutes, adding additional flour as needed, until it is smooth, elastic, and passes the windowpane test. Place the dough in a large, lightly oiled bowl, turning it over once to fully coat with oil. Cover with a tea towel and let raise for 20 minutes on the counter. "

What is the windowpane test? thank you!

Cool Rise Overnight Challah
Recipe question for: Cool Rise Overnight Challah


Bria September 29, 2011
Sdebrango's explanation is great. If you need images or video, Google "windowpane test" and you'll get lots of good stuff.
sdebrango September 29, 2011
Hi Hayley: I cut and pasted this from one of boulangere's recipes she is an expert and explains so well:
Pull off a walnut-sized piece of dough, and briefly round it up between your palms. Tenderly begin stretching it over the tips of your fingers. You want to see how thin you can gently stretch it without it tearing. This is called testing for a windowpane. When you get it thin and can also tap gently on the backside, you're there; you've adequately developed the gluten in your flour. It will hold your bread up just like framing and timbers hold up your house. If the dough separates, simply toss the piece of dough back in and continue kneading on low speed for a few minutes more until you build a good windowpane.
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