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"What difference does altitude make in jam-making?"

Dear Anne and Sue,

When I make my jam, I cook it to 219° F (104° C), but when my friend in Calgary uses the same recipe, the jam fails. Why?

—Submitted by Brian in Victoria

 

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Hi Jim,

"Punching down" is really quite fun -- and certainly a coveted job if you're ever making bread with kids. You do it after the first rising and before shaping. While bread recipes don't always call for punching down, any handling of the dough at this point will cause it to deflate.

To punch down, simply put your fist in the dough and push down on it. You only have to do this once; the dough will deflate instantly. Punching down is a great example of the art of technique and science working together. It accomplishes four things that contribute to a fine loaf of bread:

  • It relieves stress on the gluten (the component that develops elasticity as you knead the dough), which keeps the film around each air bubble from overstretching.
  • It divides air pockets in the dough and so increases the number of gas pockets, which ultimately contributes to the fine texture of your bread.
  • It redistributes the yeast, exposing it to new sources of food within the dough since it will have absorbed most of the food in its immediate vicinity.
  • It evens out temperature and moisture. When yeast ferments, it generates both heat and moisture. You may be surprised at how warm the dough is when your fist is immersed in it!

After you've punched down the dough, most recipes tell you to gather it into a ball and allow it to "proof," or rise, again. The second rising usually takes only half as long as the first.

Have fun with the bread making!
Anne & Sue

 

 

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