With St. Paddy’s Day coming up, along with corned beef, potatoes, and cabbage, lots of Irish soda bread is going to find its way onto our tables. It’s one of the easiest quick breads to make, as well as one of the quickest to go stale, so I’m amused when I see “fresh” soda bread for sale in stores already. How fresh is it going to be in a week? What is put in it to make it last a week or more? Real soda bread has a shelf life of about a day. Make your own, and avoid all those unnecessary preservatives.
Soda bread is a basic quick bread which consists of flour (sometimes whole wheat, but more often all-purpose white flour), baking soda, salt, and sour milk or buttermilk. Sometimes butter is added, although it’s not necessary. Other additions include sugar, currants or raisins, but these are “dress-ups.” It is simplicity itself to make, but a few pointers are in order.
Stir all the dry ingredients together in a large bowl. (If your recipe calls for butter, now is the time to cut it in.) Make a well in the center of the dry ingredients, and pour in the buttermilk while stirring with a fork. Continue stirring until the dough comes together, then turn out onto the counter, which has been floured.
Working quickly, knead the dough just until it’s smooth. Don’t overdo this step, or your bread will be tough. Form it gently into a ball, and cut a deep cross in the top without cutting all the way to the edges of the dough. This cross allows the bread to expand without cracking.
You can bake soda bread on a baking sheet, but you’ll get a nicer crust if you bake it in a cast iron skillet or Dutch oven. If choosing the Dutch oven, use the cover for the first 30 minutes of baking; remove it for the last 10 minutes so the crust can brown. Remove the bread from the skillet or Dutch oven carefully, and allow it to cool on a rack. When serving, break the bread along the lines created by the cross.
What makes soda bread rise? It’s the interaction of the alkaline (the baking soda) and the acid (the buttermilk) ingredients. When combined, they give off carbon dioxide bubbles, which are what raise the dough. While it’s always important to measure accurately, it’s especially important with baking soda. Too little won’t leaven your dough; too much will cause too much bubbling. As those bubbles run into one another, they’ll burst and the dough won’t rise properly.
Baking powder, on the other hand, is an alkaline (baking soda) mixed with a dehydrated acid. Most baking powders these days are double-acting, meaning they contain two dehydrated acids, one of which is activated by liquid, the other by heat. So there’s an initial leavening action when the liquid ingredients are added to the batter or dough, and another when the item is baked. This ensures a good rise even if there’s a delay between mixing of the product and its baking. (You may have seen recipes for muffin batters which can be stored in the refrigerator for a week or more; double-acting baking powders make this possible.)
What about recipes which call for both baking soda and baking powder? Isn’t one sufficient? Not necessarily. Baking soda neutralizes acidity, so it may be included to modulate the flavor of an ingredient like yogurt, buttermilk, or molasses. It also tenderizes by weakening proteins in flour, and promotes browning. If you omit the baking soda in a recipe like this, it will rise properly, but may be pale or less tender.
Understanding the difference between baking soda and baking powder is important. Once you know how each works, it will be easy to tell what purpose each serves in a recipe and why it’s there. So here’s your test question of the day — why (besides the name) is Irish soda bread made with baking soda and not baking powder?