Pita, Naan, and Matzo are all fantastic, but the sandwich game changed when the Egyptians discovered and recorded leavening agents to make bread in 1000 B.C. Since then, sourdough has played an essential role in feeding humanity for thousands of years. Sourdough fermentations can influence the vitamins and antioxidant content of baked goods, alter the glycemic index, influence the mineral absorption, and change baked goods’ gluten content. However, the interest in speeding up large-scale bread production has changed the bread manufacturing processes, which have changed the end products’ nutritional benefits. In this blog, we will review five of sourdough’s most relevant health and nutritional properties.
Sourdough and glucose levels
The Glycemic Index (GI) measures how foods affect blood glucose levels. Carbohydrates with a low GI value (55 or less) are digested at a slower rate, absorbed and metabolized, and cause a lower and slower rise in blood glucose. Therefore insulin levels are also slower to rise. The sourdough fermentation lowers the GI of bread, reducing starch digestibility. For example, a white wheat flour bread has a GI around 71; a white wheat flour sourdough bread has a GI around 54.
Sourdough and mineral absorption
Phytates are a naturally occurring compound found in all plant foods that can reduce the absorption of minerals. Sourdough fermentation reduces to less than half the phytate content of whole wheat bread, increasing mineral absorption (calcium, phosphorous, potassium, iron, zinc, magnesium).
Sourdough and blood pressure
Sourdough bread tastes saltier when compared to conventional bread. Therefore, sourdough bread allows lower salt content without affecting taste and other quality parameters (i.e., softness), potentially beneficial for people following a low sodium diet.
The manufacture of sourdough breads from different flours can synthesize compounds (GABA and ACE inhibitory peptides) with bioactive functions, including hypotension induction.
Sourdough and gluten sensitivity
During the fermentation of sourdough, lactic acid bacteria breakdown the flour proteins, which can lower gluten levels (<50% of traditional products) and positively influence the allergy and intolerance responses of cereal sensitive individuals.
Sourdough and IBS
FODMAPs are types of carbohydrates found in certain foods. Both gluten and FODMAP carbs are common triggers of IBS symptoms; thus, most IBS may find relief when following a gluten-free and a FODMAP free diet. Sourdough fermentation can reduce the gluten and FODMAP content of breads, which results in reduced IBS symptoms.
How to prepare sourdough bread
To make a sourdough bread, you need a starter. There are several starter recipes, some of them include only flour and water, and others may call for flour, water, dry yeast, and sugar. The basic started is a mixture of flour, water, and microorganisms that flavors and leavens bread. Wild yeasts and bacteria are naturally present on wheat kernels and flour ground from them. Still, it takes time and proper care for them to multiply and transform the initial mixture into a bubbly, boozy-scented culture that can leaven bread. Be careful if your starter turns pink or orange, or it just smells “off,” toss it.
The recipe of the week comes via Cook’s Illustrated
Sourdough Discard Drop Biscuits
(Makes 12 biscuits)
1¼ cups (177 grams) all-purpose flour
2 teaspoons baking powder
½ teaspoon baking soda
1 teaspoon sugar
¾ teaspoon table salt
½ cup milk
¾ cup plus 2 tablespoons (226 grams) 100% hydration sourdough discard (cold)
8 tablespoons unsalted butter, melted and cooled slightly (about 5 minutes), plus 2 tablespoons melted butter for brushing biscuits
- Adjust oven rack to middle position and heat oven to 475 degrees. Whisk flour, baking powder, baking soda, sugar, and salt in a large bowl. Whisk milk and sourdough discard in medium bowl. Add 8 tablespoons melted butter and stir until butter forms small clumps.
- Add discard mixture to dry ingredients and stir with a rubber spatula until just incorporated and batter pulls away from the sides of the bowl. Using greased 1/4-cup dry measure, scoop level amount of batter and drop onto parchment-lined rimmed baking sheet (biscuits should measure about 2 1/4 inches in diameter and 1 1/4 inches high). Repeat with remaining batter, spacing biscuits about 1 1/2 inches apart. Bake until tops are golden brown and crisp, 12 to 14 minutes.
- Brush biscuit tops with remaining 2 tablespoons melted butter. Transfer to wire rack and let cool 5 minutes before serving.
To refresh day-old biscuits, heat them in a 300-degree oven for 10 minutes.
Note: A ¼-cup (#16) portion scoop can be used to portion the batter.