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Your recipe for Tamale Pie with Black Beans has me puzzled.
Why is there such a discrepancy in the calorie content of dried versus canned black beans? I would think it would be less. Please explain.
2 ounces dried black beans = 193 calories, <1g fat, 0g sat fat, 0g mono fat, 12g protein, 35g carbohydrates, 3mg sodium, 0mg cholesterol
Versus: 1 cup = 8 ounces canned black beans = 200 calories, <1g fat, 0g sat fat, 0g mono fat, 14g protein, 36g carbohydrates, 158mg sodium, 0mg cholesterol
Does this mean that the 2 ounces of Black Beans, once cooked, will equal 8 ounces of wet or canned beans at this calorie amount?
There are two reasons for the difference. The main difference in dried beans and canned beans is quite simply water. Soaking or cooking beans in water (or any liquid) will expand both their weight and volume. This is because the beans absorb water, expanding them as well as adding weight.
In the measures for dried black beans on the website there are two different measurements. In the case of the dried beans, the most common measure used by the USDA is weight ounces. Canned beans are, however, most often measured in cups (fluid ounces).
As a rule of thumb with dried vs. canned beans, the ratio is 1:3. That is 1 cup of dried beans equals 3 cups beans after cooking. While there is some slight variation between beans depending on how long they are soaked or cooked, this is generally pretty accurate.
Thanks for writing,
Timothy S. Harlan, MD, FACP