Q. If you boil beans, they lose their protein?
According to google search, 1 cup RAW of pinto beans is 41 grams of protein, but if you boil them they become 1.9g / cup. Why is this so?
The discrepancy in protein per cup is due to the difference in volume between a dried bean and a cooked bean.
Dried beans can expand up to 2-3 times their original volume after an overnight soak and 3-4 times their original volume after cooking. So if you started with 1 cup of dried beans, you will on average end up with 3 cups of cooked beans. i.e. On average, 1 cup of dried beans will contain 3x the protein of 1 cup of cooked beans.
The same applies to other dried food stuff such as grains, legumes and lentils. The only difference is the amount of water they will absorb. To make it easier and less confusing to track these calories, weigh them raw and log them based on the raw nutritional information for that ingredient.
Recipe book and cooking advice for beans, legumes and lentils:
Cooking Dried Beans,Peas and Lentils:
Dried grains to cooked conversions: