Some sources (e.g., [en.wikipedia.org]) state that "crude protein" content and quality of sprouting lentils, beans, etc. increases with germination i.e. sprouting. The only source seems to be Morgan 1992. Since I cannot find the study online, I cannot verify the study even applies to these types of edible sprouts.

Every nutritional database I consulted (e.g., www.nutritiondata.com]) shows the protein content of sprouts to be MUCH LOWER than raw lentils (3-5X lower) and slightly lower than even cooked lentils. Same goes for mung beans, etc. And this seems to affect other nutritional factors too, including calories and Vitamins. For instance, Vitamin C increases but other vitamins drop.

I've looked at the amino acid profile of sprouted lentils compared with raw lentils. The profile changes slightly, so that some amino acids become more while others become less as a percentage of the whole. But since, on the whole, there is much less protein in sprouts, compared with cooking, the difference, if any, would be negligible.

Does anyone know the source of the claim that sprouting increases amount of protein or any evidence to support this?

I came to this post because I was looking for the answer to the same exact question. I was also looking at nutritiondata - for people reading this, yes, the serving size is the same for sprouted lentils as the raw/cooked lentil (1 cup).

Is it possible that nutritiondata.com separates the sprouts from the bean (as in sprouts that have a green leaf), and then does its evaluation? I've seen most raw foodists eat the entire bean with the sprout that's just barely sticking out. Maybe the "higher protein content" is referring to that type of sprouting and nutritiondata is referring to green sprouts...even though it clearly says "lentils, sprouted, raw"?