If you say edible insects, you say proteins

August 07, 2017

If you say edible insects, you say proteins

If you say insects, you say proteins.
When you are searching the protein content of insects, you can be a bit confused by finding numbers very different from each other.

The first reason is that, as we know, all the insect species have different nutritional values.

The second reason is that the protein content can be expressed on the live weight, meaning on the insect as it is, or on the dry weight, namely on the dry insect. Since the body of the insects, like our own, is composed by water for its biggest part, the percentage of protein is bigger if expressed on dry matter.

According to a review of nutrient composition of twelve commercially available edible insects, their protein content ranged from 15 to 35 % on live weight, but on dry matter basis the protein content is between 52 to 76 %.
This is not a way to cheat showing a higher protein content: as we don’t consume fresh insects, almost all the insects that we can include in our diet are dry, so the protein content on dry matter basis gives us a good estimate of the protein that we can obtain from insects.
It’s an estimation because we are referring to crude protein, which is the most used way to calculate the protein content of food: the structure of the proteins is made, among the rest, by nitrogen; so the nitrogen content is determined and then multiplied by a correction factor (i.e. the average percentage of nitrogen in that proteins) to obtain the approximate amount of protein in the food.

As insects contain chitin, and therefore some non-protein nitrogen, this may result in an overestimation of the protein content.
But don’t worry: we are still speaking about a considerable pack of true protein!

A study on mealworms showed how the crude protein (51.5%) was higher than the true protein content (43%), which is still bigger than the protein content of meat (26%).