At first glance it seems like kibble contains more protein. This is because kibble has such low moisture content it appears there’s a larger percentage of protein. This is never the case. In order to get the true amount, a comparison should be made on a dry matter basis. Even the FDA warns, “To make meaningful comparisons of nutrient levels between a canned and dry product, they should be expressed on the same moisture basis.” In other words, the nutrient levels can only be accurately assessed when all of the water been removed from both products. Since water has no protein, fat or fiber you have to analyze the food with out water in the mix.
For example, if comparing a raw label listing 10% protein with a kibble label stating 23% protein, at first it appears the kibble has more protein, but when compared without the moisture, the raw food clearly contains significantly more protein.
To determine the amount of protein on a dry matter basis, simply divide the reported amount of protein (in this case, 10%) by the total amount of dry matter (25%) in the raw food. This works for any other nutrient to.
Then, multiply the result by 100. Dry Matter Protein Content = (10/25) x 100 = 40%