'Kibble Matter' Explained
Kibble matter isn't a 'real' term; I made up and am using on this site to describe a guaranteed analysis that has been converted to a 10% moisture base (the most common moisture level for dry kibble). This is similar to a conversion to dry matter, and the name is kind of a pun on it.
Full explanation: Why conversion is necessary
Dry kibble is well... dry. It typically only contains 10% moisture. Commercial raw, canned food, plain meat, basically anything moist is well... moist. (Easy enough?)
Unfortunately, this makes comparing kibble and moist foods pretty difficult. Why? Because the guaranteed analysis is listed 'as fed'.
Here's 2 cat food products by the same company (Wellness). One is their standard dry adult cat recipe (chicken based) and the other is their standard chicken canned food:
At first glance, the dry food would appear to have more protein. 36% vs 10% seems like a no-brainer. But the canned food is 78% water- what would happen if we took that out?
"Dry Matter" is a term that refers to nutrient values that are calculated as if all the water was removed from the food. For example:
For the wellness dry food: Dry matter protein = [36 /(100 - 11)] * 100% = 40.4%
Here's what that looks like in graph form:
Suddenly we see that the canned food actually has a little more protein and fat!
Saying that a moist food has less protein than a dry one (without doing any calculations) is like saying that a hot dog has more protein than a hot dog with a glass of water. It may be true on a 'pound for pound' measurement, but the answer that we're looking for is the one that is smart enough to exclude water. I don't care how much water is in my ferret's food; I care about whether the rest of the stuff in it is meat or not.
Kibble matter is...
Kibble matter is my own term. It's basically my way of converting moist foods into dry kibble (number wise) to save the trouble of having to convert EVERYTHING to dry matter. I do this both to save time and trouble on calculations, and because most people are used to and understand values for 'as fed kibble' better than dry matter. For example, I know that I like dry ferret food to be 40% or more protein, and that Innova EVO is about 50% protein, but I wouldn't know off the top of my head what those numbers are when converted to dry matter. I'm used to reading kibble bags. To calculate kibble matter, I take the dry matter values and add 10% water back in.
Here's what the two examples from Wellness look like on the graphs:
Note that the dry food looks the same as it did originally, since we're using a very similar moisture to its original value. It's just the moist food that we've converted so that it can easily be compared to the kibble.