This little guide will help you calculate and compare the GA content of dry food and wet food. I will try to make this as simple as possible. But of course with math, it can get confusing.
If you want to compare a can of wet food with a bag of dry food, then calculations are in order.
Here’s where I’ll try to help:
Dry cat food:
Crude protein …..min. 30.0%
Crude fat …………min. 23.0%
Crude fiber……….max. 1.0%
Wet cat food:
Crude protein ……min. 9.00%
Crude fat ………….min. 5.00%
Crude fiber ………..max. 2.00%
So just by looking, you would think that the dry food has more protein and fat because of the higher percentages. But that’s not the case. That’s why you calculate…
The first thing to do is to put both of these into a moisture free state. This is actually easy. A can or bag of food is 100%. I’m not sure how to explain this part but think of it as the total weight of all the ingredients put together. Everything in there equals 100%.
The dry cat food has 10% max moisture. So then what is the rest? The rest is dry matter. So you are taking that 100% and you minus the moisture content, because we want dry only.
100-10 = 90….the dry food is made up of 90% dry ingredients.
Do the same for wet food: 100-77 = 23…the wet food is made up of 23% dry ingredients (which makes sense because it’s WET food)
Here’s the not so easy to explain part:
The calculation is as follows: the guarantee analysis % listed (for dry food, protein, its 30%) is divided by the percentage of dry matter in the dry food (which we just calculated is 90%) then multiplied by 100.
So to calculate dry matter protein in the dry food: 30/90 x 100 = 33.3% protein
To calculate dry matter protein in the wet food: 9/23 x 100 = 39.1% protein.
The 9 came from the 9.0% crude protein min. in wet food analysis. The 23 is the 23% dry ingredients we just calculated. Multiply that by 100.
So the wet food actually has a higher percentage of protein in it.