Without a measuring method known as the "dry matter basis", it would be very difficult to compare cat food products.
Pet food companies report on the nutrient content of each product using what's known as the "Guaranteed Analysis." This Guaranteed Analysis is the equivalent of the Nutrition Facts panel that is printed on all human food products sold in the USA and Canada.
In pet food products, the Guaranteed Analysis is designed to allow consumers to compare the amounts of four (or more) critical nutrients:
However in practice, using these numbers as published in the Guaranteed Analysis can actually be quite misleading - especially when comparing wet and dry products.
According to the FDA:
“To make meaningful comparisons of nutrient levels between a canned and dry product, they should be expressed on the same moisture basis.”
The measuring method known as the "Dry Matter Basis" (or DMB) allows us to do that. To summarize, the DMB is a calculation method that removes the moisture content from a product and then reports the remaining nutrient values (protein, fat & fiber) based on the percentage of the remainder.
Removing the moisture content before evaluating products is especially important when comparing a wet food vs a dry one. Wet cat food typically consists of 80% moisture, while dry foods are approximately 10% moisture.
This can be most easily illustrated using 2 Wellness products: Signature Selects Shredded Boneless Chicken With Chicken Liver and Wellness Indoor Health Deboned Chicken & Chicken Meal.
|Nutrient||Signature Selects Chicken||Indoor Chicken|
Looking at the above chart, it appears the dry Indoor Chicken has over 3 times the protein the wet Signature Selects! However, once the moisture is removed from the equation and the other nutrients are recalculated as a percentage of the remainder, we can see that this is not the case.
|Nutrient %||Signature Selects Chicken||Indoor Chicken||Calculation Formula|
|% Dry Matter Protein||53.3%||33.7%||
|% Dry Matter Fat||13.3%||13.5%||
|% Dry Matter Fiber||10.0%||5.6%||
|% Dry Matter Ash||20.0%||7.3%||
Using the above DMB chart above instead, we can see the wet Signature Selects Chicken product actually contains 53% protein (for all non-moisture weight), compared to the 33% that is in the dry Indoor Chicken product. Instead of only consisting of 1/3 of the protein of the dry food as the Guaranteed Analysis initially suggests, the wet food actually consists of 50% more! Without calculating the DMB values for the two products, it would be impossible to see this.
Fortunately, CatFoodDB has calculated the Dry Matter Basis values for each of our products reviewed, allowing you to easily compare and contrast without having to manipulate the numbers yourself!