Pet Food Labels - decoding the label, myths and facts !
1. What is the difference between "chicken" and "chicken byproducts" and "chicken byproduct meal"?
"Chicken" refers to any combination of chicken flesh, skin, and bone. "Chicken byproducts" refers to the head, neck, and viscera (internal organs which can supply excellent nutrients). Viscera include lungs, spleen, kidney, brain, liver, blood, bone, fatty tissue, stomach and intestines freed of their contents and it does NOT include hair, horns, teeth, and hooves. "Chicken by product meal" refers to the head, neck, and viscera in which the byproducts have been ground up and the moisture has been removed.
The bad reputation of byproducts is not always deserved as the quality of the byproducts is determined by the proportion of the less digestible ingredients (such as feet and heads in poultry by products if they were included). You do not know the quality of the ingredients from the label - you must request additional information concerning these from the product manufacturer or find out by other ways. There are many grades of meat meal form low to high quality. The manufacturer picks a grade to use in their food. This is not listed on the pet food label. Cheaper grades of meat meal have higher ash contents and more expensive grade of meat meal have lower ash contents and higher digestibility. Low ash means reduced levels of ground up bone tissue in the meat meal.
So how can you, the consumer, determine the quality of the meat meal being used by the manufacturer? You can do this by determining the calcium content of the food. Calcium in pet food comes almost entirely from the meat meals. According to the USDA, plain striate muscle chicken meat, lamb meat, beef meat etc. contain only 0.01% calcium. So if the pet food says it has human grade chicken, why does the label say it has 1.3% calcium on a dry matter basis (13 times as much calcium as pure meat)? The calcium is higher because of the ground up bones in the meat meals! So a food with lower calcium content (i.e. 0.6 to 0.8% range) would have much less ground up bone (i.e. higher quality meat meal, low as meat meal) than the one with 1.3% calcium.
2. Ingredients on the label are listed in PREPROCESSED volume.
Because the ingredients are listed in preprocessed volume, a dry food component can start out as mostly water with some skin and bone and still be listed as "chicken". During the processing of the food, the water will be removed and the volume shrinks markedly (and you have no idea!).
Some of the dry foods have the first ingredient listed as chicken but in the processing of the food the chicken (high moisture content) is dehydrated and reduced to chicken meal during the mixing and extrusion process. If these ingredients were properly listed as chicken meal, they would be dropped lower on the ingredient list because they no longer have their water weight. So the dry food listing its ingredients as chicken, corn flour, chicken fat, soy protein ... most likely does not have more chicken than corn flour by weight in the finished kibble but this is legally allowed to be listed in this manner.
3. What does the name of a food tell us?
AAFCO states "beef" food must have at least 95% beef on a dry matter basis. "Beef entree/feast/dinner/etc" needs to only have 25% beef in it.
If the word "with" is in the name (i.e. cat food with beef) then the food only needs to contain 3% of the ingredients from beef.
READ the label if you have a food allergic pet as many foods have multiple protein sources that are not listed in the name of the food!
4. How do we really know what is in a dog food when the labels say "minimum" and "maximum"?
You must compare foods on the same basis and that is on a "dry matter" basis. This means the amount of a particular ingredient (i.e. protein) is expressed as a percent of the total solids in the can or bag (the moisture has been removed). If using the dry matter basis, you can compare a dry food to a canned food in a fair manner.
Here is how it can be done:
Dry food has about 10% moisture and the rest of the ingredients are 90% of the food. Let's say protein on the label is 25% and you want to convert that to a dry matter basis. Divide 25 percent by 0.90 percent = 27.8 %. This dog food which has 10% moisture and 25% protein on the label has 27.8% protein on a dry matter basis. You can perform similar calculations for the rest of the ingredients on the label (fat, fiber, etc.).
Canned and pouched food has about 75% moisture and the rest of the ingredients are 25% of the food. Let's say protein on the label is 10% and you want to convert it to a dry matter basis. Do the math again - divide 10 percent by 0.25 percent = 40%.
Isn't that interesting....if you compared the two foods in the grocery store aisle, you would be thinking the dry food had more protein than the canned food (25% vs. 10%). Now that you got your calculator out and compared the food on the same basis you notice the canned food had more protein (40% vs. 27.8%). Wouldn't it be nice if the pet food companies would put the ingredients on the label in a dry matter basis and make it easier for us!
5. Why aren't carbohydrates listed on the label - my cat is a diabetic and I need to know which foods are low carbohydrate!
Only basic nutrient percentages are required for the labels (carbohydrates not included). To figure out the carbohydrates in the food, add the listings of the protein, fat, fiber, moisture, and ash and then subtract from 100 percent to get the remainder which is the carbohydrates.
Crude protein min 9.5%
Crude Fat min 5.0%
Crude Fiber max 0.8%
Moisture max 75%
Ash max 2%
9.5% + 5.0% + 0.8% + 75% + 2% = 92.3%, 100% - 92.3% = 7.7% carbohydrate
but wait - remember to compare foods on a DRY MATTER basis......so 7.7/0.25 (remember the canned food is 75% moisture and the rest of the ingredients are 25%) = 31% carbohydrates on a dry matter basis (way too much for a diabetic cat!!).
6. What about protein sources?
Multiple protein sources supply a broader range of amino acids. There are animal based protein sources and plant based protein sources.
Animal based protein sources are obvious such as chicken, beef, fish, and lamb.
Plant based protein sources include wheat, corn germ, corn gluten meal, soy mill, soy meal, whey, and brewer?s yeast.
Corn gluten meal is the protein fraction of corn remaining after the starch, bran, germ, and oil are removed from the whole corn. It is an excellent source of high quality vegetable protein (60 to 65% protein) and is complementary with animal proteins. It is very palatable (cats love it), highly digestible, and low in phosphorus (spare those kidneys!).
Soybean meal is obtained by grinding the flakes that remain after removing the oil and hulls from whole soybeans. It is an excellent source of vegetable protein (45 to 50%), a good source of amino acids (tryptophan and lysine), a good source of potassium, highly digestible, and low in phosphorus (spare those kidneys again!).