What is crude ash in dog food?

Written by Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. - Our editorial process

Ash in dog food is not the kind of ash you’d find after a fire but rather relates to the number of minerals that are in the dog food. It’s described this way as when the food is incinerated at very high temperatures the only thing that’s left is the minerals. These are things like calcium, iron, magnesium, potassium, zinc and other minerals like these that dogs need in their diets to grow and be healthy.

Where does ash in dog food come from?

Dog food cannot be produced without ‘ash’ and when testing dog food scientists will use a bomb calorimeter to burn the food. This will then allow them to work out what the energy density or Kcal/100g the food is, as well as how much protein, fibre and fats are in the food. After this process, they’re left with the mineral content of the diet, or ash. And of course, this is only for testing purposes and the actual food you buy won’t be burnt or include ash in it.

Is low ash content good in dog food?

Usually, dry dog foods have between 5 and 8 per cent ash and wet foods have between 1 and 2 per cent. Percentages have even gone up to the 10 per cent levels in some dog foods. Higher quality meat will have lower levels of ash because it will contain less bone than other meats. These levels could also vary depending on the type of meat with chicken and fish having lower ash content naturally whereas red meats have a higher ash content.

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Lower ash content is typically better as it means the meat that’s used in the food is of higher quality and there are fewer filler ingredients. What is more important though, is knowing how much of each mineral is in your dog food and how these minerals can affect your dog.

Is ash in dog food safe?

Ash in dog food is safe and good for your dog as it means there are minerals in the dog food you’re feeding (not actual ash from a fire), that are good for your dog’s health and growth. But you should be wary of food with percentages above 8% as this generally means the meat is of lower quality and there are more filler ingredients in the food. Many large corporate dog food companies don’t disclose how much ash is in their recipes so it can be hard to understand whether the food you’re feeding is good quality or not.