Select your region:

Customer login

forgot your password?

Your region has been set to


Change region


IQI's response to the corona virus (Covid-19): More in our news update

Exploring the wonderful world of dietary fibers as a functional pet food ingredient

December 14 2021 - News

Increasing interest in dietary fibers

While interest in dietary fibers is increasing, many people still wonder why cats and dogs would actually require plant-based fibers? Cats and to a lesser extent dogs are true carnivores, after all. They have moderate colon fermentation capacity and require highly digestible food. But domesticated cats and dogs live under very different conditions than they would in nature and consume different nutrition. Dietary fibers can therefore be beneficial, but it is essential to take their specific functionality and unique benefits into account.

Fibers come in many shapes and sizes and are described in different ways for use in pet food formulations. This can make it challenging to understand the differences. But when we look at functionality, the main distinctions are between soluble and fermentable fibers versus insoluble and non-fermentable fibers. All of these should be part of a healthy diet for cats and dogs and can be found in a variety of ingredients. So what is the difference?

Soluble fibers as a prebiotic

As the name suggests, soluble and fermentable fibers dissolve in water and gastrointestinal fluids, and are fermented in the large intestine. There, they become a substrate for the beneficial microflora in the gut that ferment the fiber into volatile short-chain fatty acids. This process is described as a prebiotic effect – the basis for good gut health. Prebiotics offer an effective reinforcement against digestive disorders, such as diarrhoea and inflammatory bowel disease, and help the animal to digest food more efficiently and promote more solid stools.

Insoluble fibers for good gut health

Insoluble fibers do not dissolve in water or gastrointestinal fluids and pass through the intestinal digestive tract fully or mostly intact. In doing so, they stimulate bowel functioning and aid digestion, regularity, and the processing of waste. Insoluble fibers have excellent water-retention capacity, which helps to improve stool quality and prevent anal gland problems. Insoluble fibers have applications in weight management by adding bulk to pet food. Depending on the specific length of fiber, insoluble fibers can also be used to help keep teeth clean and for feline hairball control.

Sources of dietary fibers

Dietary fibers for use in pet food are available from many different plant-based sources, such as carrot, oats, peas, beans, apples, tomatoes, beet, and seaweed. Many of these ingredients contain both soluble and insoluble, fermentable and non-fermentable dietary fibers in different ratios. An example of a fairly well-balanced ingredient is functional carrot fiber, which is derived exclusively from the edible part of the carrot and contains around 27% soluble and 33% insoluble fibers. Functional carrot fiber also has very high water retention for a natural fiber of around 1 to 26. Another example is green seaweed, which contains 21% soluble and 17% insoluble fibers.

High concentration of soluble fibers

As I explained in one of my previous blogs, seaweeds are one of the most concentrated sources of soluble fibers, with levels as high as 40%. Another excellent source of soluble fibers is oat beta-glucan, a soluble oat bran fiber extracted from wholegrain oats without the use of chemicals. The dietary fibers can be used as a dietary supplement for dogs, acting as a prebiotic as well as offering other important health and functional benefits. Research has shown that oat beta-glucan helps to reduce blood cholesterol levels and maintain blood cholesterol concentrations that are within the normal range, thereby reducing the risk of dogs developing coronary heart disease. Likewise, research has indicated that oat beta-glucan as a dietary supplement helps to maintain healthy levels of blood glucose.

High concentration of insoluble fibers

By far the highest concentration of insoluble fibers can be found in purified cellulose powder, wood fibers from which the lignins and hemicellulose have been removed through a so-called sulfate process. Due to the chemical process used to produce purified cellulose powder, however, it is not always considered a fully natural product. A more novel, fully natural alternative to cellulose is Miscanthus, also known as Elephant Grass, which contains around 79% insoluble fibers, 1% soluble fibers, and also 13.5% Xylooligosaccharides (XOS) prebiotics.

Other fully natural alternatives are pea hull fiber (PHF), which contains 56% insoluble fibers, and rice bran, which contains 21% insoluble fibers. Rice bran, however, also contains a fat percentage of 18.3%, but provides different health benefits to dogs, such as helping to prevent heart disease.

White paper on natural dietary fibers

Are you interested in learning more about choosing the right fiber sources for pet diets? Our white paper explains all you need to know about the differences and sources of soluble and insoluble, as well as fermentable and non-fermentable, fibers for pet food applications.

About Geert van der Velden

Geert van der Velden is IQI Trusted Petfood Ingredients’ Innovation Manager responsible for Business Development, generating new products and concepts that meet the needs of existing and new customers. Geert has more than 25 years’ experience in the international pet food industry and has gained knowledge and experience in many sections of IQI’s business.

View all white papers Stay informed