Precision fermentation unlocks safe, nutritious brewed chicken protein for pet food

Left is a tray of the modified yeast and at right is the dog food kibble that was used in the study. Credit: Fred Zwicky

Researchers have successfully developed a novel brewed chicken protein for pet food using precision fermentation, demonstrating that it is safe, nutritious and beneficial for canine gut health. This breakthrough comes from a collaboration between the University of Illinois Urbana-Champaign and Bond Pet Foods in Colorado.

The six-month feeding trial is the first to assess a precision-fermented protein combining chicken and yeast for pet nutrition. It marks a key advance in harnessing fermentation technology to produce sustainable, functional proteins for pets.

Creating the dog kibble

Published in Frontiers in Veterinary Science, the study genetically engineered Saccharomyces cerevisiae (brewer’s yeast) – already a common flavour enhancer and nutritional supplement in pet foods – to express proteins abundant in chicken muscle.

Bond Pet Foods’ scientists identified key chicken protein sequences and inserted the relevant DNA into the yeast genome. They then grew the yeast in industrial-scale stainless-steel fermentation tanks, harvested the biomass, and heat-treated and spray-dried it to create an inactivated whole-cell protein powder.

Researchers incorporated the protein powder into dry kibble and fed it to 32 healthy adult dogs. After two weeks on a control diet of chicken by-product meal and brewer’s rice, they divided the dogs into four groups, each receiving diets with zero, 15, 30 or 40 percent brewed chicken protein. They balanced all diets for nutrients and adjusted portions to maintain stable body weight.

Health effects

Professor Kelly Swanson, Director of Nutritional Sciences at Illinois and a corresponding author, said:

It was highly digestible and there were some beneficial changes to the dogs’ gut microbes and metabolites.”

The study found no allergic reactions, abnormal blood markers or adverse health effects. The dogs maintained healthy weights, normal food intake and consistent stool quality. Blood, urine and faecal analyses showed no significant differences between control and treatment groups.

Crucially, dogs consuming the brewed protein showed increased levels of short-chain fatty acids in their faeces, such as butyrate, propionate and valerate, that support colon health and reduce inflammation. While fat digestibility slightly declined at higher protein inclusion, overall fat absorption remained high.

Tomas Belloso, VP of Regulatory Affairs at Bond Pet Foods, said:

The main goal was to provide foundational protein for pet health, but it looks like there could be a secondary benefit from the soluble, fermentable fibres in the whole-cell product for the dogs’ large intestines as well.”

With the global pet food market valued at over £100 billion and growing demand for sustainable proteins, this research bolsters precision fermentation as a scalable production method. Long established in food and pharma for enzymes and vitamins, precision fermentation’s role in protein manufacturing presents exciting new opportunities for both human and animal nutrition.