Brewer’s Yeast and Palatability in Dry Pet Food: What the Trials Show

Dried brewer’s yeast can lift the palatability of dry pet food, and the effect is clearer in cats than in dogs. In a controlled trial published in Translational Animal Science in 2023, cats ate about twice as much of an extruded diet containing 10% dried yeast as of the same diet without it, while dogs showed a smaller preference that was not statistically significant. Digestibility and stool quality were unchanged in both species. This guide explains why yeast tastes good to dogs and cats, how whole dried yeast differs from processed yeast palatants, and how to test it in your own formula.

What the controlled trial found

Davenport and colleagues (2023) fed beagle dogs and cats two dry extruded diets formulated to AAFCO adult maintenance profiles. The test diet included 10% dried Saccharomyces cerevisiae yeast in place of part of the pork meal and wheat middlings; the control diet had none. Palatability was measured with a two-day, two-bowl test in 20 dogs and 20 cats, with bowl positions swapped on day two.

Source: Davenport, Block and Adolphe (2023), Translational Animal Science 7(1): txad107.

Two points matter for formulators. First, the cat response grew on the second day, which suggests a learned preference rather than only a first-bite effect. Second, the dog result was mixed: dogs reached for the yeast diet first more often, but did not eat significantly more of it over two days.

Why yeast tastes good to dogs and cats

Yeast is rich in glutamic acid and nucleotides, the compounds behind the savoury taste known as umami. Industry work on yeast palatants attributes their effect to this umami profile, and researchers studying cat food have linked the response to the T1R1/T1R3 taste receptor, which detects amino acids and is enhanced by nucleotides. Brewer’s yeast also brings digestible protein and naturally occurring B-vitamins, so it adds nutrition alongside flavour.

Whole dried yeast vs processed yeast palatants

Not all yeast ingredients work the same way. Processed forms such as yeast extract, autolysed yeast and hydrolysed yeast have more soluble, free amino acids and nucleotides, which makes them stronger as a surface coating. In an industry trial with a 0.5% coating on extruded dog food, all three processed prototypes were preferred over inactive dry yeast; in cats the differences were weaker. Whole dried brewer’s yeast therefore works best as a recipe ingredient, mixed in before extrusion, rather than as a top coating.

• In the recipe: dried brewer’s yeast is commonly used at 1–3% of dry and wet pet foods; the 2023 trial used 10% without harming digestibility or stool quality.
• As a coating: yeast extract is applied at fractions of a percent. In a two-bowl test with 20 cats, a 0.5% coating of yeast extract blended with sodium pyrophosphate was preferred over the control and over yeast extract alone.

Dose matters in cats. The same study cites earlier work in which 1.5% yeast extract in a cat diet reduced palatability, so cat formulas should be tested rather than assumed.

How to test it in your own formula

1. Run a two-bowl test over at least two days, with the bowl positions swapped on day two to rule out side bias.
2. Record both first choice and intake ratio. A ratio of 0.67 or above, roughly 2 : 1, is usually read as a strong preference.
3. Test the final kibble, not the ingredient alone, with the palatant coating your product will carry.
4. Ask whether the yeast is debittered. Residual hop bitterness can work against acceptance, so confirm the processing with your supplier.
5. Keep the yeast dry and sealed. Moisture pick-up during storage can bring off-notes that panels notice before analysis does.

How TBESBY supports palatability trials

TBESBY dried brewer’s yeast is drum-dried at our own facilities in Vietnam, with crude protein of 40–46%, moisture below 10% and a 12-month shelf life. We send 1–2 kg free of charge for laboratory and palatability trials; you cover the courier cost, which we credit against your first contract.

Related reading: Brewer’s yeast for dogs · Brewer’s yeast for cats · Debittered brewer’s yeast · Safety specs for brewer’s yeast in pet food · Upcycled pet food ingredients · Brewer’s yeast claims in pet food marketing

Sources

• Davenport GM, Block SS, Adolphe JL (2023). Effects of extruded pet foods containing dried yeast (Saccharomyces cerevisiae) on palatability, nutrient digestibility, and fecal quality in dogs and cats. Translational Animal Science 7(1): txad107
• Oliveira RT de, Haese D, Kill JL, et al. (2016). Palatability of cat food with sodium pyrophosphate and yeast extract. Ciência Rural 46(12): 2202–2205
• Petfood Industry. Improving pet food palatability: yeast extract, hydrolyzed yeast