Grain Distillers Dried Yeast
Our ingredient score: 1 / 5 · Hulls, bran or pulp · How We Score
This ingredient is the dried yeast and grain residue left over after ethanol (mostly fuel alcohol) is made from grain; it adds some protein to the food, but the main reason it is chosen is that it is very low-cost. The bigger problem is mold toxins: toxins in the grain such as aflatoxin are not destroyed during fermentation, become about three times more concentrated in the leftover residue because the starch has been removed, and can damage the cat's liver. In a 2010 survey by the US Food and Drug Administration (FDA), low levels of antibiotic residues were found in some samples. Its quality depends entirely on the plant it comes from, and the label gives no information about this. It should not be confused with brewer's yeast ("brewers dried yeast"); that is a much cleaner product.
Common Questions
Is grain distillers dried yeast the same as brewer's yeast?
No. It should not be confused with brewers dried yeast, which is a much cleaner product.
Is grain distillers dried yeast safe for cats?
Grain distillers dried yeast is the dried yeast and grain residue left after grain is fermented into ethanol. Ethanol plants use antibiotics to control bacteria, and in a 2010 FDA survey of distillers products, 4 of 46 samples contained low levels of antibiotic residues. FDA collected the data to support policy and did not anticipate regulatory follow-up. For a cat with a medical condition, ask your veterinarian.
Source: fda.gov
Why is grain distillers dried yeast in cat food?
It is a low-cost ingredient from the fuel ethanol industry. After grain is fermented, the yeast and leftover grain solids are dried and sold as feed. It adds some protein, but price is the main reason it is used. Quality varies with the ethanol plant it comes from, and the label does not say which plant supplied it.
Why are mold toxins more concentrated in distillers grains?
Fermentation turns the grain's starch into ethanol, which is removed, but mold toxins such as aflatoxin are not broken down. The same amount of toxin ends up in a much smaller mass of leftover material, roughly three times more concentrated than in the original grain. Quality control at the source plant matters for that reason.
Does grain distillers dried yeast contain alcohol?
No meaningful amount. The alcohol is distilled off during ethanol production before the yeast and grain residue are dried, and drying drives off what little remains. What reaches the cat food is a dry powder made of spent yeast and grain solids, used for some protein at low cost.
How does Pettings score grain distillers dried yeast?
Pettings gives grain distillers dried yeast 1 out of 5 and lists it under hulls, bran or pulp. It appears on 6 of the 149 dry cat foods we list. It is chosen mainly for low cost, and mold toxins in the grain end up concentrated in it. Each food's page shows how it scores overall.
How Foods With Grain Distillers Dried Yeast Compare
Grain Distillers Dried Yeast is on the label of 6 of the 149 dry cat foods we list.