Ingredient file // Plant protein
Potato Protein
A useful plant protein with a label catch
Potato protein is recovered from the liquid left during potato starch production and dried into a concentrate. It supplies amino acids, but it also raises a food's protein figure without adding meat. Its presence alone says little about the balance of the finished food.
- What it is
- A dried protein concentrate recovered from potato juice during starch production.
- Made from
- Potato juice after starch separation
- Main job
- Concentrated plant protein
- Typical amount
- Not published; tested diets used 3.7 to 11.2%
- Watch for
- Supplier variation in potato glycoalkaloids
- Not the same as
- Potato starch
Our read // In our catalog
In 1 of every 21 foods we track
Share of foods that list it
5%
117 of the 2,508 foods with an ingredient list on file, from 21 brands. 85 dry dog food, 30 wet dog food, 2 dog food topper.
Each square is 1% of the catalog
Where it sits on the label
Median position 8. In the top five of 37 foods, so it is usually a supporting ingredient.
Above the salt
Almost always listed before the salt, so there is more of it than a pinch.
Price per lb
Median of the cheapest bag price across 65 priced foods, 7% above the catalog. The price is the food's, not the ingredient's.
Who leans on it
27%
of the foods that list it are from Merrick. 21 brands use it in total.
What it is
How it is made
Starch plants separate potatoes into starch, pulp and a liquid that still contains protein. Recovering and drying that protein creates another saleable ingredient from the same crop.4,5
- 01 // Source Potatoes Potatoes enter a starch plant, which separates the starch from the liquid carrying potato protein.
- 02 // Process Protein recovered The protein is concentrated from potato juice by a method such as coagulation or filtration.
- 03 // Process Concentrate dried The recovered protein is spray dried into a powder for storage and transport.
- 04 // Output Potato protein The dry concentrate reaches the kibble plant as an ingredient that contributes mostly protein.
What is in it
Composition, dry matter
80
% protein
About four-fifths of the dry concentrate was crude protein in a starch-plant survey. Its main contribution to kibble is protein, not starch.
Why it is in the bag
What the manufacturer gets
-
01
Raises recipe protein
A concentrate with about 80% crude protein makes a substantial contribution to the finished food's protein figure without increasing its meat content.4,5
-
02
Supplies amino acids
Potato protein's essential amino acids tested as readily digestible in a rooster assay. Formulators still have to balance the amino acids across the complete recipe.4
-
03
Sells a starch byproduct
Starch production leaves potato juice containing protein. Recovering it gives the processor another ingredient to sell from potatoes already being processed.4,5
-
04
Offers another protein source
A dog diet for chronic intestinal disease paired potato protein with fish meal and other ingredients. That shows a formulation use, not a proven benefit of potato protein alone.3
How much A study of 8 dogs fed mixed plant-based diets containing 3.7 to 11.2% potato protein; a typical commercial amount is unpublished.1
Our read // The claims
What the evidence supports
Strong: controlled studies in dogs agree. Some: small or mixed dog data. Thin: mechanism or lab work only. None: nothing, or the evidence points the other way.
-
Critics say
Potato protein raises protein without adding meat
Evidence
- Strong
- Some
- Thin
- None
Crude protein includes plant protein. Potato protein measured about 80% protein on a dry basis in a starch-plant survey, so adding it raises a food's protein figure without raising its meat content.4,5
-
Brands say
Dogs digest potato protein exceptionally well
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
Its essential amino acids tested as highly digestible in an assay using 4 roosters per treatment. An 8-dog study fed mixed diets containing potato protein, so neither study proves exceptional digestibility of this ingredient in finished dog food.1,4
-
Brands say
Potato protein soothes sensitive guts
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
A study reported improvement in 14 dogs with food-responsive diarrhea and 7 with inflammatory bowel disease. The diet also contained fish meal and added omega-3 fats, and some dogs received drugs. It did not isolate potato protein.3
-
Owners say
Potato protein causes heart disease in dogs
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
FDA reports included foods with potato ingredients but cannot identify a cause. In a 60-dog, 18-month trial, a diet containing potato protein did not produce clinical DCM. That trial compared whole recipes, not potato protein alone.2,7
-
Critics say
Potato protein is just filler
Outruns the evidence
Evidence
- Strong
- Some
- Thin
- None
A starch-plant survey measured about 80% crude protein in the concentrate, and a rooster assay measured digestible amino acids. It has a nutritional job. The fair label concern is how much of the food's protein comes from plants.4,5
Straight answers
What owners ask
-
Q01
Is it just filler?
NoIt contributes protein and amino acids. The label does not show how much of the finished food's protein comes from potato protein, so read it alongside the named animal proteins and the rest of the recipe.4,8
-
Q02
Is it the same as potatoes?
NoPotato protein is recovered while starch is being separated. In the starch-plant survey, the concentrate was about 80% protein and under 8% starch on a dry basis. It serves a different purpose from potatoes or potato starch.5
-
Q03
Does it replace meat protein?
In partIt contributes amino acids that a formulator might otherwise supply through another ingredient. A rooster assay identified tryptophan as its limiting amino acid against adult dog targets, so the complete recipe's balance matters.4
-
Q04
Should the heart reports worry me?
Read the recipeFDA reports cannot identify potato protein as a cause. A trial of 60 dogs also found no clinical DCM on its potato-protein diet, though it tested a complete recipe. Look at how heavily the food relies on potato and pulse ingredients.2,7
Who uses it
Brands, best sellers and the company it keeps
Top brands, by foods that list it
Plus 11 more brands.
Amazon best sellers that list it
Rank on Amazon's dog food best seller list, checked October 2026.
Usually listed with, share of the foods that list it
- Natural Flavor 60%
- Potatoes 46%
- Sweet Potatoes 38%
- Flaxseed 34%
- Chicken Fat 27%
- Peas 26%
- Chicken 25%
- Chicken Meal 23%
- Pea Protein 20%
- Canola Oil 18%
- Salmon 18%
- Brown Rice 18%
On the shelf
Foods that list it
117 foods in our reviews list it. Here are some of them.
Show 54 more
Simply Nourish Source High Protein Grain Free Adult Dry Dog Food38.9% proteinHalo Holistic Vegan Plant-Based with Kelp Recipe Adult Dry Dog Food29.7% proteinMerrick Backcountry Bone Broth Coated Beef & Bison Dry Dog Food38.2% proteinPure Balance Pro+ Chicken Recipe for Healthy Weight Can Wet Dog Food34.1% proteinRayne Nutrition Plant-Based Chunky Stew Wet Dog Food27.1% proteinNatural Balance Limited Ingredient Bison & Sweet Potato Recipe Paté Wet Dog Food27.3% proteinNatural Balance Limited Ingredient Diets Sweet Potato & Salmon Recipe Wet Dog Food22.7% proteinHill’s Science Diet Adult Perfect Digestion Small & Mini Chicken & Vegetables Entrée Wet Dog Food22.7% proteinBlue Wilderness Denali Dinner Wild Salmon Venison Halibut Dinner Wet Dog Food45.5% proteinBlue True Solutions Skin & Coat Care Whitefish Recipe Dog Food Topper31.8% proteinPurina Pro Plan Sensitive Skin & Stomach Beef & Oat Meal Entrée Classic Wet Dog Food29.5% proteinPurina Pro Plan Puppy Sensitive Skin & Stomach Salmon & Rice Entrée Classic Wet Dog Food29.5% proteinRayne Nutrition Rabbit Maint Rabbit-Maint Dry Dog Food28.4% proteinRayne Nutrition Low Fat Kangaroo Maint Quinoa Low Fat Kangaroo-Maint with Quinoa Dry Dog Food33.0% proteinRayne Nutrition Low Fat Kangaroo-MAINT with Ancient Grains Dry Dog Food33.0% proteinAvoDerm Grain Free 12 Cans- Chicken & Veggies Recipe In Gravy Wet Dog Food43.8% proteinAvoDerm Grain Free 12 Cans-Whitefish, Salmon & Veggies Recipe In Gravy Wet Dog Food43.8% proteinAvoDerm Grain Free 12 Cans- Stew Beef & Veggies Recipe In Gravy Wet Dog Food43.8% proteinBil-Jac Sensitive Solutions Skin & Stomach Support Chicken & Sweet Potato Recipe in Gravy - Bil-Jac Wet Dog Food38.9% proteinBil-Jac Sensitive Solutions Digestive & Immune Support Turkey & Pumpkin Recipe in Gravy - Bil-Jac Wet Dog Food38.9% proteinHalo Holistic Vegan Plant-Based Recipe Adult Wet Dog Food26.1% proteinWellness Core Digestive Health Chicken - Dog Wet Dog Food54.5% proteinWellness Complete Health Lamb & Sweet Potato Wet Dog Food36.4% proteinWellness Core Digestive Health Beef Wet Dog Food54.5% proteinWellness Core Digestive Health Lamb Wet Dog Food54.5% proteinRoyal Canin Veterinary Canine Selected Protein PR loaf Wet Dog Food23.8% proteinBlue Wilderness Turkey & Chicken with Grains Wet Dog Food45.5% proteinMerrick Grain Free Thanksgiving Day Chicken & Turkey Wet Dog Food44.4% proteinMerrick Grain Free Puppy Plate Real Chicken Wet Dog Food50.0% proteinMerrick Grammy’s Grain Free Chicken Pot Pie Wet Dog Food44.4% proteinMerrick Classic Healthy Grains Kitchen Comforts Beef Tips & Rice Stew Wet Dog Food44.4% proteinMerrick Grain Free Turducken in Gravy Wet Dog Food44.4% proteinMerrick Grain Free Puppy Plate Real Beef Wet Dog Food44.4% proteinNutro Limited Ingredient Diet Lamb & Potato Recipe Wet Dog Food31.8% proteinMerrick Cowboy Cookout Grain Free in Gravy Wet Dog Food44.4% proteinNutro Natural Choice Dry Dog Puppy Lamb and Brown Rice Dry Dog Food31.1% proteinPure Balance Grain-Free & Poultry-Free Lamb & Fava Bean Recipe Dry Dog Food30.0% proteinAbound Wild Beginnings Adult Beef, Venison & Lamb Dry Dog Food33.3% proteinAbound Wild Beginnings All Life Stages Chicken, Turkey & Duck Dry Dog Food37.8% proteinAbound Wild Beginnings All Life Stages Salmon, Whitefish & Trout Dry Dog Food37.8% proteinRayne Nutrition Adult Health RSS Adult Health-RSS Dry Dog Food25.0% proteinNatural Balance Limited Ingredient Reserve Grain Free Duck & Potato Recipe Dry Dog Food26.7% proteinIams Proactive Health Sensitive Skin & Stomach Adult Salmon Dry Dog Food26.7% proteinHill’s Prescription Diet d/d Skin/Food Sensitivities Potato & Salmon Formula Dry Dog Food20.6% proteinHill’s Prescription Diet d/d Skin/Food Sensitivities Potato & Venison Formula Dry Dog Food15.6% proteinHalo Senior Grain-Free Holistic Turkey, Turkey Liver & Duck Recipe Dry Dog Food26.7% proteinBlue Wilderness Rocky Mountain Recipe Large Breed Adult Red Meat Dry Dog Food31.1% proteinBlue Wilderness Rocky Mountain Recipe Large Breed Adult Bison Dry Dog Food31.1% proteinRoyal Canin Veterinary Selected Protein PW Dry Dog Food24.4% proteinRoyal Canin Veterinary Selected Protein PR Dry Dog Food21.1% proteinRoyal Canin Veterinary Selected Protein PD Dry Dog Food21.1% proteinRoyal Canin Veterinary Vegetarian Dry Dog Food18.9% proteinRoyal Canin Veterinary Selected Protein PW Moderate Calorie Dry Dog Food25.0% proteinRoyal Canin Veterinary Selected Protein Adult PV Dry Dog Food21.1% proteinOur read // On the bag
Count it as protein from potatoes
When potato protein sits high on an ingredient list, expect it to contribute meaningfully to the protein figure. Check which named animal proteins sit around it and whether potatoes, potato starch or pulse proteins appear separately. Judge the complete food and its nutritional adequacy, not the protein percentage alone.
Sources
What we read
Checked September 1, 2026.
- 1 Investigation of the Digestibility, Fecal Characteristics, and Palatability of Oil Mil By-Products as a Plant-Based Protein Source in Canine Diets
- 2 Different carbohydrate sources in dog foods supported overall health and cardiac function: an 18-mo prospective study in healthy adult dogs
- 3 Fish-meal diet enriched with omega-3 PUFA and treatment of canine chronic enteropathies
- 4 Use of precision-fed cecectomized rooster assay and digestible indispensable amino acid scores to characterize plant- and yeast-concentrated proteins for inclusion in canine and feline diets
- 5 Variability in the composition of potato protein concentrate produced in different starch factories - A preliminary survey
- 6 Risk assessment of glycoalkaloids in feed and food, in particular in potatoes and potato-derived products
- 7 FDA Investigation into Potential Link between Certain Diets and Canine Dilated Cardiomyopathy
- 8 What's in the Ingredients List?