Corn Germ Meal

Corn mills separate the oil-rich germ while making starch, flour or other corn products. Extracting the oil leaves solids that mills sell for feed. Bran and starchy fragments can join those solids.⁵

1. 01 // Source Whole corn The germ is separated from the rest of the kernel during wet or dry milling.
2. 02 // Process Germ separated Wet mills wash and dry the germ; dry mills separate it from bran and the starchy center.
3. 03 // Process Oil extracted Mills press out corn oil and may use a solvent to extract more from the germ.
4. 04 // Output Corn germ meal The remaining dry material goes to feed plants with varying amounts of oil, bran and starch.

1. 01

   Adds plant protein

   Oil extraction leaves protein in the meal, which contributes to a food's crude protein figure even though its amino acid balance is weak and needs other ingredients to cover the gaps.^3,5

2. 02

   Supplies starch and fiber

   Kernel fragments bring starch and fiber into the recipe. In one small dog trial, diets containing corn germ produced drier feces than the control diet.^1,5

3. 03

   Sells the milling leftover

   Oil extraction already leaves these solids. Selling them for feed gives mills another outlet; Feedipedia describes corn germ meal as a commodity traded worldwide.⁵

4. 04

   Carries added liquids

   The meal absorbs liquids such as fat, which lets a feed maker distribute liquid ingredients through a dry mix.⁵

How much A 6-dog crossover trial fed test diets with 20% whole or defatted corn germ, each with and without an added xylanase enzyme.¹

1. Brands say

   Corn germ meal adds useful protein

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   A model applying pig and rooster digestibility data to NRC adult dog requirements scored corn germ meal's protein quality at just 17, 33 and 37 out of 100 across three literature sources, limited each time by tryptophan or sulfur amino acids. Those are low-quality scores, so calling the protein simply useful overstates it.³

2. Brands say

   Its fiber keeps a dog's stool firm

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   In a 6-dog crossover trial, diets containing whole or defatted corn germ produced drier feces than the control diet. The trial used 20% germ and did not test whether smaller amounts improve stool health.¹

3. Critics say

   Corn germ meal is just filler

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   Feedipedia reports protein, starch and fiber in the extracted meal. An 8-dog study also measured usable energy from corn germ, although it did not identify that product as extracted meal. Calling corn germ ingredients nutritionally empty is wrong.^2,5

4. Owners say

   Corn ingredients trigger most dog food allergies

   Outruns the evidence

   Evidence

   1. Strong
   2. Some
   3. Thin
   4. None

   A review found corn reactions in 13 of 297 dogs with reported food reactions, fewer than for beef, dairy or chicken. Those cases cannot measure risk for every dog and did not test corn germ meal separately.⁴