Wheat Middlings

Flour mills separate wheat into flour and other streams. Fine bran, germ and flour particles are blended into middlings, giving mills a feed market for material outside the main flour stream.^5,6

1. 01 // Source Wheat grain Whole grain arrives at a flour mill and is cleaned before the kernel is broken apart.
2. 02 // Process Conditioned and rolled The mill dampens the grain, then passes it through rolls that separate its outer layers from flour.
3. 03 // Process Sifted into streams Sieves grade the broken material, directing flour onward and collecting bran, germ and finer particles.
4. 04 // Process Feed streams blended The mill combines selected leftover streams; the mix changes with the flour it aims to produce.
5. 05 // Output Wheat middlings A dry milling blend enters feed channels and is measured into kibble with the other ingredients.

1. 01

   Supplies starch

   Fine flour particles carry starch into the recipe. Middlings supply less starch and more fiber than wheat grain, so their contribution depends on the mill's blend.^4,5

2. 02

   Adds fiber bulk

   Bran particles add fiber alongside the starch. That changes the recipe's fiber content, although a dog feeding study has not isolated middlings' effect on stool form.^1,4

3. 03

   Uses a mill stream

   Flour production leaves a substantial feed stream. Selling it recovers value, and Kansas State reports that middlings prices sometimes dip relative to their feed value.⁶

How much A yearlong dog comparison fed 13.2% wheat middlings in a mixed diet; it did not isolate this ingredient's effect.¹

1. Vets say

   Wheat can trigger a food allergy

   Evidence

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

   A review found wheat reactions in 38 of 297 dogs already diagnosed with food reactions. Wheat matters for an affected dog, but those selected cases do not tell us how often dogs in general react.³

2. Brands say

   Wheat middlings keep stools firm

   Outruns the evidence

   Evidence

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

   In a yearlong comparison of 24 dogs, the diet containing middlings produced more, wetter feces than a very different diet. Several ingredients changed, so the study cannot assign that result to middlings or prove a firming effect.¹

3. Brands say

   Wheat middlings feed good gut bacteria

   Outruns the evidence

   Evidence

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

   A laboratory test used feces from 4 dogs and found moderate fermentation of middlings. No feeding test showed a change in gut health, so the prebiotic promise goes beyond the result.²

4. Critics say

   Wheat middlings are empty filler

   Outruns the evidence

   Evidence

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

   Feedipedia's samples average about 32% starch, 18% protein and 8% crude fiber on a dry basis. Those components give middlings a job in the recipe, even though the name says little about batch quality.⁴