Brewers Rice

Rice mills remove the hull and bran to produce polished rice. Some kernels break during milling. Screens separate the smallest pieces from intact kernels, creating a distinct stream for buyers including pet food makers.^5,6

1. 01 // Source Whole rice Rice arrives at the mill with a hull around its bran and starchy center.
2. 02 // Process Hulled and polished The mill removes the hull and outer layers to make white rice.
3. 03 // Process Screened by size Milling breaks some kernels; screens separate the small fragments from larger pieces.
4. 04 // Output Brewers rice The separated fragments go to buyers including pet food makers, without going through a brewery.

1. 01

   Calories the dog actually absorbs

   Broken rice is mostly starch. In an 8-dog trial, dogs digested about 90% of its dry matter, yielding 13.1 MJ of metabolizable energy per kg as fed.^1,4,8

   1. Strong
   2. Some
   3. Thin
   4. None
2. 02

   Little fiber, so little stool bulk

   Brewers rice digests almost completely and carries little fiber, so less material reaches the colon. Dog trials show high digestibility and less wet stool as rice replaces corn.^2,4,8

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

1. 01

   Supplies digestible energy

   The ingredient is mostly starch. In a dog trial, diets based on brewers rice ranked among the most digestible for dry matter and energy.^1,4

2. 02

   Helps form kibble

   Starch cooks during extrusion and helps the finished kibble hold together. Brewers rice supplies that starch while contributing little fiber.^4,7

3. 03

   Uses a milling stream

   Mills sell small broken kernels separately from intact rice. Feedipedia says most broken rice in the United States goes to pet food, though it is relatively costly for livestock feed.⁵

How much A dog feeding trial tested diets containing 15.7 to 59.6% brewers rice as it replaced corn; those tested amounts are not typical recipe amounts.²

1. Brands say

   Dogs digest brewers rice very well

   Evidence

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

   In a randomized 36-dog comparison, brewers rice and cassava diets led for dry matter and energy digestibility; starch digestion exceeded 98% across diets. A separate rice-for-corn feeding trial also found digestibility rose as rice increased.^1,2

2. Brands say

   Brewers rice makes smaller stools

   Evidence

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

   A 5-week feeding trial replaced corn with increasing amounts of brewers rice and recorded less wet stool as rice increased. It studied healthy beagles, so the result does not show that rice treats diarrhea.²

3. Brands say

   Brewers rice soothes sensitive stomachs

   Outruns the evidence

   Evidence

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

   The dog studies measured digestion and stool output in healthy animals, not recovery from digestive disease. Brewers rice digested well in the 36-dog comparison, but that does not show it treats a sensitive stomach.^1,2

4. Brands say

   Brewers rice releases sugar slowly

   Outruns the evidence

   Evidence

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

   The 36-dog trial found larger early glucose and insulin responses on brewers rice, corn and cassava diets than on the pulse diets. Selling brewers rice as a slow glucose source reverses that result.¹

5. Critics say

   Brewers rice is just cheap filler

   Outruns the evidence

   Evidence

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

   Dog feeding trials show digestible energy and less stool as brewers rice replaces corn. Feedipedia also describes broken rice as costly enough to limit livestock use. It has a clear job, whatever a mill charges for it.^1,2,5

1. 2008 // Feeding trial, 6 starch sources

   Brewers rice tied for best digestion but raised sugar early¹

   36 dogs, 6 per diet

   Found. Brewers rice and cassava diets led on dry matter and energy digestibility. Starch digestion topped 98% on every diet, but brewers rice, corn and cassava produced larger glucose and insulin rises within the first 30 minutes.

   What it means. A rice-heavy kibble delivers efficient calories. It does not deliver the slow, steady sugar release some labels imply.

2. 2010 // Digestibility trial, 7 ingredients

   Broken rice matched sorghum as a digestible grain⁸

   8 adult dogs in metabolism cages

   Found. Fed at 30% of a reference diet, broken rice had 90.5% dry matter digestibility, tied with sorghum and far above rice bran at 55%. It supplied 13.1 MJ of metabolizable energy per kg as fed.

   What it means. Broken rice is an efficient energy grain. Rice bran is a different ingredient that supplies fewer usable calories.

3. 2015 // Feeding trial, 9 diets

   Rice kept its digestibility even when ground coarser⁹

   54 beagles, 6 per diet; the abstract does not name the rice type

   Found. Rice, corn and sorghum were each ground to about 300, 450 and 600 microns. Coarser grinding cut digestibility for corn and sorghum; for rice it lowered only energy digestibility at the largest size.

   What it means. Rice-based kibble is forgiving to make. Grind size matters less for rice than for corn or sorghum.

4. 2020 // Hair sample comparison

   Dogs eating rice diets carried more arsenic in hair³

   16 dogs: 7 on rice-based diets, 9 eating no rice

   Found. Dogs on rice-based diets averaged 0.143 micrograms per gram of inorganic arsenic in their hair, against 0.086 in dogs eating no rice. The study did not measure illness or name the rice ingredient.

   What it means. This shows exposure, not harm. If one rice-heavy food is all your dog eats, ask the maker about arsenic testing.