What is the difference between yellow and brown grease? Submitted by an Anonymous Greaser on Thu, 2010-12-02 21:00 What is the difference between yellow and brown grease? Reply to this post FFA Submitted by an Anonymous Greaser on Fri, 2010-12-03 14:05 FFA reply ones yellow, ones brown LOL Submitted by an Anonymous Greaser on Mon, 2010-12-06 03:10 ones yellow, ones brown LOL reply yellow grease is used cooking Submitted by an Anonymous Greaser on Wed, 2010-12-15 23:23 yellow grease is used cooking oil agregated and often contains rendered animal fats (tallow, lard, poultry, etc) depending on the rendering company collecting and rendering the grease. Smaller collection and "rendering" or processing companies don't typically render in animal fats. FFA averages are 5-9% with low's of 2 and high of 15% to be considered yellow grease (in spec). Brown grease on the other hand, is grease and drain water and junk that goes down the drain and is caught in a large "trap" before it gets into the sewer. The grease, food and other gunk builds up in the trap and has to be pumped out. The scum of grease and junk floating on the water is brown grease. nasty stuff and not at all the same as yellow grease. FFA is typically 50% on low side to 90%+ on high side, and it STANKS! reply Reply to this post Your name Comment * Location * What code is in the image? * Enter the characters shown in the image.