Tren is golden in crystalline form, and this is also stated in the Merck Index as well. By "bleaching" the tren, it would just be adding extra steps, which equal more costs, which is something that if even possible, would not make sense.
Using something such as cottonseed oil compared to grapeseed oil would lighten the golden color, but there should still be some golden color...unless you dilute it a ton.
In the past while using Fina pellets, the methylcellulose would decompose and turn the golden color darker, sometimes a red color for some if they used very old pellets which had been placed in temps above room temp for long periods of time.
