Random question on fuel observation


New Member
May 7, 2021
Grabbed some samples of fuel from the gas station for ethanol content testing yesterday and noticed that the e85 (actually e90) is almost the same color as the 91 octane (e10), and the 100 octane (somewhere between e5-e10) is much yellower. Is this just because of dye? Haven't really actually looked at gas in many many years, but seems I remember it all used to being a yellower color similar to the 100 octane in this pic.

Was just curious on this, not that it actually means anything.