Sirius, F/A-22 does not exist anymore. It's been 13 years already since its extinction.
Regarding the afterburner blueish flame, there is nothing secret about it :) It has a blueish/purple flame due to the combustion temperature and efficiency. Generally speaking, the russian engines have this characteristic, due to the bypass ratio and higher amount of O2. The flame is hotter and more efficient simply because it has more oxygen available. In this case, though, the engine is on the testbench, being run in a cell with a limited amount of light, if you go outside and run the engine in full AB, you'll see the color changing to yellow. But most of the time, regardless the efficiency and temperature of the afterburner, they will always look blueish at night/ambients with a limited amount of light.
Take a look at the AL-31 turbofan family, especially the ones mounted on Su-30s. They are blueish, they look stunning.
But the best one has to be the Tu-22; It has to be the most beautiful and most efficient afterburner ever! :)
If the F-35 had a blue afterburner, it would be amazing too.
Keep in mind that this has nothing to do with fuel!