Why is there a luminous orange hue in this piece of tuna?
I just sliced this piece of tuna that had been in my freezer for about a week and had been thawed in the refrigerator for a day - to find this luminous orange colour to it. It was on the outside of the slice too but not as much.
This is from the supermarket and I have no idea how long it had been sitting in their refrigerator, although they claim that their product is fresh.
Is this some kind of unusual preservative or maybe the fish has gone bad?
Best Answer
From Cooks Illustrated
The rainbow effect is caused by the reflection of light off muscle fibers, technically known as double refraction or birefringence. It occurs when the muscle fibers are cut crosswise and can be observed for several days after slicing the meat. Light striking the ends of the fibers is reflected in two different directions, appearing to the eye as a rainbow of colors. Just like a real rainbow, the multicolor appearance is fleeting, visible only when the muscle fibers are cut at a specific angle relative to the grain of the meat and when the meat is viewed at a certain angle.
One more point to keep in mind: While the rainbow effect is harmless and doesn’t offer any indication of how fresh the meat is, there is another color change that is a sign of meat that has passed its prime: the development of a green pigment. Meat with a green cast is contaminated with bacteria and should be avoided.
Pictures about "Why is there a luminous orange hue in this piece of tuna?"
Why is part of my tuna orange?
If the product is overcooked it will looked scorched (orange(y) color). Also, If the tuna meat appears to be orange, this is commonly a natural color variance for albacore tuna. This typically occurs when there is a higher concentration of sugar in the meat, and the sugar becomes caramelized when cooked.What causes Rainbow in tuna?
What causes the shiny, rainbowlike appearance on raw tuna and beef? The rainbow effect is caused by the reflection of light off muscle fibers, technically known as double refraction or birefringence. It occurs when the muscle fibers are cut crosswise and can be observed for several days after slicing the meat.Is oxidized tuna safe to eat?
Tuna tends to oxidize quickly, which cause it to turn an unappetizing grey or brown. Even though it may still be relatively fresh at that point, no one wants to eat it because of the way it looks. That's where the practice of gassing comes in.Why is my tuna bright pink?
Bright red or pink tuna means it has been gassed. In its natural state, fresh tuna is dark red, almost maroon, sometimes even chocolatey looking. Don't worry, you most likely will have no ill effects from eating gassed tuna, according to the FDA.TUNA! Catch, Clean, Cook and EAT!!!! Gabriella's Quepos, Costa Rica
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