Why does roast beef look iridescent

Information Knowledge Article. Sliced cooked beef or lunchmeat can have an iridescent color. Meat contains iron, fat, and many other compounds.

When light hits a slice of meat, it splits into colors like a rainbow. There are also various pigments in meat compounds which can give it an iridescent or greenish cast when exposed to heat and processing.

Iridescent beef isn't spoiled necessarily. Spoiled cooked beef would probably also be slimy or sticky and have an off-odor. There has been no specific proof, or even connection, between the usage of phosphates and the appearance of the iridescent areas in the muscles of cooked cured or uncured meats.

Once iridescence is present in a muscle, it can not be removed with any of the processes commonly used for the preparation and cooking of solid muscle meats. Due to the fact that the iridescence is directly associated with the reflectance of light from the meat surface, the color of the meat, it's surface condition, the type of light reflecting from the surface and the angle at which the light is hitting the surface, the condition of the meat will have an effect on the intensity of the iridescence.

Smooth surfaced meats will show iridescence more vividly than meats with rough surfaces, and dark colored meats will reduce the intensity. It is primarily for these reasons that cooked cured meats, whose color is brighter than uncured meats, will show the iridescence more vividly.

The addition of phosphates to curing solutions enhances moisture retention, which allows the surface of the meat to retain a smoother texture. For the record, I cook my pot roast for 3 hours. Not only do you need to season the meat aggressively, you need to do so the night before you plan on cooking it. Season the beef all over. Place the joint fat-side down in the roasting tin and put it on the hob. Sizzle to release some of the fat, then turn the beef in the fat to seal and colour it all over, about 5 mins.

For roasts, the best cuts include rib on the bone or boned and rolled , sirloin, top rump and fillet. Brisket, topside and silverside are good for pot roasts, and stewing and braising steak are good for stews and casseroles. Leave it on. In a way, it's sad that meat rainbows are given a bad rap, especially since diffraction gratings in nature are relatively rare -- and I say this as someone who doesn't eat red meat.

Sure, one can see the the vibrant iridescence of peacock feathers or the milky rainbows of an abalone shell and marvel at the rich tapestry that is nature. But it is under the flourescent light of our grocer's deli section where we can look at a rainbow on a slice of beef and know the natural diffraction grating responsible for it is shared with very few things, including the antennae of seed shrimp, and the shells of animals that haven't lived for hundreds of millions of years.

A rainbow worth Instagramming as much as any other, for sure. Skip to content Site Navigation The Atlantic. Popular Latest.