A rainbow sheen on your ham: Safe to eat or cause for concern?
Cold cuts are a popular sandwich addition, and many people enjoy adding ham to scrambled eggs, omelettes, and casseroles. Sometimes, however, a rainbow sheen can appear on the surface of the meat, reminiscent of gasoline stains. What does this mean, and is such a cold cut safe to eat?
Some cold cuts, purchased by weight or in packages, can exhibit a rainbow colour on the store shelf. Even those prepared at home can look similar. Many wonder if this effect means the cold cut is unappetizing or spoiled, causing them to worry about eating it.
How to choose a good cold cut?
Cold cuts are a source of protein, but they can also contain fat, salt, and preservatives, which can adversely affect health. Therefore, they should not be the foundation of our diet. If you can't imagine a sandwich without ham, pay special attention to the quality of the product you choose.
The best choices are cold cuts with a high meat content—at least 80%. The higher the meat content, the fewer artificial additives. Cold cuts with a composition of around 50% are more like meat substitutes. Choose those made from 120 g of meat per 100 g of product and smoked with natural smoke.
You can also prepare cold cuts yourself at home. You can opt, for example, for roasted loin. This way, you have full control over the quality.
Rainbow sheen on cold cuts
This phenomenon, which we can observe in many food products, especially meat and cold cuts, has a scientific basis. The rainbow sheen arises from light diffraction. When light falls on the surface of the meat, it reflects off its muscle fibres and proteins, creating a rainbow spectrum of colours. Cold cuts with a rainbow sheen are safe to consume.
During cutting, the muscle fibres become rearranged. The light that falls is refracted in a specific way, allowing us to see a rainbow effect on the surface of the cold cut. The natural structure of muscles, composed of many thin fibres, acts like a prism, splitting the light into individual colours. The thinner the slices, the greater the chance of seeing a rainbow sheen because light has a larger area to reflect. Salt, nitrates, and nitrites used in curing meat can enhance this effect by preserving the meat's structure and increasing the intensity of light reflection.
