Rainbow prism: The science behind colourful cold cuts
Cold cuts are a popular sandwich addition and complement scrambled eggs, omelettes, and casseroles well. However, at times, a rainbow-like sheen appears on their surface, resembling petrol stains. What does this indicate, and is such a cold cut safe to consume?
Some cold cuts, whether in bulk or packaged, can take on a rainbow colour in the shop. Even those prepared at home can exhibit this appearance. Many wonder if this effect suggests the cold cut is unappealing or spoiled, causing concern about eating it.
How to choose a good cold cut?
Cold cuts are a source of protein, but they often contain high levels of fat, salt, and preservatives, which can be detrimental to health. Therefore, they should not serve as the mainstay of our diet. Consider the product's quality if you can't imagine a sandwich without ham.
The best choices are cold cuts with a high meat content—at least 80 per cent. The higher the meat content, the fewer artificial additives. Cold cuts with a composition of around 50 per cent resemble meat substitutes more closely. Opt for those made from 100 grams out of 120 grams of meat and smoked with natural smoke.
You can also make cold cuts at home. Consider preparing roasted loin, for example. This way, you can completely control the quality.
Rainbow sheen on cold cuts
This phenomenon, observable in many food products, especially meat and cold cuts, has a scientific explanation. The rainbow sheen results from light diffraction. Light on the meat's surface reflects off its muscle fibres and proteins, creating a rainbow spectrum of colours. Cold cuts with a rainbow sheen are safe to eat.
During cutting, the muscle fibres are arranged in a new manner. The light that falls is refracted specifically, allowing us to see a rainbow effect on the cold cut's surface. The natural muscle structure, composed of many thin fibres, acts like a prism, splitting the light into individual colours. The thinner the slices, the greater the chance of observing a rainbow sheen because the 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.
