A new smart film may help people check meat freshness. “Smart” means the package can give useful information. The film changes color when meat begins to spoil. Spoil means food loses freshness and may become unsafe. Meat releases gases as bacteria grow. One gas is ammonia, which has a strong smell. (kyushu-u.ac.jp)

The film detects these gases. Detect means to find something that is hard to notice. Researchers at Kyushu University recently made a special version. It uses milk protein and color from black soybean skins. The plant color reacts to changes around the meat. The film can also glow under UV light. UV is a kind of light we cannot see. This glow makes small changes easier to notice. (kyushu-u.ac.jp)

For example, researchers tested the film with cold mutton. Mutton is meat from a sheep. After about six days, the film showed a clear glow. It also changed color slowly under normal light. This package is still being studied. Experts must check its safety, cost, and daily use. In the future, it may help reduce wasted meat. People should still follow food dates and safe storage rules. (kyushu-u.ac.jp)