Indigo carmine 0.25%, a water-soluble blue solution, finds frequent application in food histology. It has a wide range of applications, especially in the study of seafood and dairy products. Thanks to its ability to bind proteins and other complex macromolecules, it allows detailed visualization of structures in crustaceans such as shrimp and crab, as well as in cheese and other dairy products. This ability allows accurate assessments of the quality and freshness of these foods.

The solution consists of indigocarmine (C.I.: 73015, CAS No.: 860-22-0) in water. The dye indigocarmine belongs to the group of indigoids and provides an intense blue coloration. Although its chemical properties allow it to bind to a wide variety of macromolecules, it is not specific and therefore cannot be used to identify specific molecules.

The application of indigo carmine 0.25% solution may yield different results depending on the food being tested and its specific composition. In any case, the solution provides a clear contrast and improved visibility of the structures under investigation, facilitating the analysis and evaluation of the food samples.