What color does the solution turn if lipids are present when testing with Sudan Red?

When testing for the presence of lipids using Sudan Red, the solution turns red if lipids are present. Sudan Red is a fat-soluble dye that selectively stains lipids within the sample. This happens because the dye dissolves in the lipid molecules, leading to a visible color change that indicates the presence of fats or oils. The staining process helps to visually confirm the presence of lipids in the testing sample. Therefore, the formation of a red hue is a clear indication that lipids are indeed present.