Effect of narrow wavelength bands of light on the production of volatile and aroma-active compounds in ultra high temperature treated milk

Ultra high temperature treated milk (2%), exposed for 7 h at 10 °C to light of 200–400, 395, 463, 516, 567, 610 nm, or full light, was tested for volatile and odor-active compounds using gas chromatography and gas chromatography olfactometry. Exposure to ultraviolet wavelengths (200–400 and 395 nm) and full light produced the highest concentrations of volatile compounds. Exposure to 610 nm produced pentanal and an unidentified compound in high concentrations. Aroma-active compounds produced upon exposure to 516, 567, or 610 nm had relatively short retention times and low aroma intensities. Aroma-active compounds produced upon exposure to 200–400, 395, or 463 nm had relatively long retention times and slight to medium aroma intensities.