Effect of Heating Temperature on Volatiles of Roasted Laver

Abstract

The effect of the heating temperature on volatile components of roasted lever Porphyra tenera were studied. Volatile components of dried lover and three roasted lavers heated at 140, 200, and 250°C were analyzed by gas chromatography and gas chromatography-mass spectrometry.
Ten, 10, 17, and 18 components from the dried laver and roasted laver heated at 140, 200, and 250°C were identified. As the heating temperature increased, the peak intensity of acetaldehyde, isobutyraldehyde, and isovaleraldehyde increased. Pyrazines and γ-butyrolactone were detected in the roasted laver heated at a temperature above200°C, and the peak of γ-butyrolactone in the roasted laver heated at 250°C was larger than that heated at 200°C.
Even if the heating temperature increased, the peak intensity of hydrogen sulfide, methyl mercaptan and dimethyl sulfide hardly increased.
Therefore the carbonyls, pyrazines and γ-butyrolactone found in the roasted laver seemed to contribute to the roasted aroma.