*3.2. Odor Fingerprint of Volatile Substances*

The fingerprint of VOCs corresponding to each sample with different irradiation intensities is displayed in Figure 1E. The same row represents the signal peaks of volatile compounds in the same turmeric volatile oil sample, and the same column represents the signal peaks of the same volatile compound in different turmeric volatile oil samples. The color from light to dark indicates the content of volatile compounds from low to high. The fingerprints of volatile organic compounds collected from three kinds of samples were divided into three regions with different colors. The volatile organic compounds in turmeric volatile oil varied substantially with different irradiation intensities.

The substances in the green box in Figure 1E, such as citronellol, alpha terpineol, decanoic acid, methyl decanoate, and linalool-m, have the highest content in JH-1 sample and gradually decrease with the increase in irradiation dose. The content of substances in the yellow area is the highest in JH-2 samples, such as 2,5-dimethylfuran, acetate, and (E)-2 pentanal. The content of substances in the red area is the highest in the JH-3 sample and the lowest in the JH-1 sample, such as 2,5-dimethylfuran, acetal, and (E)-2-glutaraldehyde. The JH-2 content of Yellow Zone 2 is the lowest among the three samples, such as 2-acetylfuran, benzaldehyde-d, benzaldehyde-m, furfural-d, furfural-m, and 2-methylbutanoic acid.
