Abstract: The volatile compounds in dried jujube obtained in the temperature range of 80–160 ℃ were characterized by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). The total sugars, reducing sugars, amino acids and color parameters were determined as well to evaluate the effect of drying temperature on jujube quality. A total of 99 volatile compounds were identified by GC-MS, 61 compounds of which were verified as aroma-active compounds by olfactometry. The main compounds, furfural, 5-methyl furfural, 5-hydroxymethylfurfural, 2,3-dihydro-3,5-dihydroxy-6-methyl-4Hpyran- 4-one, furfuryl alcohol, 2-acetylfuran, 3,5-dihydroxy-2-methyl-4H-pyran-4-one, and 1,3-dione-cyclopent-4-ene, were generated at high drying temperature in a temperature-dependent manner. Some acids, such as acetic acid glacial, 2-methyl butyric acid, hexanoic acid, heptanoic acid, octanoic acid, benzoic acid, benzoic acid, and lauric acid, as well as sugar and amino acid contents, were decreased as the temperature increased. Color parameters showed that the browning reaction was enhanced, leading to a burnt flavor when the temperature was over 140 ℃.

Key words: gas chromatography-mass spectrometry-olfactometry (GC-MS-O), jujube, drying, reducing sugar, amino acid, color