Heptanal

For identification and quantitation of aroma compounds, the following authentic flavor standards were purchased from Macklin Biochemical Technology Co., Ltd., Shanghai, China: methyl valerate (99%), isovaleraldehyde (98%), furfuryl mercaptan (98%), heptanal (97%), hexanal (99%) and 2-butylfuran (98%). Benzyl alcohol (AR, 99%), 1-octen-3-one (98%), 1-octen-3-ol (98%), methyl palmitate (AR, 97%) and benzoic acid (99%) were purchased from Yuanye Bio-Technology Co., Ltd., Shanghai, China. Phenylacetaldehyde (95%) and benzaldehyde (AR, ≥98.5%) were obtained from Sinopharm Chemical Reagent Co., Ltd., Beijing, China. The internal standard, 1-decanol (GC, ≥99.5%), was purchased from Aladdin Biochemical Technology Co., Ltd., Shanghai, China.

Standards were purchased for volatile compound identification. 2-Pentylfuran and trans-3-octen-2-one were provided by Sigma Aldrich (St. Louis, MO, USA). Other compounds, including hexanal, benzaldehyde, octanal, nonanal, heptanal, 3-methylbutanal, propanol, pentanol, hexanol, ethanol, 1-octen-3-ol, 3-methyl-1-butanol, 2-methylpropanol, phenethyl alcohol, acetoin, 6-methyl-5-hepten-2-one, 2,3-butanedione, acetic acid, octanoic acid, pentanoic acid, hexanoic acid, γ-undecalactone, ethyl acetate, hexyl acetate, were provided by Macklin (Shanghai, China).