Abstract:

Aromatic components in different tissue parts such as peel, pulp and core of Granny Smith apple were determined using gas chromatography-mass spectrophotometer (GC-MS) coupled with headspace solid phase microextraction (HS-SPME). A total of 80 aromatic components were identified in extracted samples. Aldehydes, alcohols, esters and olefins were the major constituents in Granny Smith apple. In addition, a significant difference in aromatic components was observed in peel, pulp and core of apple. The aromatic components were rich in peel and 55 kinds of aromatic components were identified in this tissue. A total of 23 esters with relative content of 14.240% were identified and esters were the most predominant group of compounds in Granny Smith apple. The highest content of C6 aldehydes was observed in this tissue part, which exhibited a relative content of 39.515%. Hexyl acetate, cyclobutanol, (E)-hexa-1,4-diene, (3E,5E)-hepta-1,3,5-triene, 3,6-diethyl-3,6-dimethylcyclohexa-1, 4-diene exhibited higher content. Meanwhile, 18 compounds were detected in apple pulp. Totally 4 kinds of alcohols exhibited a relative content of 31.391% and 2-methylbutan-1-ol was up to 94.814%. Propyl propionate and hexyl formate had higher relative content and were characteristic aromatic components of the pulp. Moreover, 30 components including 2 kinds of C6 aldehydes were identified in the core. Totally 4 kinds of alcohols with a relative content of 42.455% were also identified and 2- methylbutan-1-ol and hexan-1-ol were up to 96.639%. Among these aromatic components from different tissue parts of Granny Smith apple, propyl propionate and hexyl formate were mainly distributed in apple pulp; 2-methylbutan-1-ol was mainly generated in the core and the pulp; hexan-1-ol was rich in the core and the peel; alpha-farnesene was mainly located in the peel and the core; hexanal and (E)-hex-2-onal had high content in the peel, the pulp and the core.

Key words: Granny Smith fruit, different tissue parts, aromatic component, head-space solid phase micro-extraction (HS-SPME), GC-MS