Assessing Volatiles in Three Chinese Dwarf Cherry Cultivars during Veraison and Maturation Using Headspace-Solid Phase Microextraction with Gas Chromatography–Mass Spectrometry

Chinese dwarf cherry is a native shrub in northwest China with a rich and unique fruit aroma. This study aims to determine the changes in volatile profiles during the maturation period, which provides a theoretical basis for the optimal harvest times and the breeding of aroma-rich varieties. The variation in the production of 164 volatile compounds from three Chinese dwarf cherry cultivars, namely, "Jing'ou 1", "Jing'ou 2", and "Jing'ou 3", were investigated by headspace-solid phase microextraction (HS-SPME)-GC-MS. These volatiles mainly constituted alcohols, carbonyls, esters, terpenoids, and hydrocarbons. Their maturation process could be divided into three stages, namely prophase, metaphase, and anaphase. Prophase contained an abundance of hydrocarbons and carbonyls, primarily benzaldehyde being dominant among all volatiles. During metaphase, volatiles remained at a low level of abundance and diversity. Anaphase coincided with full maturation and was associated with esters and terpenoids; in particular, "Jing'ou 3" presented more compound diversity and a high level of acetate esters. The periods including the week prior to veraison and the week during maturation were particularly critical in volatile formation in Chinese dwarf cherries. This study reveals that the low level or lack of hexanal might be one of the distinctive characteristics separating Chinese dwarf cherries from other Cerasus or Rosaceae fruits.