Comparative Analysis of Three Types of Peaches: Identification of the Key Individual Characteristic Flavor Compounds by Integrating Consumers' Acceptability with Flavor Quality

In order to recognize the key flavor compounds influencing the consumers' choice for honey peach, nectarine, and flat peach and provide important information for orientation breeding, sugars, organic acids, and aroma volatiles in 3 types of peaches were examined by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) and their key individual characteristic flavor compounds were identified by multivariate analysis integrated with consumers' evaluation. No significant differences in sugar and organic acid were observed between 3 types of peaches. In hierarchical clustering analysis (HCA) and principal component analysis (PCA) models, 3 types of peaches could not be differentiated by sugars or organic acids, but could be identified completely by aroma volatiles or by flavor compounds. A partial least squares regression (PLSR) model revealed that the key individual characteristic volatiles in nectarine, honey peach, and flat peach are C9 compounds and terpenic compounds, norisoprenoids and C6 compounds, and benzaldehyde, γ-decalactone, and δ-dodecalactone, respectively. These results suggest that sugars and organic acids form the background flavor of peach fruit and lactones shape the typical peach aroma. However, the individual aroma volatiles play the decisive role in unique flavor determination of different types of peaches.