Origin-Associated Variation in Volatile Profiles of Commercial Sour Jujube Pulp

Sour jujube (Ziziphus jujuba Mill. var. spinosa) is an ecologically and economically important fruit widely utilized in the functional food industry. However, the geographical variation in its volatile flavor profile and the potential odor relevance of individual volatile features remain insufficiently understood. In this study, volatile profiles of commercial sour jujube pulp samples labeled as originating from eight representative geographical regions across China were characterized using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of 1296 putative volatile annotations were obtained, including esters, aldehydes, alcohols, acids, ketones, terpenoids, hydrocarbons, and other compounds. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) revealed distinct distribution patterns among several sample groups. The OPLS-DA model showed acceptable internal validation performance, with cumulative R²X, R²Y, and Q² values of 0.967, 0.891, and 0.811, respectively. Medium-chain fatty acid ethyl esters, including ethyl dodecanoate, ethyl decanoate, and ethyl octanoate, contributed strongly to the multivariate differentiation of SDDY samples. Odor activity value (OAV) analysis further indicated that volatile abundance was not necessarily proportional to predicted odor contribution. Several trace volatile features with low reported odor thresholds, such as 1-nonen-3-one, 2-methoxy-3-(2-methylpropyl)pyrazine, and benzenemethanethiol, showed high calculated OAVs and may be important aroma-relevant candidates. Overall, this study provides an integrated volatile-profiling and OAV-based approach for characterizing compositional differences among commercial sour jujube pulp samples from different reported origins. Because the samples were commercially sourced and no independent external validation or direct sensory evaluation was performed, the results should be interpreted as exploratory evidence of origin-associated differentiation rather than as a validated geographical authentication system.