HS-SPME-GC-MS-based chemometric analysis reveals dose-dependent changes in volatile compounds of gamma-irradiated halloumi-type cheese

Gamma irradiation is widely used to improve the safety and shelf life of dairy products. However, its impact on the volatile composition of Halloumi-type cheese remains unclear. This study evaluated dose-dependent changes in volatile organic compounds (VOCs) of Halloumi-type cheese following gamma irradiation at 0, 3, 5, 7, and 10 kGy using HS-SPME-GC-MS combined with chemometric analysis. A total of 97 volatile compounds were identified across all treatments, with the number of detected compounds increasing with irradiation dose. Multivariate analyses (PCA, PLS-DA, and heatmap) revealed a clear dose-dependent differentiation among the samples. Despite these changes, numerous volatile constituents, including medium-chain fatty acids, ketones, furans, and lactones, remained detectable across all irradiation levels. Irradiation primarily induced selective chemical modulation, including the disappearance of certain native ketones and the formation of oxidation-related aldehydes and alcohols at higher doses. Among the tested treatments, irradiation at 3 kGy produced the smallest deviation from the non-irradiated volatile profile, whereas higher doses (7–10 kGy) resulted in more pronounced restructuring associated with lipid-oxidation pathways. These findings demonstrate that gamma irradiation modifies the Halloumi-type cheese volatilome in a dose-dependent manner. A more comprehensive evaluation of overall product quality would require additional physicochemical, microbiological, and sensory analyses.