Comparative Study of Oxidative Stability in Almond and Hazelnut Cultivars Based on Volatile Compound Monitoring

Introduction: Oxidative stability is a critical quality parameter in the food lipid-rich products such as nuts. Oxidation not only reduces nutritional value but also alters the organoleptic profile, leading to off-flavors and aromas that are typically rejected by consumers. Since aroma is a key component of sensory perception, this study focuses on the evolution of the volatile profile of raw almonds and hazelnuts under oxidative stress.

Methods: Two almond cultivars and two hazelnut cultivars were selected. Samples were stored for two months under controlled conditions combining different temperatures and light exposure to induce oxidation. Volatile compounds were analyzed weeckly using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC-MS).

Results: The results showed a time-dependent increase in typical oxidation volatiles. However, the rate and pattern of volatile evolution varied between nut species and among cultivars. Some cultivars demonstrated greater resistance to oxidative changes, with slower accumulation of off-flavor compounds. The data also highlighted the effect of storage conditions in modulating the intensity of oxidation.

Conclusions: This study highlights the importance of considering both nut type and variety when evaluating oxidative stability. Monitoring volatile composition provides valuable insight into sensory deterioration and may guide storage strategies and cultivar selection for improved shelf life and consumer acceptance.