Optimization of malaxation process of virgin olive oil using desired and undesired volatile contents

• Desired and undesired aromas of olive oil are eligible responses in optimization.
• Response surface methodology is a suitable tool towards objectives in this study.
• Major compounds were trans-2-hexen-1-al and hexanal in desired aroma transition.
• Temperature adversely affects the desired aroma transition into olive oil.
• Optimum temperature and time were about ≤29 °C and ≤40 min, respectively.

Volatile aroma composition is one of the most important quality parameters of olive oils and changes depend on the maturity and processing methods. In this study, optimization of the malaxation process by response surface methodology (RSM) was aimed in terms of desired and undesired aroma content of oils from olives at three maturity stages. Aroma profile was determined by the head space–solid phase micro-extraction (HS-SPME) method and gas chromatography-mass spectrometry (GC-MS).A full second-order regression model was proposed for the prediction of optimized process responses. The models for desired and undesired volatiles of olive oils extracted from purple and black, except spotted, olive were found to be sufficient for the successful prediction of experimental results. The optimum conditions of temperature and time pairs to maximize desired aroma content and to minimize undesired ones in oil extracted from purple and black olive fruits were found to be 28 °C/38 min, and 29 °C/40 min, respectively.