VIS spectroscopy and pressure induced phase transitions – Chasing the olive oils quality

• Quality of olive oils has been examined.
• Five oil olives have been investigated in high pressure range 0.1–400 MPa.
• Intense of transmitted and scattered light versus pressure have been examined.
• Fluorescence and absorption spectrum have been analysed.

This paper presents establishing a new protocol of quality assessment of olives oil. Five oil lives have been investigated in high pressure range 0.1–400 MPa and at room temperature. Absorption and fluorescence spectrum have been analysed. As a result of applied pressure, a phase transition of the olive samples has been observed. Five olive oil samples were analysed: Californian extra virgin olive oil, Italian extra virgin olive oil, 2 years old pomace oil and degraded extra virgin oil. The samples were pressurized in cylindrical beryllium copper vessel with two different compression rates. While compressing the transmitted and the scattered light intensities were recorded. Shape of intensities profiles registered versus pressure depended readily on quality of examined sample. Measured kinetic of samples solidification processes could distinguish between different types and assess the quality of the oil.