Evolution of Virgin Olive Oil during Long-term Storage

Area of Science:

• Food Science
• Agricultural Chemistry
• Olive Oil Quality

Background:

• Virgin olive oil quality is influenced by storage conditions.
• Understanding the long-term effects of temperature on oil stability is crucial for producers and consumers.

Purpose of the Study:

• To investigate the evolution of virgin olive oil quality from four varieties under different storage temperatures (5°C, 10°C, 20°C) over three years.
• To assess the impact of storage temperature on key quality parameters and oxidative stability.

Main Methods:

• Four virgin olive oil varieties were stored at 5°C, 10°C, and 20°C for up to 3 years.
• Quality parameters including free acidity, peroxide value, K270, K232, oxidative stability, and color indexes were monitored periodically.

Main Results:

• Free acidity increased but remained below the extra virgin olive oil (EVOO) limit.
• Peroxide values and K-values exceeded EVOO limits in some samples stored at 20°C after 28 months.
• Oxidative stability decreased by 38%-50%, and color indexes increased due to pigment degradation.

Conclusions:

• Storage temperature significantly affects virgin olive oil quality over time.
• Temperatures of 20°C can lead to a loss of extra virgin olive oil status within three years.
• Proper storage conditions are essential to maintain virgin olive oil quality and shelf life.