- The major fatty acid in olive oil tryclyglycerols.
- This monounsaturated fatty acid makes up 55 - 85% of olive oil.
- Higher oleic acid content translates into increase durability and shelf life with greater resistance to oxidation.
Extra virgin olive oil is generally higher in oleic acid than other vegetable fats.
FFA (FREE FATTY ACID)
- A low FFA is desirable.
- Free fatty acid speaks to the condition of the fruit at the time of crush.
- Higher FFA values are indicative of poor quality fruit such as damaged, overripe, insect infestation, high temperatures during extraction or too much time between harvest and crush.
- The primary measurement for rancidity in oil
- A very low peroxide value is desirable.
- Peroxides are formed when oils are exposed to oxygen causing defective flavours and odours.
- Higher values are indicative of poor quality and/or storage conditions.
- The healthful antioxidant substances in olive oil which aid in slowing down the natural oxidative processes.
- Phenolic content decreases over time or when exposed to heat, oxygen or light and is an indicator of freshness.
- Polyphenols in extra virgin olive oil are connected with peppery bitterness and other desirable flavour characteristics.
- Consuming fresh, well made olive oil with high polyphenol content is crucial when looking to obtain the maximum health benefit commonly associated with extra virgin olive oil
- Low values can indicate oxidized oil & sensory defects.
- A useful indicator of fruit quality and acts as a snapshot of olive oil freshness.
- Used as a means to test for refining/deodorizing.
- Also an indicator of the age of an oil
- This test was developed to measure the degradation of chlorophyll in olive oil.
- This degradation of chlorophylls to pyropheophytin was found to take place at a predictable pace, making it possible to gain information about the age of an olive oil.
- The rate at which the degradation occurs can be accelerated by even short periods of high temperatures
- A useful indicator of the presence of deodorized olive oils or soft column refining.