EVOO Chemistry
EVOO Chemistry
OLEIC ACID
- 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.
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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.
PEROXIDE VALUE
- 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.
POLYPHENOLS
- 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
DAG (DIACYLGLYCEROLS)
- 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
PPP (PHEOPHYTINS)
- 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.