Not all olive oils are the same. From pomace to olive oil to extra virgin olive oil, US and International Standards require a variety of analyses for quality and grade. Read on for the different tests performed and how Healthy Harvest oils stack up.
Free Fatty Acid Content is commonly called the “percent
acidity” or “free acidity percent”. High values are a rough
indicator of poor fruit quality or improper handling prior to
milling. Free acidity arises with the hydrolytic breakdown
of the oil. Free Acidity is measured as percent (%) free
fatty acids expressed as oleic acid, the predominant fatty
acid in olive oil.
Peroxide Value is a rough indicator of the amount of
primary oxidation within the oil. A high value indicates
that the olive fruit or paste was likely handled improperly.
Olive oil with high peroxide value may not keep well.
Peroxide is measured by a quantitative chemical analysis
and is expressed as milliequivalent of free oxygen per
kilogram of oil (meq O2/kg).
HH Greek: 7.95
HH True Tuscan:9.49
Ultraviolet (UV) absorbency is an indicator of oxidation,
especially in oils that have been refined. Measured with a
spectrophotometer, the value of UV light absorbance at
different wavelengths indicates the quantity of oxidized
compounds present in the oil. Pomace and refined oils
have higher values than virgin oils.
Total Phenol is the aggregate measure of polyphenol
content in the olive oil or fruit. As polyphenols are a key
antioxidant component in olive oil, Total Phenol is an
indicator of the oil’s potential shelf life, its style and
health benefits. Total Phenol in olive fruit before harvest
can help select optimal harvest time to maximize
polyphenol content in oil. Total Phenol is normally
expressed as milligram equivalent of Gallic (or Caffeic)
acid per kilogram of oil (mg/kg).
HH Greek 140 mg/kg
HH True Tuscan: 441 mg/kg
Oleuropein and Hydroxytyrosol: these two polyphenols
are the most abundant and have also been claimed to
confer the health benefits of olive oil.
Fatty Acid Composition: this is the detailed breakdown
of the fatty acids present in the oil, which may help
distinguish olive oil from other oils.
Diacylglycerols (DAGs) measure the proportion of 1,2
diacylglycerols in the oil, that decreases with storage,
overtime. It correlates inversely with the starting FFA
content of the oil after milling.
Pyropheophytin (PPPs) are the natural products of
chlorophyl decomposition occurring during storage, and
when oil is exposed to elevated temperatures, as in
Sensory Analysis is the evaluation of an oil’s
organoleptic attributes, which are appreciated through
the senses of smell and taste. Sensory analysis is an
essential part of evaluating olive oil quality.
HH Greek: mild, buttery, slightly grassy
HH True Tuscan: robust, peppery