wunder beta

🫒 Olive oil: pressing, polyphenols and extra virgin

You swallow, and the oil bites the back of your throat. That sting is the grade. Extra virgin is a panel and a percentage, not a compliment.

5
lessons
~20 min
to learn
🔬 Science
subject
Adults
level
Start the course →

What you’ll learn

  1. The fruit you crushTreat olive oil as the juice of a stone fruit, Olea europaea, whose fat sits in the flesh and whose colour is a ripeness clock.A drupe, not a seed. Green and black are ages. The mill wants the fruit within two days.
  2. The mill that barely pressesFollow crush, malaxation and decanting, and retire 'first cold pressed' except as the EU's hydraulic-press phrase below 27°C.Paste, knead at 25–30°C, spin. Spain's mills are mostly two-phase. The press is a museum word.
  3. What extra virgin actually meansUse IOC acidity and sensory rules, separate virgin from lampante and refined blends, and read the 2010 UC Davis failures as rancidity more than as 'fake'.≤0.8% acidity, zero defects, some fruit. Sixty-nine percent of those imported shop samples failed the name.
  4. The pepper is chemistryName oleocanthal, oleuropein and the phenol range, and treat bitterness as a harvest and mill decision.Beauchamp's ibuprofen analogue. Early fruit, cool malaxation, two-phase spin. Typical phenols 100–300 mg/kg.
  5. The bottle on the counterStore oil like a juice, retire the smoke-point scare, and send the reader to a tasting spoon and a harvest date.Dark glass, 15–18°C, use it once opened. Tonight, taste for fruit and pepper. Ask what the window did.

Questions this course answers

Where in the olive does the oil actually sit?

An olive is a drupe. The oil is in the flesh. That is why a mechanical mill can make virgin oil without solvent extraction.

Put a modern virgin mill in the order AOCS describes

AOCS: crush, malax 30–75 min, horizontal decanter, then a 6000–7000 rpm vertical polish. Pressing is optional and uncommon.

The IOC extra-virgin ceiling on free acidity.

Vossen after the IOC: extra virgin ≤ 0.8%, virgin ≤ 2%, lampante above 3.3% or ruined on the nose.

In the 2010 UC Davis / Australian study, about what share of imported supermarket samples labelled extra virgin failed international extra-virgin standards?

Bailey, reporting Flynn: 69% of imported samples failed, versus 10% of the California samples. Many failures were rancid or oxidised, not proven seed-oil fakes.

Match each name to what the papers actually give it

Beauchamp on oleocanthal; Pedan on oleuropein and its children; AOCS on malaxation; Vossen on lampante.

Under EU Regulation 29/2012, when may a bottle say 'first cold pressing'?

Article 5: 'first cold pressing' is reserved for virgin grades from a hydraulic press below 27°C. Centrifuged oil may say 'cold extraction' at the same temperature.

Grounded in trusted sources

  • [object Object]
  • [object Object]
  • [object Object]
  • [object Object]
  • [object Object]
  • [object Object]

Every Wunder lesson is built from real, reputable sources — never invented.

Related Science courses

🫒Olive oil: what extra virgin means🍯Honey: supersaturation, crystallisation and why it never spoils🍵Tea: oxidation, terroir and six categories🍺Beer and bread: the same organism, two civilisations🫘Miso, soy and koji: East Asia's mould🥒Pickling vs fermenting: two ways a cucumber lasts🌡️Food safety by temperature: the danger zone🫧Whipping: foam, protein networks and copper bowls

Wunder is a personalized learn-anything platform — tell it any topic and it builds a beautiful, fact-checked course in minutes, with narration, a knowledge check, and a college-style University track.

Browse more Science courses · All topics · Home

© 2026 Wunder Learning LLC · Terms & Privacy