OMM 7: Avocado Oil Woes, EVOO Outperforms, and More On Cooking Oils and Fats

August 4, 2023
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Intro banter

  • John has coffee with RD of North by Northwest Relays.
    • Future relay team event for EP fans?!
  • Update, we are back in a good flow with the podcast these days and receiving wonderful feedback—thank you, grateful!
  • On curiosity and the urge to “dive deeper” in work, research and extracurricular things when life’s big stressors ease up.
  • Fullscript now offering subscriptions for your favorite, most valued supplements—brilliant idea in our opinion! Subscribe and save via EP here.
  • Tawnee still holding strong to her daily routine with Crucial Four Icelandic Sea Salt and MagBicarb. Grab your salt and more now for 10% off here.

Is your avocado oil rancid or unpure?

Research: “First report on quality and purity evaluations of avocado oil sold in the US” (Oct 2020)

  • Currently no standards to regulate avo oil—quality/purity control not there, adulterated oils are a thing.
  • Quality and purity were analyzed (details in article on what this means). 
  • Researchers even made their own avocado oil as a control.
  • 22 samples purchased at a grocery store or online, majors brands though not specified, from extra virgin to refined. 
  • Key findings:
    • Adulteration with soybean oil at levels near 100% was confirmed in two “extra virgin” and one “refined” sample. 
    • The majority of the samples were of low quality with five of the seven oils labeled as “extra virgin” having high FFA values and six of the nine “refined” oils had high PV (measure of oxidation). FFA, PV, and specific extinction in UV data demonstrated that these oils have undergone lipolysis and oxidation, respectively. This likely resulted from improper or prolonged storage, using damaged or rotten fruits, or extreme and harsh processing conditions
  • Only two brands produced samples that were pure and nonoxidized. Those were Chosen Foods and Marianne’s Avocado Oil, both refined avocado oils made in Mexico. Among the virgin grades, CalPure produced in California was pure and fresher than the other samples in the same grade.
  • Personal note: We’ve been avocado oil and products with avocado oil for YEARS! Will rethink what I’m buying.

Smoke point and how extra virgin olive oil stacks up against other cooking oils when heated, etc.

Research: “Evaluation of Chemical and Physical Changes in Different Commercial Oils during Heating” (May 2018)

  • Research study evaluating the efficacy of smoke point and other traits of oils when heated to high temps, for long duration or repeatedly over time.
  • Measured high quality extra virgin olive oil (EVOO), virgin olive oil (VOO), olive oil (OO), canola oil (CO), rice bran oil (RO), grapeseed oil (GO), and coconut oil (CoO).
  • Key findings:
    • “An oil’s stability against oxidation depends not only on the degree of unsaturation, but also on the antioxidant content present in the unsaponifiable fraction [25].”
    • “Canola oil demonstrated a rapid increase in polar compounds from 150C to 240C (Figure 6), with its highest value of polar compounds (27,5%) above the limits permitted for human consumption, followed by grapeseed (19,3%) and rice bran (13.0%) oils.”
    • “Extra virgin olive oil (EVOO) and other common cooking oils were heated up to 240C and exposed to 180C for 6 hours, with samples assessed at various times, testing smoke point, oxidative stability, free fatty acids, polar compounds, fatty acid profiles and UV coefficients. EVOO yielded low levels of polar com- pounds and oxidative by-products, in contrast to the high levels of by-products generated for oils such as canola oil. EVOO’s fatty acid profile and natural antioxidant content allowed the oil to remain stable when heated (unlike oils with high levels of poly-unsaturated fats (PUFAs) which degraded more readily). This study reveals that, under the conditions used in the study, smoke point does not predict oil performance when heated. Oxidative stability and UV coefficients are better predictors when combined with total level of PUFAs. Of all the oils tested, EVOO was shown to be the oil that produced the lowest level of polar compounds after being heated closely followed by coconut oil.”
  • We are focusing more on animal fats for cooking: local raw grassfed butter, grassfed tallow, pork lard and duck fat.

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