We covered a little bit about Can Extra Virgin Olive Oil Go Bad? last week, and this week we will look at the second part of this as Can Olive Oil Expire?

What Happens When Olive Oil Expires

First of all. it’s good to understand what is in extra virgin olive oil in the first place.  Besides the oil squeezed without additional processing in the case of extra virgin olive oil, numerous polyphenols are extracted in the process.  We explain in detail about the specific polyphenols in olives which are phenolic polyphenols and are more rare than the more common flavenoid polyphenols.  The polyphenols from olives are very high in anti-oxidants, anti-inflammatory agents and vitamin C and E.  These agents can protect the body’s cells and tissue against chronic oxidative stress that can ultimately cause cardiovascular diseases, joint diseases, neurological and immunological diseases as well.*  And some of the most powerful natural ingredients of these polyphenols are hydroxytyrosol, tyrosol and oleocanthals which make up 90% of the polyphenols in olives.

So, these elements of your olive oil typically expoire but they are still there – just in lower dosages than stated on the bottle.  However, what emerges when olive oil becomes rancid?

What Are these New Ingredients?

First of all, it is well accepted that rancid olive oil will not hurt you.  It might ruin your next great food dish – but the oil itself will not hurt you.  The smell of being rancid seems to be caused by the emergence of three primary compounds: Nonanal, Hexanal, and Pentanal.  Nonanal is found naturally in grapes and oats and is not toxic unless consumed at extremely high levels.  Hexanal is also not considered toxic at any normal levels. and finally, Pentanal is actually used for food flavorings and is also considered safe at normal levels.

What About the Effect on The Polyphenols?

Unfortunately, time can really diminish the power and level of the polyphenol active ingredients in extra virgin olive oil.  We estimate that the molecule of hydroxytyrosol can diminish by as much as 25% in a year while sitting on the shelf.  For this reason, we put in extra, enriched olive polyphenols in our olive oils and supplements.  Many olive oil producers will claim to have high levels of polyphenols in their products, but we like to show you what levels of hydroxytyrosol or tyrosol will be in the products even after their shelf life expires.  This requires us to formulate our TrePhenol® polyphenols with as much as 3x the levels listed on the labels at the time of bottling. Our independent lab tests of some competitor products showed they didn’t have the levels of hydroxytyrosol or tyrosol even after 6 months from bottling as their label indicated.

Why this matters is because the European Food Safety Authority (EFSA) has determined that a minimum 5 mg of hydroxytyrosol and its derivatives in olive oil should be consumed daily by individuals – or to be used by olive oil producers to use a cardiovascular health claim.  EFSA is similar to the Food and Drug Administration (FDA) here in the U.S.

So Now You Know…

So now you can rest easy with your olive oil that might be old or rancid.  For what to do with expired olive oil look here, and to find out more about the differences between extra virgin olive oil and polyphenol rich olive oil check here.

References

Healthline “Does Olive Oil Go Bad”  https://www.healthline.com/nutrition/does-olive-oil-go-bad#:~:text=Effects%20of%20consuming%20rancid%20olive,potent%20antioxidant%20properties%20(%202%20).

“Changes induced by UV radiation during virgin olive oil storage”  at https://pubmed.ncbi.nlm.nih.gov/16787029/

Actual EFSA determination document here: https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2012:136:0001:0040:en:PDF

* Disclaimer: These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.