Luckily I live close to a real olive mill, but there really is no way to know. Plus you have people arguing the vast majority of olive oil sold in the USA is "authentic" for some measure of authentic, which is really hard to discern: https://www.aboutoliveoil.org/the-facts-about-uc-davis-olive...
This feels like another one of those areas where as a consumer following the research and knowing what products are good to buy is almost a full time job.
Obviously make sure you practice responsible laser safety, even for a cheap low-wattage laser.
https://www.physicscentral.com/experiment/physicsathome/fluo...
I was looking around with a 532nm green laser pointer the other day, and found that it was almost totally attenuated when aimed at the red (cheap/fake) nectar in my hummingbird feeder. Further experimentation revealed that orange Gatorade was similarly super-absorbent, while beer was pretty transparent to the green light.
Just bought some Tonda Iblea DOP-certified oil and will be interested to try this! It's subjectively delicious, curious if it's objectively flourescent (and if my everyday supermarket olive oil is not).
Might be something to look into if you have Costco nearby.
One of the interesting things I learned from the honey article was that fraudsters have figured out how to work their way around tests, at least for honey. I wouldn't be surprised if they could do the same for olive oil and other food products. It seems like a cat and mouse game.
Something not mentioned in the article is that testing labs themselves need to be tested, certified, and audited. There have been some scandals in forensic labs where techs have repeatedly falsified test results for decades. This is probably especially a problem when organized crime is involved.
If you are at all interested in food safety, I highly recommend "The Poison Squad", about the foundation of the FDA.[1][2]
Also, just because they fool the particular testing tools that labs use doesn't mean you as a consumer won't have an adverse reaction to whatever it was they put in to the honey.
The problem with adulteration isn't exclusively limited to harmful health effects either. Even if your health would not be adversely affected by the adulterants, you might still want to be certain you're getting is genuine.
Let's say you bought corn syrup while under the impression that it was honey. It might not harm your health any more than any other corn syrup would, but you've still been defrauded, and what you got might not have the same health benefits that honey has (assuming honey has such benefits).
Your purchasing decisions could have an ecological impact too. Effectively subsidizing the growing of corn by mistakenly buying corn syrup will have different ecological consequences than subsidizing the establishment of more bee colonies by buying genuine honey.
That's not to mention the ethical issues of being conned in to giving money to fraudsters versus giving it to honest business people.
We should be able to do the same with modern technology and severely penalize individuals who commit fraud.
With the industrialization of food we (as a society) forgot the real taste of raw aliments and artisanal intermediate products.
Our daughter is allergic to sunflower oil which is commonly used to adulterate the olive oil. Chips supposedly made with olive oil will sometimes give her a rash.
For bottled olive oil we try to buy local California olive oil...,