http://archive.boston.com/business/...ands_fared_in_olive_oil_study_by_researchers/ So yes, some of the olive oil sold in Walmart was not fake -- at least in 2010.
When buying olive oil, look for the olive branch symbol shown in the link below. This is the logo of the North American Olive Oil Association and indicates the producers that have agreed to have their oils tested. This is mainly a concern for imported oils. Read the FAQs below the list in the link for more detailed info. https://www.aboutoliveoil.org/certified-olive-oil-list California Olive Ranch has a product that is 100% California olives. Just make sure you check the label and don't get the Destination/Global bottle. Walmart carries it. Colavita is also a good brand. You should be alright with any imported brand that has the NAOOA red circle olive branch symbol on it. Usually it is on the front of the bottle, but sometimes it is on the back label. Always make sure you get Extra Virgin that is First Cold Pressed. It should say this on the label. If it only says Cold Pressed you are not getting what you want. Also avoid oils that just say olive oil or has pure or light on the label. Organic is more expensive obviously, but make sure it is Extra Virgin. Better olive oils cost more. Here is a link to the American Olive Oil Producers Association. In the U.S., olive oil is produced in California, Arizona, Texas, Georgia, Florida, Oregon and Hawaii. You should not have to be concerned about quality testing on any of these olive oils. http://aoopa.org/olive-oil-101
OliveOilsLand https://www.oliveoilsland.com/bag-in-box/ Extra Virgin Olive Oils https://oliveoillovers.com/bag-in-box/ Olive Oil Heat, Light and Oxygen - Search https://duckduckgo.com/?q=Olive+Oil+Heat,+Light+and+Oxygen First cold press Olive Oil Heat, Light and Oxygen - Search https://duckduckgo.com/?q=First+cold+press+Olive+Oil+Heat,+Light+and+Oxygen Benefits of Cold Pressed Olive Oil https://www.newhealthadvisor.org/Cold-Pressed-Olive-Oil.html A three-year study confirms that oxygen, light and heat are indeed among extra virgin olive oil’s worst enemies. The bottom line in “The Effect of Storage Conditions on Extra Virgin Olive Oil Quality (PDF)” is that olive oil should be stored at cool temperatures, away from light and without exposure to oxygen. Therefore Olive Oil in Bag-in-Box - Search https://duckduckgo.com/?q=Olive+Oil+in+Bag-in-Box