The first thing with EVOO is to make sure it's not fake. Fake EVOO has things like canola oil and other types of oil mixed in, which means it's actually detrimental to your health.
If you want to test the EVOO put a shot glass of EVOO in the fridge overnight. Genuine EVOO will 100% solidify. Should there be any liquid residue on the surface it's fake EVOO.
Secondly, ONLY ever buy EVOO that is in a dark (preferably green) coloured bottle. That is what keeps the light out and therefore prevents the oil from going rancid.
Thirdly check the labels, front and back to ensure that the oil is cold pressed and that there is a produced date AND a best before date on the rear label. The maximum period between the produced date and best before date MUST be 18 months.
Bertolli is genuine BUT their rear label only has a best before date, so there is no way of knowing when it was produced and it could have been anywhere up to 2 years or more prior to the best before date.
Carbonell is also a genuine EVOO and it has both dates on it's rear label. This is the one I currently use.
Monini is another genuine oil but my local supermarket only sells it with an unhealthy oil as a freebie stuck to it, so I haven't been able to see any dates on the rear label.
Never buy EVOO in plastic or clear bottles, it will go rancid very quickly.
I buy my oil at Lotus's. My local Makro has Bertolli but only in 1 litre bottles. Based on information I've seen in videos by olive oil experts and reading data, it is recommended by those experts that for home use you should only purchase 250 or 500 ml bottles. 1 litre bottles and larger quantities, especially in tins/cans are meant for restaurants that have a heavy turnover in EVOO use.
Should you, or anyone else, have any genuine questions please feel free to message me rather than post an enquiry as a comment.