Taste is actually a very complicated subject. Taste is a complex sensation of flavours, smells, consistency and memories perceived in the mouth.
Taste is something that is learned over time. Smell is actually a much stronger component to how something tastes than the actual taste of a food in your mouth.
In a study by Duke University on the Taste of food: 10% of what you taste comes from the mouth and how actually it tastes, 40% is the smell, 30% is the consistency and 20% is it's appearance. Your tastes have been influenced by your age, your gender, your friends, your cultural backgrounds as well as your social values.
You really do eat with your nose, your mouth and your eyes. Just think back to the last time you had a cold, remember how you couldn't taste anything because you had a plugged nose. Just to prove this point plug your nose and taste something like an orange or a tablespoon of olive oil. Chances are you will taste sweet, salty, bitterness but not much more, then taste the same thing again breathing in as you enjoy that slice of orange and you will taste all the aromas and complexities of that oil.
"Tell me what you eat and I will tell you who you are!"........Anthelme Brillat Savarin (French gourmet and lawyer)
If you have only tried Extra Virgin Olive Oil from the grocery store shelf, in a bottle that usually costs $4.99 - around $8.99 a bottle then you have never really tasted Extra Virgin Olive Oil.
I am not implying that that bottle you bought from the grocery store is fake (but you would be amazed at how much of it actually is!) I am not here to bash the big brands (someone else can fight that cause) however, I would challenge you to go to a reputable seller of Extra Virgin Olive Oils (like me.) and work with them to choose a nice bottle. When you get this nice bottle home take out 2 little shot glasses and pour a tbsp of each oil in these glasses (oh don't freak out, it's just a tbsp) Cover the good extra virgin oil with your palm and cup the glass to warm the oil with the heat of your hands slightly. Do this for 15-20 seconds then remove your hand and stick your nose right in the glass and smell the oil. It should smell green like grass or fresh artichokes or even more fruity like a ripe olive. Don't really worry about describing it as long as it smells like something in nature...fruit, grass, almonds as long as it doesn't smell bad or something that is un-natural like say metal (that is bad in any oil!)
Now take a mouthful (don't just dip your tongue- it's just a tbsp put it in your mouth and swirl it around, then swallow it. Then as soon as you swallow it smile as wide a smile as you can and open your lips with your teeth closed. Still smiling suck in some air 2-3 times like you are taking a couple of breaths through your teeth. Don't be delicate about it, suck in the air, hard a few times. What do you taste? is it strong, is it a bit peppery, did it make you cough! (that tells you its good , don't be afraid of the cough)Now do the same thing with the stuff you bought for $6.99 at the grocery store......chances are that one will have very little flavor or peppery taste or pungency to make you cough. That is because the big brands typically have stripped away all the flavor and ultimately the beauty of olive oil.
At the very least this test will prove to you that YOU can taste differences in Olive oils!
Most people think why should I invest in a good bottle of olive oil for $30 when I couldn't taste the difference?
I would say most people can't taste the differences between oils bought from the big brands in the grocery stores because most of those oils don't have much flavor but, if you try the best extra virgin olive oils the world produces I know you will be able to taste differences and find ones you prefer over others.
Remember Olive oil is similar to wine in that the same oil can have differences year over year. Some years are sunnier, or rainier or something in the environment can affect the harvest although the variety of the cultivar or blends can be the same. Some years the oil is more pungent or more fruity because it is a real product and not something that has been stripped of it's essence to make it the same product consistently for all time.