The thread about trusting others to go to the grocery store for you got me thinking. When I have had to (health issues) ask people to shop for me produce has been the most difficult item to deal with. While I know what a "nice" tomato is I've learned most don't! :-)
The point really hit home at Thanksgiving. My sister had requested my help. We were shopping several days ahead and she grabbed a package of mushrooms. They were presliced and already looking over the hill. I told her there was no way these would last and that I would look for them elsewhere. She looked at me quizzically. I asked if she was interested in why, she said yes and we had a mini mushroom lesson. It was funny - several shoppers listened in - even the produce girl!
I do have more interest in food than my sister. I guess I largely taught myself how to choose produce. I observe, make mental comparisons, read and ask questions. But a certain amount just seems to be innate. Ripe plantains seem to be one of the few counter-intuitive items I buy.
How did you learn?