Several years ago for my job I had occasion to visit a vegetable processing facility. This was a warehouse type building with miles of conveyor belts and industrial sized vegetable sorting, cleaning, cutting, and packaging machines. Incoming produce included bananas; tomatoes; and lettuce, cabbage, and carrots for making those bags of pre-mixed salad you see in the grocery store.
What really caught my attention, though, were the thousands of crates of tomatoes stacked two stories tall and packed into a little room. The tomatoes were bright green, and rock hard.
(Hmmm… how far from ripe must they have been picked? What nutrients were they lacking by missing out on all that photosynthesis and natural vine ripening? Oh, but who cares about that!)
A door came down and the little room was sealed shut, and the tomatoes were gassed. (Same idea as when you put produce in a paper bag to ripen faster – just done synthetically on a massive scale.) Several hours later the door opened, and the tomatoes were bright red – gorgeous and ready for the grocery store shelves!
So now you know why store bought tomatoes are so awful.