We love avocados here. We buy in bulk to use in omelets, salads, and as a snack. This fantastic delicious and nutritious food provides a creamy texture and healthy fats that are welcome to any meal. Of course this only applies when they've given appropriate time to ripen. An unripe avocado just isn't any fun to deal with.
After buying a bag and setting them on the counter for a few days, they become ripe enough to eat. But something changed for a period of time around the fall and winter months. The avocados sat out in the open for over a week, and then... nothing. Still hard as a rock. What happened? Being based in Minnesota, the speculation was that the cold weather during transport and storage of the avocados was affecting the natural ripening process. It was also possible our local store was receiving produce from a different supplier and there were genetic differences. It's a bit of a mystery.
Avocados aren't cheap, and we were not willing to throw them out. A bit of research suggested putting the avocados in a brown paper bag to stimulate the enzymes needed to ripen the fruit. There were also suggestions of putting a banana among them for similar reasons. It sounded like and odd thing to do, but there wasn't anything to lose, so we tried it out.
The results were great! We successfully ripened every single avocado. With future tests, the banana wasn't necessary, but it seemed to make the process more efficient. To this day, the paper bag trick has not failed. It's now routine here to buy avocados just before the weekend, throw them in a paper bag, and wait 3 to 5 days for them to become perfectly ripe and ready to eat.
While this experience is largely anecdotal, there does seem to be some solid science backing this up. If you're as much of a fan of avocados as we are, give this a shot. You'll be surprised.