Ripe tomatoes should be completely red or reddish-orange, depending on the variety. They will have a sweet, subtle aroma and will give slightly to gentle palm pressure. When you pick our tomatoes whether from the farmers market or the grocery store, select tomatoes at various degrees of ripeness and keep them at room temperature. Use the ripest fruit first, just as you do with bananas and avocados. Never refrigerate a tomato that is not fully ripe.
Cold temperatures destroy flavor and stop the ripening process.
Once fully ripe, a tomato can be refrigerated, but only for a couple of days. When they are left for a longer time the texture and flavor begin to deteriorate. To hasten ripening, place fresh tomatoes in a brown paper bag or in a fruit-ripening bowl. As the fruit ripens, it emits a natural gas-ethylene. This gas speeds up the ripening process when confined around the fruit on a closed bag or fruit-ripening bowl.