Simply put, green tomatoes are red tomatoes. There is no difference, they’re just unripe. Often times, you’ll find green tomatoes at farmer’s markets because they are eager to get their produce out there for sale, and they’ll pick them off the vines well before they’ve turned into the traditional red ones you see at a grocery store. By the time any commercially grown tomato reaches the grocery store, it’s usually already red, although there are genetic modifiers that can keep them green or just quick ways to get to market. Also, once off the vine, tomatoes don’t ripen the same way.
If you do buy a green tomato and you want to keep it that way, you’ll have to find a way to hinder the ripening process. For one, a lot of people have fruit and vegetable bowls they keep in their kitchen. These are often on kitchen tables, near large windows. This is a big no, no for green tomatoes, because being exposed to the sun is going to help them ripen. You basically want to do exactly what a tomato plant wouldn’t want, cold temperature and little light. That’s why the crisper in your refrigerator is the perfect place. Those tomatoes are going to ripen eventually, but if you keep them in the cool crisper minus the light, they’ll stay green a lot longer. How long is anyone’s guess? It just depends on when they were harvested and also the variety of tomato. No tomato will stay green forever.
You may ask, what really differs in the green tomatoes other than their color? Is there a difference in taste? A lot of people find that the unripe green tomatoes have a much tarter taste to them. Their composition chemically and this nutritionally is almost identical. The tarter taste is attributed to the fact that a little less sugar has seeped into the plant as it ripens on the vine longer. That’s where you’ll see a difference between red tomatoes ripened on a vine and green tomatoes that you bring home and ripen by putting them near the sun, under your window sill.
So, there is a difference between green tomatoes and red ones, a slight one. But hardly an impact chemically or nutritionally. They make for a lot of great recipes though with their added tart taste. A lot of people like to make green tomato pie, which they say tastes like a tart apple one. Of course, there’s the traditional fried green tomatoes, especially if you’re into Hollywood! Basically though, you can use green tomatoes any way that you could use a red one. The difference is so minimal you won’t even notice. You will notice a different in aesthetic though, and a lot of people have fun making green salsas or traditional dishes like caprese salad with their green counterparts. Enjoy!