No matter what time of the tomato season it is, gardeners always have green tomatoes. With that in mind, this tomato preservation procedure can be used as long as you have fresh-from-the-vine, green tomatoes. Do not use tomatoes that have endured even one night of frost. It’s too late for them… and for you, my culinary friend.
I discovered this recipe at allrecipes.com, more than a decade ago. It was before I became an advanced Master Gardener and advanced Master Food Safety Advisor with the University of Idaho. So, I made the jam and processed (canned) the product in a boiling water bath. It was delicious. Even my then-tomato-hating daughter never knew what REALLY went into Mama’s Raspberry Jam. Fast forward to what I now know, and I currently prepare this recipe and freeze* the jam.
Start with any type of green tomato. I like to use my San Marzano variety. It’s a prolific and popular type of paste tomato with a higher flesh-to-juice ratio. Wash your tomatoes; remove any stems or blemishes and quarter.
Place them in a food processor. Using pulses, process them until the tomatoes have become “nubby,” (like the drupelets of a raspberry). If there is residual juice, rinse the nubs under water, using a mesh strainer. Process the green tomatoes until you have four cups.
Place the nubs into a pot. Turn the burner to medium-high and add 4-cups of sugar and 6 oz. box of raspberry gelatin. Bring the mixture to a rolling boil and then reduce the heat and simmer for 20 minutes.
Let the mixture cool a bit before ladling it into freezer-safe containers, leaving ½ inch of headspace between the jam and the lid (for possible freezing expansion).
Remember to label and date the containers before you put them into the freezer. The added bonus of freezing this jam is that it allows you to adjust the amount of sugar you put into the recipe. Test it. If four cups is too much, adjust it. Try to use the jam within six months.
Be certain to keep a container in your fridge. Once you taste it, you’ll wonder why you haven’t been using your green tomatoes… all along.
*As an MFSA, I can recommend only laboratory tested and approved recipes. I’ve yet to find a university or national food organization that has tested this recipe for water bath canning. It’s a GREAT recipe though. It sets up so nicely and keeps well in the freezer.
You can also hear Gretchen talk about her raspberry green tomato jam on the D&B Show podcast by clicking here or listen below.