How to Prepare Your Tomatoes for Canning
This recipe works for any amount of tomatoes. I've canned as few as 10 lbs, and as many as 60 lbs. As you read through this recipe, you'll see why I don't indicate how many tomatoes to use.
HOW TO REMOVE THE SKINS:
Put a big pot of water on the stove to boil.
Meanwhile, wash your tomatoes in cold water.
Once the water is boiling, drop in your tomatoes a few at a time.
The tomato skins will begin to blister (peel) after about one minute. Have a fork handy, because this is the easiest way to remove them from the boiling water.
If the tomato skin is still difficult to remove, then put it back in the boiling water for another 30 seconds or so.
Using a knife, remove the skins (they'll peel right off) and then remove the stem end. As I peel and de-stem them, I drop them into my largest pot.
How To Can Tomatoes
While the pot of peeled tomatoes is coming to a boil, I prepare my jars and lids. I always put my jars in the dishwasher about the time I start peeling tomatoes. My dishwasher will have the jars clean and piping hot by the time I'm ready for them.
I put a skillet on the stove with about one inch of water in it, and put my lids in so they can boil -- the lids need to be sterilized, and the heat will soften the rubber seal.
How long should your tomatoes boil? Long enough for the tomatoes to begin to break down, and the entire pot of them is boiling rapidly. Note: there will be juice in the bottom of the pot when you first put it on the stove, and that liquid will come to a boil rather quickly. Wait a while though -- make sure the tomatoes themselves have heated to the boiling point. See the photo below.
How long will this take? It depends on how many tomatoes you're canning. Sometimes this takes 15 minutes, sometimes half an hour or 35 minutes if I'm using my largest pot and it's full.
Once the tomatoes are boiling, I add salt -- approximately 1/2 tsp. per quart. I just guesstimate since the acid of the tomatoes is plenty and they don't need salt to preserve them. You can always add salt later when you open the jars to use them.
I put a funnel into my hot clean jars and ladle the tomatoes into them. Leave about a 1/2 inch headspace. See the photo below.
Wipe any tomato juice off the tops of the jars, then put your lid on, then screw on your rings tightly. I turn the jars over, then move on to the next one.
Set your timer for about 12 minutes -- that's how long I keep my jars upturned before I turn them right side up. Then leave them on the counter for about 12 hours to fully come to room temperature. As they cool, you'll hear the lids popping downward -- indicating a complete seal.