Blackberry JamMakes about 8 half pint jars
2 quarts Blackberries rinsed
Sugar between 1 1/2 and 3 pounds depending on your liking
Pectin 2 packages or 3-4 tablespoons of bulk
Canning jars or freezer canning jars or leftover whipped cream cheese containers if you got 'em.
Making jam should be fun. NOT stressful, Not bothersome. Fun! If it's not fun for you, you should not make jam. Really.
That being said I am going to tell you how to easy can and seal your jam. A magic trick really. I don't sanitize my jars in boiling water and I don't use a hot water bath because that is too much trouble for me. However, I don't really have freezer/fridge room for freezer jam so shelf stable is important to me. If shelf stable is not important to you, or you just really like insane amounts of boiling water, by all means use whatever method works best for you.
You will need:
Glass canning jars with their rings and unused lids. (Used lids will not reseal) or whatever you want to put the jam in.
Canning funnel. If using metal you can sanitize it with the jars.
Metal or ceramic bowl to soak the lids in.
Large wide pot to boil the jam in.
Blender, food processor or a food mill. ( I prefer the blender)
Mesh strainer if not using a food mill.
Clean, lint free towels.
A Jam recipe you like. I like my blackberry.
When you are preserving something you want to keep shelf stable the very most important thing is clean. Clean utensils, clean work surface, clean hands, clean, clean clean.
First off turn your oven to 250. Line a cookie sheet with a clean lint free towel. Thoroughly wash your canning jars and rings in hot soapy water place the rings, ladle, tongs. (metal funnel) and jars right side up on the towel lined cookie sheet and place in the oven for at least one hour. This is a replacement for a boiling water bath to sanitize the jars. Do not skip or skimp on this step.
I want to note if you have a dishwasher with a sanitize cycle you can use it for the initial wash but you still want to put the jars in the oven at 250 while preparing the jam.
Take a amount to weigh the bowl you are using. It will come in handy when figuring out sugar ratios later.
Mix the pectin with 1/4 cup sugar and set aside.
Crush your blackberries in a blender or food processor (May take two to three batches.) Pour the puree into a metal strainer set over a bowl to catch the puree. Work the puree through the strainer by stirring and mashing until only the seeds and residual pulp are left in the strainer. Discard seeds and pulp. Weigh the puree (subtracting the bowl weight) Start with the puree weight (Mine was 3 lbs 6 oz) and divide it in half to get the initial amount of sugar to add. (In my case 1 lb 11 oz) Stir this into the puree and give it a taste. If it's sweet enough proceed to the cooking stage. If not. Add more sugar two ounces at a time until it is sweetened to your taste.
Place the canning lids (plastic funnel) in a bowl and cover with very hot water.
Pour the puree into a large, heavy bottomed saucepan and bring to a boil over high heat. Watch it. Don't leave. If you have to leave turn it off. It burns quick, It burns hot. It burns high. No one wants that. So yeah, don't leave, turn it off if you have to. Stir it too.
Once it comes to a boil stir in the reserved sugar/pectin mix. Bring it back to a boil and boil hard for one minute. Turn off the heat.
Now here's the semi tricky part. After the jam has boiled for one minute you need to test it for "set" which is how thick your jam is. Pick up some of the hot jam (maybe a half teaspoon) on a metal spoon and put the spoon in the freezer. Wait a minute then test it. if it seems jammy enough you can start canning. More like ice cream topping? Needs another tablespoon or two of pectin and another minute at full high boil.
Once the jam is the way you like it.Take the jars and rings out of the oven. (Leave them on the cookie sheet) Turn off the jam. Place the canning funnel in the first jar you want to fill. Use a ladle to fill the jar to within 1/4 inch of the top. Do not overfill or the magic trick won't work. Remove the funnel, put it in the next jar, lather rinse repeat until you run out of jam or jars or both.
This is the magic trick (and as far as I know it ONLY works safely with jams and jellies.) The heat from the jam against the lid melts the sealing compound forming a tight seal while the cooling jam creates a vacuum. Once cooled flip them over and test the bouncer to be sure they are tightly sealed. I've never had one not seal but if you do, put the jam in the fridge. It'll be fine in there for six or so months. (Because it'll last six or so months ha ha)
Loosen or even remove the rings from the jars. Properly sealed lids don't need the rings to stay put. Tightened rings will also hide if something went wrong on a bacterial level. Bad stuff gives off gas which will pop the lids off giving you a good warning "Don't eat me!" So loose or no rings discard if lids pop on their own.
Now go enjoy your jam.
In your jammies...