I lost count of how many times I went blackberry picking in August.
Enough times that I started to run out of room in the freezer for all the berries I was picking. I knew that I was going to make jam, but I didn’t want to do it on the same day as picking. Last year I made jam on a rainy day in September, using berries that had been recently picked and frozen, but I remembered that thawing and de-seeding the berries had been a bit of a hassle.
So this year I de-seeded half the berries before freezing, and measured the pulp into freezer bags, so it would be ready to go whenever I got around to making jam. I’m also dealing with a repetitive stress injury on my left wrist (from knitting), so this helped reduce the amount of work I was doing with my wrists on any one day. I prepped berries on two different days, and for one batch I de-seeded them using a colander and for the other I squeezed the pulp through cheesecloth. The latter method is messier but quicker and seemed to be easier on my wrists, and is probably the method I’ll use in the future.
This past weekend was nice and cool, and I had already gotten used to canning with my batch of chutney, so I made two batches of jam on Sunday. Thawing the bags of blackberry pulp was easy, but pouring all the pulp out of the bags into the pot was not as easy. So I’m not totally enthusiastic about this method; maybe I should freeze the pulp in yogurt containers or something similar that would be easy to scrape out?
This year was the first time in quite a long while that I’ve used added pectin in the jam recipe; other years it’s just been blackberry pulp + sugar. When I go through the USDA’s canning guide (all sections linked here), I become leery of modifying the fruit to sugar ratio, but at the same time I’m not thrilled with how much sugar is required. So this year I got the type of pectin for reduced sugar recipes. But even with that, I thought the amount of sugar called for was excessive: 4 cups of sugar for 5 cups of berry pulp.
So I reduced the sugar a bit from that; 3.5 cups sugar and a bit more than 5 cups of crushed berries. And then that made me feel anxious about whether the jam would set, so I cooked the first batch longer than the needed 1 minute after it reached a roiling boil. I haven’t opened any of the canned jars yet, but I suspect the first batch will be too stiff. I stuck to the prescribed cooking time on the second batch.
Doing two batches back to back wasn’t too difficult. The time consuming part was sterilizing the jars, which was probably an unnecessary step since they were being processed for 10 minutes in the water bath canner. But that gave me time to get dishes done in between! End result: 13 half-pint jars of jam.