Strawberry jam

After reading a few similar techniques on the Chowhound discussion boards, I pretty much used this one (also referenced below).

Ingredients

• 1 flat of strawberries, washed, hulled, and quartered (this ended up being about 5 lb)
• 5 cups granulate pure cane sugar
• Juice of two lemons (this ended up being about a 1/2 cup, if I recall correctly)

Directions

1. Put strawberries in large non-reactive bowl (I used an enamel-lined steel bowl usually reserved for making timpano) and pour sugar over them. Fold together. Refrigerate overnight to let macerate. Stir every once in a while to help dissolve the sugar sludge that might still be on the bottom of the bowl.

2. The next day, the berries will be floating in a gorgeous pool of strawberry syrup.

3. Transfer fruit, syrup and all, to a large non-reactive pot (stainless steel, Pyrex, or enamel-lined) and bring to a boil.

4. Let boil for 3 minutes.

5. Remove from heat and let stand for at least a few hours. (You can also refrigerate this mixture overnight.)

6. Strain the berries into a colander and set aside.

7. Bring the syrup to a boil again. Keep boiling until it gets to 220 degrees (the jelly stage, apparently?).

8. Meanwhile, if you don't like your jam too chunky, pulse the berries in a food processor a few times to break them down into smaller pieces.

9. Once the syrup has reached 220 degrees, add the berries, and let boil for 3 to 4 minutes. (I ended up bringing the jam -- once the berries had been added -- back up to 220 degrees because after 3 to 4 minutes, the jam was still very liquidy. This took about 25 minutes, I think.)

10. Process the jam in jars (canning technique can be found in the recipe for kumquat marmalade).

Notes & References

• A couple of Chowhound threads I read on making strawberry jam without pectin (including this one referenced a cookbook by Helen Witty called Good Stuff. The book appears to be out of print, but it might be worth checking out at a used bookstore. Her technique is evidently to let the berries macerate in sugar to create the syrup. It is then just the syrup that is cooked to a jam, with the actual fruit chunks getting cooked only minimally to preserve their fresh flavor. My jam still tasted pretty cooked to me, but this is probably because I didn't cook the fruit for as short a time as was directed in the recipe I used.
• Here's a Bay Area Bites blog post (KQED) that discusses the same Witty method but advocates less sugar, which is right, I think. The sugar definitely could have been cut in half.* It took a long time to get to 220 degrees. I didn't want to do this over high heat for fear of scorching the jam. So I kept it at medium. I might raise the heat next time to medium-high and do more stirring.
• Many fruits contain a lot of pectin already and make the addition of commercial gelling agents unnecessary for jam. Berries are a low-pectin fruit, though, so the addition of lemon juice, which evidently is high in pectin, helps with the setting of a berry jam. Lemon juice also brings the added benefit of brightening the berry flavor and adds a tasty bit of tartness. Next time, I'd use even a little more, I think. Perhaps 3/4 cup?
• 2011-08-01: I used 2.5 cups sugar & 1/2 cup lemon juice for 4.5 lb strawberries, and this was plenty sweet. Additionally, using high heat did scorch the jam in a few spots on the pan but did bring it up to 220 degrees much more quickly. Finally, after heating the jam to the jelly stage and adding the fruit, I cooked it for the recommended 3-4 minutes without letting the jam go up to 220 degrees again.