I’m renaming this summer, “The Summer of Jam.” Before June, I’d never thought to make the fruit spread before. That’s what grocery stores are for, right? Fast-forward two months, and I’ve helped make hundreds of gallons of jam at work. I was surprised by how simple the process was but how versatile and flavorful the outcome is. It was sometime during my fifth batch of jam when I was standing over a kettle of 200°F fruit that I thought, “Why don’t I do this at home?”
Before throwing fruit to pot, we need to understand the science behind jam*. Jamming is essentially a well choreographed dance between pectin, sugar, and water. In order to create that lovely jam texture, you need to create a network of pectin. Unfortunately, pectin is high-maintenence. It’ll only bond with itself, if the conditions are exactly right. It’s like how Barbara Streisand will only give an interview, if there are rose petals floating in water nearby. High-maintenence.
Similar to Babs’ roses, the pectin inside fruit is suspended in water. In this environment, pectin actually repels itself.
We need something that will pull the water away from our finicky pectin. Enter sugar.
In the presence of sugar, water ditches pectin and clings to sugar. Now that pectin is all alone, it’ll start bonding with itself right?? Not quiet. Pectin needs one final nudge in the jam direction. That nudge comes in the form of acid, in our case, lemon juice. The acidity in lemon juice gives pectin the final push it needs to finally bond with itself and thicken our jam.
We’ve given pectin the diva treatment it demanded, and it’s forming the perfect pectin network, but there is still one final problem. The sugar we used to draw water away from the pectin pulled too much water out of the fruit, and now it’s thinning out our jam. How do you get rid of excess water? Heat! Boil out the water on the stove, and you’re left with a delicious homemade jam that’ll trump anything you’d find at the grocery store.
Once you have these basic principles down, you can make countless combinations of jam flavors. On my first go, I kept it simple: strawberry jam with a hefty dose of lemon. It’s seductively sweet yet subtly tart. I schmear it on everything: toast, bagels. I even used it as a layer in a strawberry shortcake recipe. I’m slightly obsessed. At this point, “The Summer of Jam” may very well turn into “The Fall of Jam.”
Happy Schmearing— I mean—Sifting!
*Personal Admission #25: I never liked chemistry in school, but now I’m a big ole pastry nerd. How can you not be?! It’s science you can eat!
- 2 pints fresh strawberries
- 4-5 Tbs. lemon juice, about 2 lemons
- 4 1/2 cups sugar
- Place 5 metal spoons on a plate in the freezer.
- Remove stems and cut the strawberries in half.
- Combine strawberries with sugar, 4 tablespoons lemon juice, and squeezed lemon rinds in a large bowl. Allow the strawberries to release their juices and moisten the sugar, about 10-15 minutes.
- Transfer strawberry mixture into a large pot with tall sides. Cook on medium-high heat, stirring regularly, until sugar dissolves and starts to boil, about 10 minutes.
- Once at a boil, the strawberries with start to produce a large amount of foam. Continue to cook on medium-high, stirring gently. The foam will subside after about 10 minutes. Remove the foam from the surface with a ladle and discard.
- Taste the jam to determine if it needs more lemon juice. I like my jam on the tart side, so I threw in another tablespoon. This
- step, of course, is optional and depends on the quality of your strawberries.
- Allow jam to cook until the boil starts to slow and the edges begin to shine, about 10 more minutes.
- Remove jam from heat. Take a spoon from the freezer and scoop out a small amount of jam. Return the spoon to the freezer for 5 minutes.
- If the jam on the spoon is set after 5 minutes, then your jam is ready. The jam is set when it slowly runs off the spoon when tilted. I look for a pancake syrup consistency. If it's too runny, return to the stove and cook for another 5 minutes, and then test again. Repeat this process until the jam is set. It's important to remove the jam from the stove, when doing the frozen spoon test. It will prevent you from over cooking the strawberries and ending up with a hard jello-like jam.
- Transfer strawberry jam to an opened quart container and allow to cool on the counter before moving it to the fridge/spreading it on everything you eat.