The Absolute Best Way to Make Jam, According to So Many Tests

In Absolute Best Tests, our writer Ella Quittner destroys the sanctity of her home kitchen in the name of the truth. She's mashed dozens of potatoes, seared more porterhouse steaks than she cares to recall, and tasted enough types of bacon to concern a cardiologist. Today, she tackles jam.

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Jam is perhaps summer’s greatest spoil, if you, like me, don’t love a pool party and get a stomachache from Mr. Frosty.

Put in a way that doesn’t center my lactose intolerance, “The luxury of the best fruit, still pulsing with life, warm from the field, is in my mind the same sort of miracle as a baby being born.” That’s how April McGreger, who is both an award-winning maker of preserves and a person who speaks about jam in a way that makes me blush, described it when I reached out to discuss my latest Absolute Best Test trials.

McGreger, whose book The Complete Guide to Canning & Preserving comes out in spring 2022, told me that during the summer months, she often imagines herself “buried under a mountain of strawberries, which I claw my way out of, ending with perfect order sparkling on the shelf.”

Her preferred method for strawberry jam is to first macerate in sugar, which she says should be added in a weight proportionate to 60 to 65 percent of the weight of the berries, because of their high water content and fragility. Then, she cooks the mixture in as small a batch as possible on the stove. (She likes the wider surface area of a skillet for quicker evaporation, but notes that if you are using a large saucepan or stockpot, it’s best to cook no more than 3 pounds of berries at a time, for optimal flavor and color.)

And while she never did comment on whether or not pool parties are awkward, her advice to me was indispensable as I set forth on my noble mission to test six methods of making jam:

1. Err on the side of undercooking. (“Overcooked jam is trash,” she said. “And undercooked just means you spoon it instead of spread it.”)
2. Add plenty of lemon juice to preserve color and brighten flavor.
3. Stay away from super-ripe strawberries.

Speaking of which…

Yes, in news that may shock and disturb you, the best strawberries for jam-making are not ripe ones.

“Since strawberries are already low in pectin, they need to be firm, a quarter of them even slightly underripe. I throw in a small portion with green tips for a pectin boost,” said McGreger. “Those perfectly ripe, juicy berries from the farmers market that are perfect for eating by the handful are usually too ripe for making into jam.”

Accordingly, for each jam trial, I used berries that presented some resistance when poked and were a few shades less vibrant than their riper counterparts. For each batch:

• 1 heaping cup (165 grams) hulled, quartered strawberries
• ½ cup (99 grams) granulated sugar
• 1 tablespoon freshly squeezed lemon juice
• 1 big pinch Diamond Crystal kosher salt

The exceptions to this were in the no-cook chia trial, for which I used maple instead of sugar, and in the no-cook freezer trial, for which I added pectin as called for in the recipe. Any of the recipes below can be scaled by simply doubling or tripling them.

A Note on Preservation

McGreger told me that historically, many jams were made with an equal weight of fruit and sugar, since sugar lowers water activity, and that much sugar renders vacuum-sealing and canning unnecessary.

But for a less cloying flavor, McGreger said you can use 60-ish percent sugar by weight and still keep jam for 2 to 4 weeks in the fridge after opening, if you store it in smaller jars and wait to crack each one until you’re ready to use the jam.

“Mold is generally what causes small, moderately sweetened batches of jams to spoil, and mold needs oxygen to grow,” she said. “If you put it in one larger jar that you are constantly opening, exposing it to contamination through human hands and air, for the whole second half of its life in the fridge, the percentage of empty space and air at the top of the jar just gets larger and larger.”

She recommends canning when your jam objective is to preserve the local harvest for future months.

Stovetop Only

Adapted from Food52.

1. In a heavy saucepan, combine 1 heaping cup of quartered, hulled strawberries with ½ cup of granulated sugar, 1 tablespoon freshly squeezed lemon juice, and a big pinch of kosher salt.
2. Set the pan over low heat and cook—stirring every minute or so and smashing the berries with a wooden spoon—until the mixture begins to bubble, and the sugar granules are no longer visible, 4 to 5 minutes. Taste: Too tart? Add a little more sugar. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt.
3. Continue to simmer over low heat for about 30 minutes, stirring occasionally, until when you dip a frozen spoon into the mixture, let the jam cool on the spoon, then run your finger through the cooled jam, it leaves a clear trail.
4. Turn off the heat, let cool, and transfer to a jar. Refrigerate for up to 1 month.

I am an openly lazy cook, so I was most excited about this method, which requires little more than 5 minutes of chopping and the sort of spoon–helicopter parenting (Jamrenting? Kill me in my sleep) that calms me anyway.

The resulting jam was excellent—somehow a bit sweeter than the sheet pan batch, despite the same ingredient proportions, with a flavor more like IHOP strawberry syrup, in the best possible way. A spoonful of it was like eating the tail-end of June whole.

The smashed berry pieces dissolved toward the end of cooking to produce a smooth texture that set up into a thick, spreadable jam in the refrigerator.

Macerate + Stovetop

Adapted from Food52.

1. In a heavy saucepan, combine 1 heaping cup of quartered, hulled strawberries with ½ cup of granulated sugar. Let macerate for about 30 minutes, or up to 3 hours.
2. Set saucepan over medium heat and bring to a boil, stirring every 30 seconds or so and smashing the berries with a wooden spoon. Continue to cook, scraping the bottom as you stir, for another 15 to 20 minutes, until the mixture is jammy and thick.
3. Add 1 tablespoon freshly squeezed lemon juice and a big pinch of kosher salt and reduce the heat to medium-low, then cook for another 10 minutes, stirring often. Taste: Too tart? Add a little more sugar. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt.
4. Cook over medium-low heat for another minute or so, until when you dip a frozen spoon into the mixture, let the jam cool on the spoon, then run your finger through the cooled jam, it leaves a clear trail.
5. Turn off the heat, let cool, and transfer to a jar. Refrigerate for up to 1 month.

There were two main differences between the outcome of this batch and the stovetop-only batch.

The first was flavor. The macerated + stovetop jam was somehow fuller: The sugars tasted more caramelized, and the strawberry juice more concentrated. It was also slightly less sweet than the stovetop-only jam.

The second was texture. I conducted the same amount of spoon-mashing between both batches, but the macerated + stovetop jam ended up a bit chunkier than the stovetop only jam. (This would have been easily rectified if I had taken a fork to it.)

Since the added time with this method was completely hands-off, unless I were in a rush, I don’t see why I wouldn’t macerate to get the flavor boost in the future.

No-Cook Chia

Adapted from Food52.

1. In a medium bowl, use a fork or potato masher to smash 1 heaping cup of hulled, diced strawberries. Add 4 teaspoons of chia seeds, 1 heaping tablespoon of maple syrup or agave syrup, 2 teaspoons freshly squeezed lemon juice, and a big pinch of kosher salt. Stir.
2. Cover with plastic wrap, foil wrap, or a cloth, and refrigerate for at least 2 hours or until thick. Taste: Too tart? Add a little more maple or agave. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt. When you’re satisfied, transfer to a jar. Refrigerate for up to 1 week.

No-cook chia jam is truly no-cook—you can and should make this in your bedroom, bathroom, or on an airplane flying high over the sea as you ferret away many jewels after an outlandish and cinematic heist. It requires no heat source, stirring, or skills. It does, however, take a while to set in the refrigerator, so if you’re in a rush to fucking guzzle a truckload of jam ASAP, you might be better off with another method.

That said, the chia jam was extremely pleasant, with a lighter flavor than any other batch. Perhaps because it was never heated, the lemon juice shone through much more brightly, for a jam that reminded me of a SweeTart on a sunny day. The addition of maple and lack of granulated sugar (since there was never any opportunity to dissolve) also allowed the strawberry flavor to take center stage.

It would be excellent in a parfait with vanilla yogurt, or spooned over a flourless chocolate cake to cut the sweetness and complement the blunt edges of cocoa.

No-Cook Freezer

Adapted from Pioneer Woman.

1. In a large bowl, use a fork or potato masher to crush 1 heaping cup of quartered, hulled strawberries. Add ½ cup of granulated sugar, 1 tablespoon freshly squeezed lemon juice, and a big pinch of kosher salt. Let sit for 10 minutes, stirring midway through.
2. Taste: Too tart? Add a little more sugar. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt.
3. In a small saucepan, combine 6 tablespoons of room-temperature water and 1 ounce of fruit pectin (I used Sure-Jell). Bring to a boil over high heat while stirring. Let boil for 1 minute, then remove from heat. Pour over the berry-sugar mixture. Stir until sugar granules are no longer visible.
4. Transfer to a jar, cover with a lid, and let sit at room temperature for 24 hours.
5. Use immediately, or store in the freezer for up to 2 months and thaw in the fridge before using.

Freezer jam is something of a misnomer, because you only put it in the freezer if, unlike me, you don’t immediately eat the entire batch with a spoon.

It would be more accurate to call it “countertop jam,” which is maybe less sexy, although, I would rather have sex on a countertop than in a freezer. Anyway, you make freezer jam by mashing strawberries with sugar, lemon juice, and salt, and then letting the mixture sit while you dissolve some pectin and bring it to a boil. You stir the liquid pectin over the berries and cover the fruit, and let it all sit at room temperature until it has set into jam.

This method produced a batch with a bright, brilliant hue. Because the berries were never cooked, the flavor was pert and raw, reminiscent of strawberry shortcake. The texture wasn’t my favorite of the bunch—more gelatinous than loose—but after a jaunt in the refrigerator (for the jam, not me, haha, is anyone still reading this), I hardly noticed, and it spread on toast like a dream. Because the berries remain uncooked, freezer jam is a great opportunity to showcase the delightful flavors of an in-season strawb.

Sheet Pan

Adapted from Food52.

1. Heat the oven to 375°F.
2. On a sheet pan, toss together 2 heaping cups of hulled, diced strawberries, 1 cup of granulated sugar, 2 tablespoons of freshly squeezed lemon juice, and a big pinch of kosher salt. Let macerate while the oven heats.
3. Transfer the sheet pan to the oven and roast about 15 to 20 minutes, stirring midway through, until the strawberries are easily mashed with a fork, and the accumulated juices around the edges of the pan have thickened and begun to darken.
4. Remove the sheet pan from the oven, and mash the strawberries with a fork or potato masher. Once smooth, taste: Too tart? Add a little more sugar. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt.
5. Let cool, then transfer to a jar. Refrigerate for up to 1 month.

“Sheet pan jam” is incredibly fun to say, so this trial got off to a great start. Things did plateau when some of the macerated strawberry–sugar liquid began to caramelize too quickly around the edges, but got back on track when I used a silicone spatula to drag the juices from the corners of the sheet pan into the center of Berry City.

The flavor of sheet pan jam was like nothing I’ve tasted: roasted and vegetal, and distantly pumpkin-y (!). It was much more holiday pie than it was field trip PB&J, and it would have been excellent with some fresh basil.

Of all of the trials, the sheet pan method produced the most rustic, loose jam, which made it perfect for spooning over whipped cream and biscuits, though I imagine it would have spurted right out of a sandwich.

Instant Pot

Adapted from Food52.

1. Combine 2 heaping cups of diced, hulled strawberries, 1 cup granulated sugar, 5 teaspoons of freshly squeezed lemon juice, and ½ teaspoon kosher salt in an Instant Pot.
2. Select SAUTÉ and adjust to NORMAL. Bring mixture to a boil for about 8 minutes, stirring frequently. Press CANCEL.
3. Then, secure the lid on the pot and make sure the pressure-release valve is closed. Select MANUAL and cook at high pressure for 8 minutes.
4. Use natural release to release the pressure. Remove the lid and use a large fork or potato masher to mash berries until smooth. Once smooth, taste: Too tart? Add a little more sugar. Not quite pert enough? Add a little more lemon juice. Too sweet? Another pinch of salt.
5. Select SAUTÉ again and boil for another 5 to 7 minutes, until when you dip a frozen spoon into the mixture, let the jam cool on the spoon, then run your finger through the cooled jam, it leaves a clear trail. Press CANCEL.
6. Let cool, then transfer to a jar. Refrigerate for up to 1 month.

Here’s something that may seem obvious: If you set your Instant Pot to vent immediately after using it to make strawberry jam, it absolutely will spray little bits of sticky goo all over everything you’ve ever owned, including your great-grandma’s antique copper pepper grinder that you had to prize from your father’s grip with promises to keep it safe, always and always.

Other than that, Instant Pot jam was pretty straightforward to make. For reasons that eluded me, the hue of the jam was materially darker than any other batch, and for reasons that did not elude me (pressure cooking), the resulting spread retained quite a bit of liquid.

After giving it another sauté to evaporate the extra juices, its flavor was deep and plummy, and it became quick thick, like Smuckers. I would use this method again if I was craving a more wintery flavor, and I wanted to make a lot of jam fairly quickly.

I finally understand that thing parents say about loving all of their children equally, even though until I tried to force-rank jam, it seemed like bullshit. I loved all of my jams! They were each unique, with vastly different use cases. If I had to line them up on a stage made out of sourdough toast and hand out ribbons…

• Stovetop Only: Most Efficient (aka Best for When You Want to Fucking Guzzle a Truckload of Jam ASAP)
• Macerate + Stovetop: Best Flavor
• No Cook Freezer: Excellent for Showcasing Naturally Delicious Berries
• No Cook Chia: Truly Easy, a Tiny Baby Could Make It
• Instant Pot: Good for Large Batches & Cooked Flavors
• Sheet Pan: Most Fun to Say & Best If Your Stovetop’s Taken

What should Ella test next? Let us know in the comments, or send her a message here.