These glorious months of raspberries and peaches, blackberries, plums and nectarines inevitably lead me to making jam. I can’t leave a farmers market without pounds of ripe fruit destined for glistening jars lined up in the pantry.
Because I’ve been making fruit jams for most of my life, I know what the bubbles look like when the jam is ready. I recognize the crackle of the spatula as it moves along the bottom of the pot when the fruit is heavy and plump with sugary syrup. And I dance familiar steps processing jars in a water bath so they sit safely on the shelf until fruit season starts again.
It’s just another day in the kitchen, almost a habit, and not tinged with fear of any sort. I want to give you this same confidence — to teach you to cook jam that sets without a worry. I want you to ladle it into jars instinctively and preserve it fearlessly.
It may seem obvious, but to make the most delicious jam, start with the very best-tasting fruit.
My grandmother told me never to make jam with fruit picked after a rainstorm, as the flavor will be watery. I ask to sample the fruit before investing in the 3 pounds needed; no amount of sugar or liquor or spices will help mediocre fruit. I prefer to purchase from local farmers, looking for fruit that has been picked within the past day or two. Making jam from fruit harvested at a pick-your-own farm is satisfying on so many levels, the memories of the day stored in the jar along with the fruit.
Scale and get a printer-friendly version of the raspberry jam recipe here.
Raspberry is the Queen of Jams, so I suggest first-time jam-makers start there. It is one of the easiest jams to make; there is plenty of natural pectin in the fruit, so it reliably sets up. I use a centuries-old European technique and make jam without commercial pectin for a softer set. This technique allows me to safely make and preserve smaller batches using less sugar.
If early summer’s raspberry season has passed, look for wineberries or blackberries, or wait for the autumn raspberries to arrive at the market. Many people prefer jamming with fall raspberries for their deep violet color and wine-like flavor. The recipe ratios provided here work for most any fruit, so substitute at will. All fruit should be weighed before peeling and pitting, making it easy to buy just what’s needed.
Using only fruit, sugar and lemon juice, my technique relies on a rest period during which a fruity, sugary syrup develops and the fruit plumps. After the mixture sits, I separate the fruit from the syrup and boil the syrup to 220 degrees Fahrenheit (the point in candymaking known as the pearl stage), making a thick, sticky and jellylike base to which I add the fruit. By cooking the fruit for less time, it is more likely to retain color and structure.
Making fruit preserves is a matter of boiling a sugary mixture very hard at a high temperature. The common vernacular is “the boil that won’t stir down,” and that’s precisely what you want to look for — a big boil that doesn’t go away when stirred.
Work over high heat, stirring relentlessly. First, small bubbles form and a thick foam covers the surface. As the temperature increases, the foam puddles in islands across the surface and the bubbles get larger, faster, scarier. The sugar might splatter, so I recommend an apron, long sleeves and shoes.
Adjust the heat up and down as needed, but try to work over high heat as much as possible, as the quicker the jam is cooked, the fresher the flavor. It’s possible the contents may rise up right to the top of the pot. Keep stirring to avoid a spillover, and sing “Rise Up” from “Hamilton.” It works for me.
When the fruit is first added to the hot syrup, it will float on the surface. As the mixture comes to a boil and the syrup infuses the fruit, it will weigh more and will be suspended in the syrup. There’s science at work. A foam forms as the water in the fruit is exchanged for the thick syrup. When all but a few bits of foam have disappeared, the water has boiled off, and the jam is ready.
There are two optional additions that will make any jam just a little bit better. Add a pinch of butter at the very end of cooking; those remaining bits of foam will clear, and the jam will be shinier. Additionally, stir in just a little liqueur; it amplifies the flavor. I use Grand Marnier or Cointreau (orange) most often, but amaretto (almond), Frangelico (hazelnut) and creme de violette are delightful, too. In a recent batch, I added amaro, which offered an excellent bitter edge to the sweet jam.
For new jammers, knowing when the jam is ready is the biggest challenge. There are several ways to check the set (see NOTE below). When you’re first starting out, I recommend using all of them.
Every jam-maker has faced jam failure. Instead of spoonable preserves, we end up with a loose sauce or a set so hard it bounces off the toast. Rebranding is key: Loose jam becomes fruit syrup and can be spooned into yogurt, poured over pancakes, puddled around ice cream or stirred into a cocktail. Bouncy jam transforms into a flavorful sauce when whisked (with a dab of mustard) into pan juices and poured over a simply cooked chicken breast.
There is an elephant in the room, so let’s get the whole is-it-safe-to-can conversation out of the way. People have been safely preserving foods for centuries. Jams, like pickles, are one of just a few products that can be safely processed in a water bath. Recipes for preserving in this manner use sugar or vinegar, or both, to adjust the pH to safe levels. Once processed and sealed, the foods can be stored on the shelf for 18 months. At any point, if mold is found growing on the surface of the jam or on the inside of the lid, discard the contents.
I want to encourage you to learn how to can this summer. Yes, it’s hot, and I’m suggesting filling the kitchen with boiling water and boiling jam, and, yes, there is some cleanup, but it’s also an engaging 90 minutes of family time in the kitchen that results in the thrill of pinging lids and sparkling jars lined up on the counter to be admired by all. When I was a kid, an afternoon of jam-making was followed immediately with a joyful run through the sprinkler to rinse off all the stickiness.
Preserving is a masterful technique to have in your kitchen arsenal. It’s time to get your pantry ready for winter with jams, pickles and tomatoes. Start with raspberry jam, which makes only 4 or 5 jars. Enjoy one now, put two in the pantry or barter with your neighbor for some homegrown tomatoes. And then consider what you want to put up next.
How to know when your jam is set
- Turn off the heat, let the boil stop and look for sheeting: When the jam falls from the end of a spatula or spoon more slowly, gathering into a sheet instead of droplets.
- Is the fruit evenly distributed through the jam? If it is floating, return the pan to the heat and continue boiling.
- If the surface wrinkles when gently pushed with a spoon, as though a stone has been tossed onto the surface of a lake, the jam is ready.
- Drop a spoonful of hot jam on a cold plate. Press against it with your fingertip and look for wrinkling and some structure. If the liquid and fruit separate, the jam is not ready. Return the pan to the heat and continue boiling.
- If, when ladled into the jars, the yield is much greater than the expected 4 or 5 jars, the jam is not ready. Return the jam to the pan to continue boiling. Rinse the jars.
Any Fruit Homemade Jam
This recipe for a tart, sweet raspberry jam will also work for blackberries, blueberries, gooseberries, currants, apricots, peaches, plums, cherries and nectarines or any combination. (Weigh stone fruit before pitting and peeling.)
3 pounds (1350 grams) raspberries, about 3 1/2 to 4 pints
3 cups (21 ounces/600 grams) granulated sugar
Juice of 1 lemon
1/2 teaspoon unsalted butter (optional)
1/4 cup (2 ounces/60 milliliters) orange-flavored liqueur (optional)
Place 3 small plates and 3 metal spoons in the freezer to use for the gel test.
Put the fruit in a large bowl. Add the sugar and lemon juice and stir well, making sure no sugar remains at the bottom of the bowl. Cover and refrigerate for at least 2 and up to 24 hours.
Pour the mixture into a colander suspended over a heavy-bottomed 6-quart preserving pan. Let the syrup drip for about 20 minutes, stirring the fruit in the colander from time to time to encourage more syrup to drain. Remove the colander with the fruit, setting it inside the same bowl to capture any remaining syrup.
Place the preserving pan with the syrup over medium-high heat and clip on a candy thermometer. Stir constantly and watch the syrup so it does not scorch as you increase the heat to high.
Bring the syrup to 220 degrees, about 6 to 10 minutes after it starts to boil. It will be foamy with small bubbles at first. The bubbles will get larger and will burst more slowly as the temperature increases. When it reaches 220 degrees, the foam will clear. To avoid scorching, reduce the heat to medium before adding the berries. Remove the thermometer.
If you plan to remove some or all of the seeds from the jam, place a food mill over the preserving pan and mill half or more of the raspberries. Add the rest of the berries directly into the pan as well as any syrup at the bottom of the bowl. Otherwise, add all of the fruit to the pan. Stir well and increase the heat to medium-high.
Bring the jam to a vigorous, slightly terrifying boil where the jam may spatter (hot sugar, be careful) and the entire pan may threaten to boil over. Stir continually to avoid a spillover. Work with the heat under the pot, reducing and increasing as needed, as the jam cooks. Continue to stir; there will be thick foam across the surface of the jam. As the jam boils and gels, the foam will disperse. This process will take anywhere from 25 to 40 minutes.
Lift the spatula from time to time to observe the way the jam falls from its tip. This is called sheeting. At first, the jam will drip, and as it thickens, it will collect, gel and take longer to slip off the spatula. As the foam disappears, check the sheeting continually. When the jam is ready, it will drip thickly and slowly.
When the foam has disappeared, the jam will be thick and the fruit will be dispersed throughout. Turn off the heat. Let the jam sit for 2 minutes and then gently push against its surface with the spatula: It should already be gelling and will wrinkle at the surface. (The jam will firm up a little as it cools.)
Drop a spoonful of hot jam on a cold plate and it should set up as the plate cools it. If the jam is still liquidy, or saucy, after a couple of minutes, turn the heat on again and bring it back to a hard boil. Test the set again and if it is still not gelled, continue to cook the jam, turning the heat off to test the set, and then returning the jam to the heat if it is not gelled.
When the jam is set, add the butter, if using, to remove the last of the foam and clarify the jam. Stir in the liqueur, if using.
While still hot, use a ladle and jar funnel to transfer the jam to jars, leaving a 1/4-inch headspace.
Process in a water bath canner (see related recipe) for 10 minutes, after which it will be shelf-stable for up to 18 months. If not processing, refrigerate the jam and consume within a month. Refrigerate all jams after opening.
Recipe from food columnist Cathy Barrow.
Tested by Cathy Barrow; email questions to email@example.com.
Scale and get a printer-friendly version of the raspberry jam recipe here.
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Calories: 41; Total Fat: 0 g; Saturated Fat: 0 g; Cholesterol: 0 mg; Sodium: 0 mg; Carbohydrates: 10 g; Dietary Fiber: 1 g; Added Sugar: 8 g; Protein: 0 g.