Once known primarily as jelly’s understudy on peanut butter sandwiches, jam has surpassed the second slice of bread. It’s the rainbow atop the “famed ricotta toast” at LA’s Sqirl, which also sells a bimonthly jam subscription and just announced plans for a jam book slated for April 2020. It sits on the shelves of artisanal, gourmet shops, alongside signs announcing the region’s fleeting specialties: you’re in sour cherry country, now, shopper. It even merits its own little bowl on cheese boards. These days, we’re slathering sweet preserves on our food from the first cup of coffee in the morning until the last glass of wine at night.
This means home cooks might find themselves eyeing a half-empty jar of apricot basil jam and thinking, “I could do that for less than $12.” Spotting an abundance of figs on a local tree may spark a desire to turn the end-of-summer treat into something to savor in the winter. With the right tools, it can be done — and all within the course of a single afternoon.
There are many methods of preserving fruit (like making freezer jam), but water-bath canning is commonly thought of as the best method for high-acid fruits, and the one we’ll focus on here. Because it’s been around for ages, jam-making is the kind of endeavor that lots of people have assumptions about. For example, the idea that you should buy fruit that’s past its prime for canning is a myth, says Lauren Sandler, director of preservation of Baltimore’s Woodberry Pantry. “You want to be working with product that’s gorgeous, that you would want to eat yourself.”
Sandler says people often think about canning as a day-long process, requiring flats of fruit. Working with smaller batches, like 2-3 jars of jam at a time, is a way for beginners to ease into the process. “It’s definitely a big set-up and if you have a smaller kitchen, you’re going to be moving things around,” she says. “But it will get you into the motion of it all: the muscle memory and understanding the basics.”
To get a better understanding of canning techniques and safety protocols Sandler recommends the Ball Blue Book Guide to Preserving, from jar company, Ball. Now in its 37th edition, she calls it “super informative.” It contains tested recipes, as well as how-tos, like jar and lid sterilization, details on water temperature, and guidelines for the proper jar headspace (the space between the jam and the top of the jar). With this instruction manual in hand, here are the tools you’ll need.
The material of the pot you’ll use to cook your fruit is critical to consider; aluminum, for example, can react with the acid in the fruit. Alessandra Gordon, owner of Seattle-based jam company Ayako and Family, likes to give home cooks two suggestions when it comes to jam-making pots: one copper, one stainless steel.
“The copper, in particular, is a really great conductor of heat,” she says. Gordon notes the shape of the pot is also important when working with fruit at high heat. “If you have a rounded pot, you’re really able to make sure you’re getting the entire surface area heated to the exact same temperature. And when you’re stirring, you’re moving that fruit around, as opposed to it getting stuck anywhere.” And when fruit gets stuck in, it’s likely to burn. The Mauviel Hammered Copper Jam Pan from Williams Sonoma will prevent that from happening.
When Gordon’s mother started the company back in 2009, she used a stainless-steel All-Clad saucier to cook the organic jams. If more moderately priced stainless steel is your preference over copper, try All-Clad’s d3 Stainless Steel Saucier in the two-quart size.
Heat is always a factor when making jam, and Gordon uses a long-handled ladle when stirring the fruit. “It gets really hot over the stove, so having your hand as far away from the actual fruit as possible is always safer.” Once again, the material is important: Opt for this 15-inch stainless steel version and be sure to stir enough to prevent sticking.
Even if you’re following your recipe and paying close attention to your fruit, Sandler says, the acidity, sugar levels, and water contact can all influence how the fruit reacts to the cooking process. A candy thermometer, like this stainless steel option, helps ensure you cook it to the required 220 degrees.
16-ounce Ball jars
For the actual jam vessel, Sandler prefers the classic 16-ounce Ball jar with a wide mouth. As mentioned above, you’ll only need a few jars, but they are often sold by a set of four or 12, and they’re cheaper to buy in packs. “If I could use those for the rest of my life, I would,” she says.
Jar-grabber and magnetic rod
Brian Noyes, owner of Red Truck Rural Bakery in Virginia and author of Red Truck Bakery Cookbook (with Nevin Martell), recommends getting a canning kit, like the six-piece Norpro Canning Essentials Boxed Set, for all the little essentials that allow you to fill and bathe the jars in boiling water. “Don’t laugh at those assembled kits of tools for canning or jelly-making because they really work well,” Noyes says. The jar-grabber and magnetic rod will all make the canning process easier and safer, as you’re dealing with boiling water and molten jam. “Don’t you think your grandmother would just roll her eyes at that? But,” Noyes adds, “it all exists for a reason.”
When you’re putting the lid on your sterilized jars, make sure the rim of the jar is completely clean. A funnel can help with this process. Gordon, for example, uses a confectionary piston to control exactly how much jam goes into each jar.
“If there’s something obstructing it, you’re not going to create a hermetic seal, because you can’t seal the jar if there’s something in the way,” Sandler says. She also says it’s important not to mix and match lids and jars, as you might not be able to get that critical seal if they’re not an exact pair.
Big pot with a metal rack
After you’ve filled the jars and put on the lids, you can begin processing the jars in a bath of boiling water. “You need to make sure the jars are cushioned somehow, whether it’s with a metal rack or I’ve seen people use a towel (though I’ve never done that myself),” Sandler says. “If you put a hard jar full of liquid that’s going to be getting to a very hot temperature on some type of object that’s going to be banging around, you’re going to crack your jar.” This Granite Ware canner comes with a rack and is big enough to hold seven of the 16-oz. Ball jars.
Noyes also always keeps stacks of newspaper on hand, to sop up the water when pulling jars out of the bath. (Fitting, given that he used to be an art director at the Washington Post, which is where he was working when he created his grand champion peach jam recipe.) A roll of paper towels and a tea towel also help keep the canning process clean.
But just as important as the right gear, is a reliable recipe. “Canning is pretty nuanced, but I always tell people, keep trying,” says Gordon. “You have to find a good balance and test recipes out.”
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