How to make jam without canning
It took me an embarrassing number of years to overcome my (unreasonable) paranoia about making jam that would somehow give my friends and family botulism. The nasty, if rare, illness — which can lead to paralysis, death, etc. — is caused by a toxin generated by bacteria that can thrive in improperly canned food.
By the time I mastered canning and eventually slid into an annual groove, I had a baby and no longer had the time to go through the traditional waterbath canning process.
That’s why refrigerator jam has now become my (sorry!) jam. It’s an easy, no-stress and quick method that bypasses the whole practice of having to sterilize and boil a bunch of jars.
“There’s no judgment if you don’t want to do the water-bath canning process,” says Marisa McClellan, the three-time canning cookbook author who blogs at Food in Jars.
Ready to try it? Here’s how to get jamming.
Pick the right fruit
In the height of summer, you can’t go wrong with stone fruit. Peaches and nectarines are especially ideal because they tend to be cheaper and ripen quickly, McClellan says. You can use almost any fruit you like, though at other times of the year, you want to avoid very firm fruit such as apples or quince that won’t soften in the short cooking time. Aim for four cups of fruit cut in a moderate dice. Bigger pieces can be mashed a bit once the fruit starts to break down in the skillet. You don’t have to worry about peeling most fruit, although McClellan suggests you do so with peaches since the skins don’t break down particularly well. (The best way to peel peaches is to first boil them briefly until the skins begin to burst, then dunk them in ice water. The skins should slip off easily.)
As to the state of your fruit, very ripe is fine. But “truly rotten fruit — turning it into jam isn’t going to make it better,” McClellan says. “It still has to be fruit you’re interested in eating.”
Sweeten it
McClellan recommends going with a 2-to-1 ratio of fruit to sugar. So I used 4 cups of fruit and 2 cups of sugar for the jam I made (the yield of the jam was about 2 cups). If your fruit is very ripe and sweet, you can use closer to a 3-to-1 ratio. If you choose something like honey instead of granulated sugar, reduce the amount by a third, since it is a more concentrated sweetness, McClellan says.
Flavor to taste
You can certainly stick with the simplicity of fruit and sugar. Or you can start to experiment with different flavors. One of McClellan’s favorite cheats is to use a teaspoon of pumpkin pie spice. It’s a great way to use that jar you probably only pull out once a year anyway, plus it saves you the work of measuring out a bunch of different spices. Try a splash of almond or vanilla extract just before the jam finishes cooking. Put whole spices (cinnamon sticks, star anise) in at the beginning and remove once the jam finishes cooking.
Get cooking
“The goal is hot and fast when you’re making these small batches of jam,” according to McClellan. Using a wide skillet encourages quick cooking and evaporation of moisture. A stainless-steel skillet is perfect. Enameled cast-iron works well, too. Stay away from regular cast-iron, though, because it is “reactive,” meaning it can impart off flavors to the jam. Nonstick isn’t ideal either, McClellan says, because the coating can be prematurely aged by the heat at which you need to cook the jam.
What heat is that? Typically high, she advises, although if your stove top is really powerful, you may want to dial the temperature back to medium-high or even medium. The amount of time you want to cook the jam will vary depending on the vessel, the ripeness and moisture content of the fruit, and how much and what type of sweetener you’re using. A good rule of thumb is 8 to 15 minutes, though to be sure you should look for one major cue: The jam, when stirred — a silicone spatula is a good way to go, McClellan says — should create a trail that does not close up right away.
Store it
There’s no need to sterilize whatever you want to put the jam in, as with water-bath canning, but it should be clean. Glass jars, the type you use for canning or even cleaned jars that previously held store-bought jam, are great. McClellan also likes lidded Pyrex containers. You can even use plastic so long as you let the jam cool first before pouring it in to avoid melting anything.
A refrigerator jam isn’t going to last forever. While you don’t need to worry about botulism (the bacteria only thrive in an anaerobic, or oxygen-free, environment), mold is a possibility, as with any open food. As long as you are scrupulous about not getting other food or “nasty bits” in the jam, McClellan says, it should last a month in the refrigerator.