Get Into a Jam

The secret to making fruit preserves that truly sing

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HOMEMADE JAM

TRANSFORMING FRUIT INTO JARS of homemade jam can feel like a magic trick, and there is a kind of magic in the age-old craft. Rather than using a box of processed pectin, the finest jams rely on evaporation and the fruits’ natural pectin to achieve a luscious, spoonable texture. The difference between mediocre jam and one that truly sings lies in a few key elements: impeccable fruit, a good balance of flavors, and proper technique.

This may come as a surprise, but perfectly ripe fresh fruit for eating is not ideal for jam-making. That’s because as fruit ripens, its pectin levels decrease. For the best jam, choose fruit that is ripe but still slightly firm. Frozen fruit, which is usually picked somewhat firm, also works well for making jam.

To jump-start the process, first macerate the fruit with sugar and lemon juice—this precooking step draws out the fruit’s juices and results in shorter cooking times. (If working with frozen fruit, cover it with sugar before defrosting to help maintain its shape and structure.) The lemon juice boosts pectin, helping the jam to achieve a perfect gel, while also adding acidity, which prevents it from veering too sweet.

Once your fruit is ready, cook it in a wide pot-this allows the jam to thicken quickly, locking in the vivid, fresh flavors of the fruit. Varying levels of water content and natural pectin cause some fruits to cook quicker and set at a slightly lower temperature than others. (See “Fruit Cooking Times and Temperatures” at right.) Once the jam is on the stove, err on the side of undercooking. You don’t want the jam to shift in color, from bright to brown-this signals that the sugar has caramelized and the delicate fruit flavor has been lost.