Making Jam and Jelly

By Tami Schlies

Jams and jellies are a fine balance of four essential ingredients; fruit, pectin, sugar, and acid.  Each type of fruit provides at least some natural pectin and acid, with slightly under-ripe fruit providing slightly more than the fully ripe counterpart.  This is why many recipes suggest using about one-fourth under-ripe fruit, so the fully ripe fruit balances the flavor of the sugar, while the less ripe fruit helps gel the mixture.  Over-ripe fruit will yield runny jelly or jam.

Pectin is concentrated in the skins and cares of various fruits, which is why many recipes boil the whole fruit to make the juice for jelly.  Excessive cooking – too slow or too long – can reduce the gelling property of any pectin.  This is also why boxes of commercial pectin require you to work in small batches, as the longer cooking time required to heat larger batches zaps the pectin into uselessness.  Today most commercial pectin is made from the white inner part of citrus fruits, but in the old days apple juice was added to less pectin rich fruits to make them gel.

Like pectin, acid is an essential component in the gelling of fruits.  Many recipes call for the addition of lemon juice in order to bring the acid ratio into balance.  To determine if the fruit you are using needs lemon juice, compare the flavor of your fruit juice with the tartness of a mixture of 1 t. of lemon juice, 3 T. water, and ½ t. sugar.  If the juice is not tart enough, add lemon juice before making jelly – up to one tablespoon per cup of fruit juice.

The final component of jam or jelly is sugar.  Sugar helps the gel to form, is a natural preservative, and for most people improves the flavor of the product.  I myself prefer the flavor of the fruit to shine through, which is why I like Pomona’s Universal Pectin, a low-methoxyl pectin that uses calcium to boost gelling power with less sugar.  I use this for sweet fruits like strawberries and raspberries.  However, very sour fruits, such as currants or wild blueberries, require more sugar, and I make jam and jelly without added pectin for these fruits.  To make these fruits gel, sugar is added in an almost cup per cup ratio with the juice.  I make a wonderful, rich currant jelly with nothing but 4 cups of fruit juice and 3 cups of sugar cooked to 220 F on a candy thermometer.

An example of a few fruits that have enough natural acid and pectin to gel with only sugar include crabapples, cranberries, currants, gooseberries, lemons, wild blueberries, and plums.  Sour cherries may have enough pectin and acid if they are not over-ripe, as well as chokecherries, elderberries, and grapes.  Fruits that always need added pectin and acid include apricots, peaches, pears, prunes, raspberries, and strawberries.

For those who don’t like to rely on the grocery store pectin to make jam or jelly, you can make your own liquid pectin out of apples.

Pectin can be used right away or frozen in small amounts (half or whole pints) or canned for future use.  To use it, add 4-6 tablespoons of pectin per every cup of prepared juice (experiment first with the pectin).

Crabapple pectin

2 pounds sliced, unpeeled crabapples

3 cups water

Simmer while stirring for 30 or 40 minutes, adding water as needed.  Put the mash into a colander lined with cheesecloth and set it over a bowl and squeeze the juices through.  To clear the juice, heat it and pour it thorough a jelly bag that has been pre-moistened in hot water.

Tart Apple pectin

4 pounds sliced apples with peels and cores

8 cups water

Simmer for 3 minutes.  Press apples through a sieve to remove cores and skins.  Return juice to pan and boil until reduced by half.  Clarify as above.