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How to Rescue a Batch of Homemade Jam

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Check out these jam recipe rescues for fruit low in pectin.

Check out these jam recipe rescues for fruit low in pectin.

Jam Recipe Rescues for Fruit Low in Pectin

Fruit that is naturally low in pectin requires special ingredients and attention to make a firm-textured jam. Over the years, I have had the most trouble making jams and jellies with low-pectin fruit such as blueberries, oranges, rhubarb, and pineapple.

These low-pectin batches of jam fail for me most often by not jelling properly. I end up with thin blueberry-flavored syrup. The recipes for these jams and jellies explain how to add enough pectin. Jam recipes for these low-pectin fruits rely on these standard tactics:

  • Use a higher ratio of commercially prepared pectin and lemon juice to fruit juice (1 box per 3 cups of blueberry juice as compared to 1 box per 7 cups of concord grape juice).
  • Include underripe fruit.
  • Include high-pectin fruit and lemon juice (heirloom combinations like pineapple apricot, strawberry rhubarb).
  • Include high-pectin odds and ends boiled with the juice and removed before finishing the recipe (orange pips boiled with marmalade, apple peels, and cores boiled with other juices).
  • Reduce the water content of the fruit (by draining all or part of the low-pectin fruit or boiling down the low-pectin juice before proceeding with the recipe).
  • Use alternatives to pectin like gelatin, corn starch, or agar-agar (Japanese kanten).

To rescue a batch of jam or jelly that looks like it might not gel all the way, do what the chefs who developed the recipes did, only better. Here is my set of test recipes and stories of rescued batches of jam.

Blueberries pose special challenges to jam and jelly makers.

Blueberries pose special challenges to jam and jelly makers.

Correct the Ratio of Liquid to Sugar and Pectin

My usual plan for restoring a batch of jam that did not turn out is to correct the ratio of liquid to sugar and pectin. If I follow a low-pectin recipe exactly and end up with syrup, I usually add 1/2 teaspoon more lemon juice per 4 cups of fruit juice in the original recipe and boil the syrup longer to reduce it. That repair process intensifies the fruit flavor, although it reduces the yield (amount of jam produced in the recipe).

Blueberry Jelly

I most recently tried this method on a new recipe for blueberry jelly:

  • 1 medium Golden Delicious apple, peeled and diced
  • 1/2 cup frozen blueberries
  • Sufficient commercially bottled blueberry juice added to the fruit to make 4 cups (have about 3 cups on hand)
  • 2 tablespoons lemon juice
  • 1 box pectin
  • 5 cups sugar


  1. Mix the fruit, blueberry juice, lemon juice, and pectin. Stir to dissolve the pectin.
  2. Bring to a boil over high heat. Add the sugar all at once and boil.
  3. Return to a boil and boil for exactly one minute.

(At that point, I had syrup. I had to boil the syrup for an additional 30 minutes to reach the jelly stage.) The yield was 3-pint jars of jelly plus about 1/2 cup.

Reducing the blueberry juice produced a stronger-flavored jelly than I expected from a commercially prepared juice. Although I could probably adjust the recipe to include a total of 3 cups of fruit and juice and the same quantities of sugar and pectin, I think I'll stick with the reduction process for a better flavor.

To accomplish the same goal without affecting the yield, add more sugar, pectin, and lemon juice in the same proportion called for in the recipe to correct the ratio. This process is trickier but comes in handy when it is of the utmost importance to make the exact amount of jam you had planned on.

Try measuring out the sugar, pectin, and lemon juice called for in the recipe. Then add 10 percent of the sugar, pectin, and lemon juice at a time, all at once, boiling for one minute after each addition until the jelly stage is reached. Hint: To divide the lemon juice evenly without measuring spoons, freeze it and cut it into equal portions.

Add High-Pectin Fruit to the Recipe

It is common to combine varieties of fruit with different pectin contents to help assure the success of a jam batch. Apples are high in pectin and cost less than peaches and berries. Apple varieties such as Golden Delicious, Cameo, Gala, and Arkansas Black provide excellent texture elements as well as unique floral, honey, and spice aromas to the finished jam.

I think of using apples as improving the texture, not substituting inferior ingredients to reduce its cost. Even so, apples do cost less. They also carry the color and flavor of berries, cherries, and other bright fruit so well that I can substitute apples for 1/3 to 1/2 of the fruit called for in a recipe. For a more decadent jam, and when a light golden color is as important as a rich flavor, consider fresh apricots or white grape juice to add pectin and body to the finished jam recipe.

If you've made a batch of jam according to the recipe that came with the box of pectin, and it has turned out syrupy, try combining it with half a batch of high-pectin jam or jelly. Chose from among the recipes listed by your pectin manufacturer calling for 6 or more cups of fruit per box of pectin. Add the ingredients for the half batch to your first batch, and boil, stirring constantly, until the jelly stage.

Raspberries lend themselves especially well to freezing and freezer jam because of their low tannin content.

Raspberries lend themselves especially well to freezing and freezer jam because of their low tannin content.

Include Underripe Fruit in the Recipe

Underripe fruit has a higher pectin content and keeps its texture during cooking. So even though it might not have the best flavor eaten fresh, underripe fruit makes excellent jams and preserves. The classical ratio of fruit sorted by ripeness for jams and preserves, including for peaches, figs, and blueberries, is 1:2:1.

  • 25 percent underripe fruit for its higher pectin content and firm texture
  • 50 percent ripe fruit for its perfect flavor
  • 25 percent slightly overripe fruit for its juiciness and fragrance

When I buy boxes of peaches for preserves at the roadside farmer's market about 60 miles out of town, they pack the boxes according to that 1:2:1 ratio without being asked.

To make a stiffer jam or enjoy a higher yield with the same quantity of fruit, I use at least a 1:1 ratio of underripe fruit to combined ripe and overripe fruit.

When I make blueberry jam, at least half my blueberries are red, and I include the green ones as well. A few little green blueberries are a real treat in jam because they are usually too young for the seeds to develop fully. In the finished jam, they are tiny, tender whole blueberries. They lend their tartness and pectin to the finished jam and take on its sweet fragrance instead.

Here is the recipe for the last blueberry jam I made with underripe fruit.

  • 1 1/2 cups underripe blueberries (red and green ones)
  • 1 cup ripe blueberries
  • 1/2 cup diced apple (peel and core optional)
  • 2 tablespoons lemon juice
  • 1 box pectin
  • 5 1/4 cups sugar

Crush the ripe blueberries. Mix all blueberries, apples, lemon juice, and pectin. Include the apple core and peel for extra pectin if they would be easy to remove before bottling the jam. Bring to a boil over high heat. Add the sugar all at once. Return to a full rolling boil and boil for one minute. Test for the jelly stage, and boil a little longer if necessary until the jelly stage is reached. Remove the apple peel and core if used.

My favorite recipe for peach preserves calls for about 15 pounds of peaches and 5 pounds of sugar. Lemon juice is optional. I would rather leave it out and accept a darker color in exchange for a more gentle flavor.

  • 15 pounds peaches (including at least 7 pounds of hard underripe peaches)
  • 5 pounds sugar
  • 1 cup water

In a heavy-bottom kettle, boil the sugar and water to form a syrup. Reduce heat to a simmer. Peel the peaches 3 to 5 at a time (or work with a partner who can peel while you cook). Halve the ripe peaches. Slice the underripe peaches to promote quick and even cooking. Simmer the prepared peaches in the syrup a few at a time until they are tender: "so tender a broom straw would slide right through," according to the New Orleans Times-Picayune Cookbook. Remove each batch of peaches from the syrup and keep warm.

Return the liquid that rises from the finished peaches to the pot of syrup as it accumulates.

Process all the peaches in this way, halved ripe peaches first, then sliced underripe peaches. When all the peaches are done, simmer the remaining peach syrup until it is thick and reaches the jelly stage. Return all the peaches to the syrup and return to the boil. Check for doneness. Preserves, especially old-style ones like this, are usually cooked a little softer than a typical jam or jelly. Cook to the jelly stage if you like, but I usually stop while they are thicker than canned peaches but not quite as thick as jam.

In this recipe, the unripe peach slices retain a firm texture and stronger peach flavor during cooking, and they thicken the preserve syrup with less water loss from boiling down the preserves. I get about an extra 8 ounces of preserves per 5 pounds of underripe peaches I substitute for ripe peaches in the recipe.

The right way to eat peach preserves is to reach in with a fork, spear yourself a plump peach half, and eat it right out of the jar!

Apples are high in pectin.

Apples are high in pectin.

Boil High-Pectin Items With the Jelly and Discard Them

I picked up this tip in an English book of French recipes. The recipe involved making a glaze for an apple tart by boiling the cores and peels from 5 apples in 1 1/2 cups of apple cider.

It said to arrange five beautifully pared and sliced apples in a tart shell lined with apple sauce and their cores and peels to make a glaze while the tart bakes.

Since then, I include apple cores and peels in my plum preserves and remove them before bottling the preserves.

  • 2 to 3 pounds prune plums (sometimes called Italian or French plums)
  • 1 pound Golden Delicious apples, pared and sliced
  • 5 cups sugar
  • 1/2 cup water

Boil the sugar and water to form a syrup. Reduce heat to a simmer. Rinse and halve the prune plums. Boil about 2 cups at a time in the syrup until they are translucent and soft. Set the cooked plums aside and keep warm until all are cooked. The skin will come loose after giving its lovely color to the syrup. I leave the skins out of the finished preserves because they are tough.

When the plums are done, process the apples, with the cores, apple skins, and plum skins, in the plum syrup until the apple sections are translucent. Return the plums to the syrup. Boil until the preserves are just shy of the jelly stage. Remove the cores and skins.

This idea of boiling odds and ends that are high in pectin and throwing them away is typical of marmalade as well. Orange pips (seeds) are high in pectin. The oranges and lemons that make the best marmalade have a lot of seeds. I hear bitter Seville oranges are best for marmalade. Still, I usually use Valencia oranges because they are available in my market. Unlike navel oranges, the juice from Valencia oranges retains a pleasantly sweet flavor when heated.

I usually reserve the seeds of a few extra oranges to add to a batch of marmalade and filter them out at the end. Just for luck. I have such trouble with marmalades!

Reduce the Water Content of the Fruit

My friends in Alaska would make their raspberry jam with half fresh-picked berries and half frozen berries. They would thaw and drain the frozen berries for about 3 hours before crushing the berries for jam recipes involving commercial pectin.

For example, in a 4-cup jam recipe, they would use 2 cups crushed fresh raspberries and 2 cups thawed drained berries.

Raspberries lend themselves especially well to freezing and freezer jam because of their low tannin content. Raspberries do not turn brown and develop off flavors after freezing and thawing. Blueberries, apples, pears, and peaches, on the other hand, do tend to discolor during repeated freezing and thawing. A little extra lemon juice or "fruit-fresh" (a commercial citric acid product) can limit the discoloration while only slightly affecting the flavor.

Boiling is another way to reduce the water content of a fruit mixture so that it performs better in jams and jellies. I typically reduce commercial fruit juices by 20 to 25 percent before using them in a jelly recipe. If a homemade juice that you made by boiling fruit tastes weak compared to your usual results, boiling it a little longer may assure the success of the jelly made with it later on.

If fruit with subtle and complex perfume is key to the success of the jam or jelly, then excessive boiling is not advisable. Jellies featuring honey, mint, rosewater, violets, or perfectly ripe fruit can lose some of their charm if the key ingredients are boiled too long. In that case, it might be preferable to follow the recipe exactly or attempt one of the rescue techniques involving less heat and cooking.

Kanten jelly treat

Kanten jelly treat

Use Alternatives to Pectin

Sometimes a jam or jelly is not the best way to present the texture and natural juiciness of a fruit. Gelatines and seaweed-based gelling agents such as kanten (agar-agar) come into play when lighter flavors or less sugar per serving is desired. Unflavored gelatine can also come in handy to solidify a syrupy batch of jam (keep it refrigerated).

Here is a recipe for a syrupy jam or jelly rescued by stiffening it with unflavored gelatine.

  • 4 cups jam or jelly syrup
  • 1 envelope unflavored gelatine
  • 2 tablespoons water

Soak the gelatine in the water for 5 to 15 minutes, according to the package directions. Add the soaked gelatine to 2 cups of the syrup and heat until the gelatine is dissolved. If the mixture comes to a boil without fully dissolving the gelatine, add more syrup and continue heating for 1 or 2 minutes more. Remove from heat. Stir in the remaining syrup. Pour into jars or a mold and refrigerate until ready to use. Best served cold. Jam thickened with gelatine tends to melt when spread on hot toast or warm thumbprint cookies.

Kanten is a seaweed-based agent that is becoming more widely available. Its advantages are that it forms a firm, bright jelly that is stable up to at least 130°F. Kanten is widely used in Asia to make gelatine desserts that showcase ingredients that are relatively low in acid, like peaches, lychee, coconut, mango, red bean paste, and pudding.

Strawberry-rhubarb jam with gelatine is great on waffles.

Strawberry-rhubarb jam with gelatine is great on waffles.

Strawberry-Rhubarb Jam With Gelatine

My favorite example of gelatine used to draw attention to fresh flavors is the strawberry-rhubarb jam my friends make in Alaska. The recipe depends on the quick cooking time and high water content of a gelatine to allow the tart freshness of rhubarb to mingle with the sweetness of strawberries.

  • 1 envelope strawberry gelatine to serve 4 people (sugared or sugar-free)
  • 1 pound frozen strawberries
  • 2 cups sliced rhubarb
  • 1/4 cup water

Simmer the rhubarb in the water until it is tender. Remove from heat. Add the strawberry gelatine, and stir until the gelatine is dissolved. Stir in the frozen strawberries and chill until serving time. This jam should be fairly loose and soft. There is no need to overcook the rhubarb. It should taste tart and fresh in the finished jam.