Strawberry Jam

“Neither my mother nor her contemporaries had recipes as a recipe is counted today. They had ‘rules’, but many of their rules were in their fingers and eyes.” (Della T. Lutes from The Country Kitchen (1936)

Making jam is an example of cooking by feel. Most commercial jams contain modified pectin. Manufacturers modify natural pectin by using chemicals or enzymes to standardize their product and give it shelf stability. They also produce modified pectins made specifically for home jam-making.

However, homemade jam may be made without modified pectin, sugar, or artificial sweeteners. It needs only slow cooking and then…let your senses be your guide–judging by touch, consistency, and appearance when the berries have turned into jam.

Homemade jam, made with or without sugar and pectin, will lose some moisture and thicken over time. This is normal and does not mean the fruit was cooked too long or the ingredient combination was faulty. This is simply what good jam that is primarily fruit (and not a standardized formulation of different sweeteners and ingredients) does once it has been stored in the refrigerator. In the past, home cooks never expected their jam to remain exactly the same. They stirred the jam and added a little liquid to bring it back to its original consistency, as is still done today. Stirring in a small amount of apple juice will soften the jam.

The less processed ingredient options used to make the jam are: Frozen Strawberries, Homemade Apple Juice Concentrate, Apple Juice, European-Style Unsalted Butter, and Unmodified Potato Starch.

Equipment

a Medium-Sized Pot with a Heavy Bottom and Lid
a Wooden Spoon
a Liquid Measuring Cup
a Large Bowl
a Whisk
a Flame Tamer (aka Heat Diffuser, Simmering Plate). The pot does not sit directly over the heat source and the jam can cook down very slowly over an even heat. Some versions of flame tamers are compatible with a smooth-top burner,
an Immersion Blender or a Food Processor with the Blade Attachment
Glass Containers for storing the jam in the refrigerator: There will be around 3 cups (or 960 g) of jam.

Ingredients

3 Pounds of Frozen Strawberries, thawed (1.36 kg) and their juice
1 Cup plus 1 Tablespoon of Homemade Apple Juice Concentrate (240 ml plus 1 Tablespoon): The foodlessprocessed recipe for concentrate is here: Apple Juice Concentrate.
4 Tablespoons total of Unmodified Potato Starch
3 Tablespoons (42 g) of European-Style Unsalted Butter

Making the Jam

Three pounds of berries will make about 3 cups of thick, dense jam (or about 960 g). For this relatively small amount, there is no need to go through a canning process.

Drain the juice from the berries into a measuring cup. If there is 1 cup or more of juice, pour it all into the pot. If there is less, add some extra apple juice concentrate to make 1 cup.
Pour the berries into a bowl and roughly break them up with an immersion blender or, instead, break them up a bit in a food processor. Bits and pieces of berry will still be in the mix. Set the berries aside.
Add 3 tablespoons of the potato starch to the juice in the pot and whisk until the mixture is smooth.
Add the butter. Place the pot on the flame tamer and cook over low heat to melt the butter, stirring often.
Add the berries and 1 cup (240 ml) of the apple juice concentrate. Cook over the lowest heat, partially covered. Stir the mixture now and then with a wooden spoon, scraping the sides and bottom of the pot.
At the end of 2 and 1/2 hours, mix together the remaining tablespoon of potato starch with the remaining tablespoon of apple juice concentrate and add them to the simmering berries.
Continue to cook the mixture down, stirring occasionally.
Look at the mixture as you stir it and feel its consistency. At the end of the first 2 and 1/2 hours it will still be a cloudy pink colour and will stir like a sauce.
The berry mixture will gradually darken and thicken, first to a very thick sauce of the sort one might use to fill crêpes. In time its colour will deepen to a brownish-red and the consistency will be “jammy”, that is, it will stir and unquestionably look like jam. The estimated total time for this transformation is about 4 and 1/2 hours.
When the jam is done, remove it from the heat, transfer it to containers (preferably glass ones) and, when cool, lid the jars of jam and refrigerate them.