Strawberry jam
The beliefJam is imagined as an all-day, jar-after-jar production.
The truthIt is a balance of three things: pectin, acid and sugar. Get the balance and it takes forty minutes.
How to make it
What you need
- 1 kg strawberries
- 600–700 g sugar
- Juice and zest of 1 lemon
How the engine read this list (3 lines)
| 1000 g | Strawberries | strawberry |
| 650 g | Sugar | sugar |
| 40 g | The juice and zest of a lemon | lemon |
An empty weight means that line could not be turned into grams — either the amount is open ("to taste") or the ingredient has no record here. Neither enters the sum as zero; they do not enter it at all.
Toss the strawberries with the sugar and leave them, covered, for two hours. Osmosis pulls the water out and the syrup forms itself, so the fruit holds its shape when it cooks.
Boil hard in a wide pan. Width matters: the bigger the surface, the faster the water leaves and the less the fruit overcooks.
Add the lemon juice and zest in the last five minutes. Put the acid in at the start and long boiling breaks the pectin down.
Check at 104–105 °C. No thermometer? Use the cold plate test: drop a spot onto a plate from the freezer, wait 30 seconds and push it with a finger — if it wrinkles it is ready; if it runs, boil three more minutes.
Fill hot jars with hot jam, close them and cool them upside down. The vacuum forms on its own.
The others that work the same way
Tomato paste
The truthThe only job is taking the water out. Three hours in the oven or two days in the sun — the work is identical either way.
Pomegranate molasses
The truthYou boil pomegranate juice down to a fifth. The only decision is when to stop.
Grape molasses
The truthThe grape’s own sugar is enough. You clarify the must with earth and boil it down to a third.