Condiments
Rhubarb jam: the recipe that does not stay runny
Rhubarb is full of water and acid, but has almost no pectin: that is why the jam stays runny. The solution is not a gelling agent; it is cold maceration the night before, which draws out water by osmosis and shortens cooking, plus a grated tart apple. The result is thick, tangy and still pink.
Method
- Wash the stalks, remove leaves and the red base, and cut the rhubarb into 1-1.5 cm pieces. Do not cut it smaller: it would fall apart completely.
- The evening before, mix the rhubarb with the sugar in a large bowl, pour in the lemon juice, cover and leave to macerate for 8-12 hours in the refrigerator. In the morning you will find a pink syrup at the bottom and translucent pieces.
- Strain the syrup into a wide, shallow stainless steel or enamelled cast-iron pot, never aluminium or copper. Set the drained rhubarb aside.
- Bring the syrup to a boil and reduce it for 8-10 minutes over high heat, until it becomes visibly thicker.
- In the meantime, sterilise the jars: boil them for 10 minutes or keep them in the oven at 120 °C for 15 minutes. Always use new lids.
- Add the rhubarb and the grated apple (or the tea bag) to the syrup. If you want a deeper red, add the red currants or strawberries now. Cook for 12-18 minutes over high heat, stirring often and skimming.
- Remove the bag and do the cold saucer test: spoon half a teaspoon of jam onto a saucer kept in the freezer, put it back in the freezer for a minute and run a finger through it. If the surface wrinkles and the groove does not close up, it is ready; if it runs like syrup, cook for another 5 minutes and try again with a fresh saucer.
- Turn off the heat immediately and fill the jars while still hot, up to half a centimetre from the rim. Wipe the rim well, close and leave to cool upright.
- Let cool completely, then check each lid: it must be concave and not click. Write the date on the lid and store in the dark.
Minnelea products for this recipe
The preserves used in this recipe.
Minnelea
Extra Strawberry Jam – Artisan, Preservative-Free
€7,90
Minnelea
Sweet Awakening Kit – 6 Artisan Jams
€39,00
• Rhubarb has barely 0,2-0,5% pectin, compared with about 1% in apple and citrus peel: this, not a cooking error, is why the jam stays runny.
• Acidity, on the other hand, is abundant (malic acid, pH around 3,2): here lemon juice is for color, not for setting.
• Safety: use only the stalks, never the leaves, which contain oxalic acid in high concentration, enough to cause gastrointestinal problems. In the stalks, the same acid is present in much lower quantities, comparable to spinach and beetroot. Cut off the leaves immediately after harvest and send them to the compost, along with the red foot.
• Cold maceration the night before is not a detail: 8-12 hours in the refrigerator with sugar draws out water by osmosis and saves 15-20 minutes of cooking, and therefore color.
• Pectin without a packet: one tart apple grated with its skin for every 1,5 kg, or core and seeds in a tea bag, or 100 g red currants, which also help the color.
• Sugar ratios on cleaned weight: 50% is the reliable classic, 45-47% the compromise in this recipe, 40% or less a decidedly acidic jam, excellent with aged cheeses but with a shorter shelf life.
• The color turns brown for three reasons together: anthocyanins degrade with long cooking, enzymes brown the cut surfaces and sugar caramelizes. Cook over high heat and briefly, do not peel the stalks, use stainless steel or enamelled cast iron and never aluminium or copper.
• Red does not indicate ripeness but variety: a green stalk is just as ripe as a red one, often more acidic, and gives an equally good pink-beige jam. Choose stalks that snap cleanly when bent, with a moist, shiny cut: they are pulled, not cut, and not peeled. Beetroot juice and colorings are not needed; you can taste them.
• Strawberry variation, the most successful: 900 g rhubarb and 600 g strawberries with 650 g sugar. Macerate the rhubarb overnight with two thirds of the sugar and the halved strawberries only one hour before with the rest, then combine them in the last 6 minutes. Strawberries bring sweetness and full red color, rhubarb acidity and structure.
• Ginger variation: 30 g grated during the syrup reduction, so the pungent note softens, and 50 g candied ginger chopped at the last moment.
• The cold-plate test is more reliable than the thermometer: the temperature may be correct while the set disappoints. Hot jam always seems more liquid than it will be, because it firms for another 24-48 hours.
• Storage: with this sugar dose, about 8-10 months closed and kept in the dark, and one week in the refrigerator once opened. After cooling, the lid must be concave and must not click; if it clicks, there is no vacuum, and that jar goes in the refrigerator and is consumed first.
• Allergens: none in the basic ingredients.
• Honest note: rhubarb is not among our labels and will not be, because our farm is in Cilento and rhubarb wants a cold, rainy spring. If you want to taste the strawberry side of the classic pairing, the closest reference is our Extra Strawberry Jam.
A Minnelea recipe built around Extra Strawberry Jam: low-temperature vacuum cooking, real fruit and short ingredient lists, with no added pectins, preservatives or colorings.
• Acidity, on the other hand, is abundant (malic acid, pH around 3,2): here lemon juice is for color, not for setting.
• Safety: use only the stalks, never the leaves, which contain oxalic acid in high concentration, enough to cause gastrointestinal problems. In the stalks, the same acid is present in much lower quantities, comparable to spinach and beetroot. Cut off the leaves immediately after harvest and send them to the compost, along with the red foot.
• Cold maceration the night before is not a detail: 8-12 hours in the refrigerator with sugar draws out water by osmosis and saves 15-20 minutes of cooking, and therefore color.
• Pectin without a packet: one tart apple grated with its skin for every 1,5 kg, or core and seeds in a tea bag, or 100 g red currants, which also help the color.
• Sugar ratios on cleaned weight: 50% is the reliable classic, 45-47% the compromise in this recipe, 40% or less a decidedly acidic jam, excellent with aged cheeses but with a shorter shelf life.
• The color turns brown for three reasons together: anthocyanins degrade with long cooking, enzymes brown the cut surfaces and sugar caramelizes. Cook over high heat and briefly, do not peel the stalks, use stainless steel or enamelled cast iron and never aluminium or copper.
• Red does not indicate ripeness but variety: a green stalk is just as ripe as a red one, often more acidic, and gives an equally good pink-beige jam. Choose stalks that snap cleanly when bent, with a moist, shiny cut: they are pulled, not cut, and not peeled. Beetroot juice and colorings are not needed; you can taste them.
• Strawberry variation, the most successful: 900 g rhubarb and 600 g strawberries with 650 g sugar. Macerate the rhubarb overnight with two thirds of the sugar and the halved strawberries only one hour before with the rest, then combine them in the last 6 minutes. Strawberries bring sweetness and full red color, rhubarb acidity and structure.
• Ginger variation: 30 g grated during the syrup reduction, so the pungent note softens, and 50 g candied ginger chopped at the last moment.
• The cold-plate test is more reliable than the thermometer: the temperature may be correct while the set disappoints. Hot jam always seems more liquid than it will be, because it firms for another 24-48 hours.
• Storage: with this sugar dose, about 8-10 months closed and kept in the dark, and one week in the refrigerator once opened. After cooling, the lid must be concave and must not click; if it clicks, there is no vacuum, and that jar goes in the refrigerator and is consumed first.
• Allergens: none in the basic ingredients.
• Honest note: rhubarb is not among our labels and will not be, because our farm is in Cilento and rhubarb wants a cold, rainy spring. If you want to taste the strawberry side of the classic pairing, the closest reference is our Extra Strawberry Jam.
A Minnelea recipe built around Extra Strawberry Jam: low-temperature vacuum cooking, real fruit and short ingredient lists, with no added pectins, preservatives or colorings.