Sous Vide Blackberry Jam

Ingredients

• 500g fresh blackberries
• 300g caster sugar
• 30ml lemon juice (2 tbsp, bottled is fine)
• Optional — pick one
• 1 tsp cracked black pepper + 2 bay leaves
• 1 star anise + ½ tsp Szechuan pepper
• 1 small rosemary sprig + ½ tsp black pepper
• ½ tsp shichimi togarashi
• ½ tsp sweet smoked paprika + Maldon pinch

Makes ~600ml jam

Method

1. Macerate. Combine berries, sugar, and lemon juice in a bowl. Stir gently — don't crush. Rest 30 minutes at room temp. Sugar will pull out a deep purple syrup.
2. Heat the bath to 85°C.
3. Fill the jar. Tip the macerated fruit (and any flavourings) into a 1L Weck jar, leaving ~2cm headspace. Wipe the rim clean.
4. Seal loosely. Rubber ring + glass lid + one clamp only. Lets steam escape so the jar doesn't crack.
5. Cook. Lower gently into the bath — water above the jam line, lid can stick out. Weight it down if it floats. 2 hours (up to 3 is fine).
6. Stir. Lift out (tea towel!), open, and stir thoroughly — sugar settles during the cook and needs reincorporating while hot.
7. Cool on the counter 1–2 hours until room temp.
8. Seal and refrigerate. Both clamps on, into the fridge.

Notes

• Whole-fruit texture is normal — sous vide doesn't break the berries down. Mash with a fork after cooking for a traditional spread.
• Loose set is expected. Sous vide can't reach the 104°C pectin set point. For firmer jam, add a tsp of low-sugar pectin, or reduce in a pan for 5 min after.
• Looks liquid hot, thickens cold. Don't judge until it's been in the fridge.
• Don't shock the jar — temper a cold jar in warm water first, or start with a cold bath.
• Pairs with cheese boards (blue, aged cheddar), roast duck, pork belly, scones, yoghurt, ice cream.