Pickled French Beans

When the bean poles are cropping faster than anyone can eat, a batch of sharp dill-pickled beans turns a week's picking into jars for the winter. This is a tested recipe for whole pods in a vinegar brine, finished with a short spell in boiling water so the sealed jars keep in the cupboard. Follow the quantities and times exactly.

French beans, not runner beans

The recipe was tested with fresh, tender green or yellow beans, which is exactly what French beans are. Runner beans are a different plant, with wider, fleshier pods, and weren't part of that testing, so this recipe doesn't cover them: freeze a runner bean glut instead, as the freezing and blanching guide explains. French beans are ready at 15–20 cm, when they snap cleanly. Keep picking every 2–3 days: a pod left to mature stops the plant producing more. For beans you can't pickle, see dealing with a glut of runner and French beans.

The beans go into the jars raw. Don't blanch or cook them first. Pack the pods whole, cut to length and standing upright, rather than sliced or chopped: the processing time is set for whole lengths packed this way.

Why the vinegar matters

Beans, like almost every fresh vegetable, are a low-acid food. Low-acid foods sit above pH 4.6, and at that level the bacteria that cause botulism can grow in a sealed jar. Plain beans can only be bottled safely in a pressure canner. The vinegar changes that: it brings the whole jar down to pH 4.6 or lower, acidic enough to block those bacteria, as long as the acid reaches every part of the jar evenly.

So the rules are strict:

• Use vinegar of 5% acidity, and check the label. Never use a vinegar of unknown strength.
• Never reduce the vinegar, add more water or pack in extra beans. The balance of vinegar, water and beans is the safety margin.

Processing the jars

Use jars of about 500 ml with new lids. The processing time is for jars of that size, so don't use it for smaller or larger jars. For choosing jars and lids, see jars for preserving.

Because the bath is so short, it doesn't sterilise the jars. That's why they must be sterilised before filling.

The jars go into a boiling-water canner: a deep pan with a rack in the bottom and a lid, deep enough for at least 2.5 cm of boiling water over the jar tops.

1. Put the rack in the pan, fill it about half full and heat the water to about 60°C (hot, but well short of simmering) before the filled jars go in.
2. Lower the jars in one at a time with a jar lifter, keeping them upright.
3. Top up with boiling water until the jars are covered by at least 2.5 cm. Pour it around the jars, not onto them.
4. Bring to a vigorous boil, cover, and start timing only once it is boiling.
5. Keep a steady, complete boil. If it stops boiling at any point, bring it back to the boil and start the timing again from zero.

Water boils at a lower temperature the higher up you are, which is why the time doubles above 305 m. Most kitchens need the 5 minutes, but in an upland village check your height above sea level first.

When the time is up, turn off the heat, take the lid off the pan and wait 5 minutes. Lift the jars out upright and stand them 2.5 cm apart on a towel or cooling rack. Leave them untouched for 12–24 hours.

Checking the seal

When the jars are cold, check each lid. On two-piece metal lids, the centre should curve down slightly and should not spring back when pressed. A dull sound when tapped with a teaspoon means no seal; a sealed lid gives a clear ring. For clip-top jars and other lid types, check the seal as the maker directs.

A jar that hasn't sealed goes in the fridge, to be eaten within a week.

If you skip the boiling-water step

Filling the jars with hot brine, putting the lids on and leaving them to cool doesn't make this pickle safe to keep in the cupboard. Treat those jars like jars that failed to seal: keep them in the fridge and eat them within a week.

Storing the jars

Take the screw bands off sealed jars, since a broken seal is easier to spot without them. Label the jars with the date and keep them somewhere clean, cool, dark and dry, ideally 10–21°C. Keep them away from hot pipes, the cooker, the boiler and sunlight, and never above 35°C. An unheated shed or garage is a poor store: damp can corrode lids and break the seal, and jars that freeze can soften, with spoilage getting in if a seal breaks. Make no more than you will eat within a year; how long preserves keep sets that against jams and chutneys.

Before opening a jar, look at it. Throw it out without tasting if:

• the lid has lost its seal
• there are streaks of dried food down from the top of the jar, rising bubbles or an unnatural colour
• it smells wrong, liquid spurts out when opened, or there is any mould

Once opened, keep the jar in the fridge and check it for the same signs each time.

Not the sweet mustard kind

Many British recipes for pickled beans, often made with runner beans, are a sweet, mustardy preserve of sliced beans thickened with cornflour and spiced with curry powder. Those recipes haven't been through the same safety testing, so the times and keeping advice here don't carry over to them. For another vinegar pickle made to a tested recipe, try pickled beetroot.

Common questions

Sources