Bottled tomatoes

Prepare the tomatoes:

Rinse the tomatoes well in clean water.
With a sharp knife, cut a small "X" on the bottom of each tomato with a knife.
Dip the tomatoes in boiling water until the skins start to split.
Carefully transfer the tomatoes into a colander and rinse under a cold tap until cool enough to handle.
Peel off the loose skins, remove any obvious hard cores - but leave the tomatoes whole if you can. Some heritage varieties might need a bit of trimming.

Pack the Jars:

Wash your glass jars and lids in hot, soapy water. Rinse and dry in the oven (preheated to 100ﹾC.
Add bottled lemon juice to each jar to ensure a safe pH (½ tablespoon for each 400ml jar
Pack the prepared tomatoes tightly into the jars, pressing down gently to release their natural juices and eliminate air pockets, leaving ½ inch of headspace at the top.
Wipe the jar rims clean with a damp cloth, and screw on the lids

Process in a Water Bath:

Use a stock pot (or similar) with a trivet or folded tea towel in the bottom to protect the glass from excessive heat. Place the filled jars on to the trivet and fill with water to immerse the jars by at least an inch
Bring the water 88ﹾC and maintain for cover the pot, and process pint jars for 40 minutes Adjust accordingly for larger jars. If you have a digital probe type thermometer, it’s worth checking the core temperature by lifting a jar out of the bath, unscrewing lid and probing the middle of the jar. Lid and return to the water bath for ten minutes. You’re looking for a core temperature of 70ﹾfor at least two minutes.
Turn off the heat and let the jars sit undisturbed in the hot water for 5 minutes before removing them.
Check the lids are slightly domed and sealed.
Set the hot jars on a towel and let them cool completely for 24 hours. Check that the centre of the lid is concave and does not flex when pressed to confirm a tight seal.
When you come to use them, check that the lids are still concave and that the lid is still sealed. If in doubt, bin them.