1. Quarter the tomatoes, place them in a preserving pan with the salt and vinegar, and simmer until they are soft and quite broken up.
2. Rub the mixture through coarse muslin or a fine nylon sieve; then return it to the pan and add the sugar.
3. Simmer until the ketchup starts to thicken, and then add the spices to taste, a little at a time, stirring thoroughly.
4. Meanwhile, heat enough bottles to hold the ketchup, and prepare seal, a boiled cork to fit the bottle and either waxed or covered with greaseproof paper tied securely over.
5. When the ketchup is thick enough, fill the hot bottles, leaving a head-space.
6. Seal immediately, or allow the ketchup to cool slightly; then fill up the bottles, leaving a headspace, and sterilize at 88°C for 30 minutes.
7. Seal immediately. Label when cold.
Note Remember that the ketchup will be thicker when cold, so do not reduce it too much.
To sterilise bottles see
Sterilising Bottles.