If your strawberry box has a few moldy ones, discard them; do not throw away the entire box of strawberries. With a paring knife remove the watery patches from the overripe ones before cooking them.
It is possible to reduce sugar in this recipe, but no more than 1/4 of the whole, because the preserves will be runny and not balanced. If you choose to alter the amount of sugar, you should add 1 grated Granny Smith apple, which is high in pectin, directly into the strawberry-sugar mixture while boiling.
Jars sterilisation process
You should make sure that your jars are clean to maintain the freshness of the preserves. Sterilise your jars by washing them (and their lids) thoroughly in hot soapy water. Rinse them well. Heat oven to 100°C. Place the jars and their lids on a baking sheet and put them in the oven for 20'. Using a funnel, ladle the preserves into the hot jars, filling to just below the rim. It is important that the jam is still hot when filling the jars. Cover with a lid. Immediately flip the jar upside down. Leave to cool completely. When cool it creates a suction that pulls the lid down. When you open the lid, you can hear a pop. The jam can be stored for up to 1 year (it will be long gone before that!) in a cool dry place. Refrigerate after opening.
How can I achieve a bright red colour for my strawberry preserves without adding artificial colour to it?
- Use white sugar.
- Do not use overripe strawberries.
- Bring the fruit mixture to a rapid, rolling boil over medium-high heat. Cook for 25'.