METHOD:

1. Gently wash strawberries and hull. Place on paper towel or tea towel to remove excess water. Cut any large strawberries in half or quarters depending upon their size. 

2. Place the fruit in a preserving pan or a large heavy bottom large saucepan with a wide base. Add the sugar and the zest and strained lemon juice. 

3. Place the pan on medium heat. Using a wooden spoon, stir constantly and heat slowly until all the sugar has dissolved. Do not allow the mixture to boil until the sugar has completely dissolved.

4. Boil rapidly until set approximately 10-20 minutes. Use the flake test or sugar thermometer to test the set. When the jam has reached the setting point, take it off the heat. 

5. Skim any foam (scum)  from the surface with a metal spoon and discard. Allow the jam to cool slightly, approximately 10-15 minutes, to ensure the fruit is evenly distributed. 

6. Use a funnel and ladle to pour into warm dry sterilised screw cap sealable bottles. Fill to approximately 2.5cm (I inch) from the top of the bottle and seal using your preferred method.

7. Seal, label and store in a cool dark place in the kitchen or pantry.

   Allow the jam to mature for at least 2 weeks before eating

NOTES:

•  Choose ripe clean fruit. Do not use overripe and never use mouldy fruit as this will produce a poor quality jam. 
• Strawberries are low in pectin and acid. The addition of lemon juice is critical to obtain a good set. My post on what makes jam set  explains this in more detail. 
• The size of the fruit  will affect the cooking time and texture. Strawberries are a soft fruit, if you slice into small pieces the fruit will disintegrate during the cooking and produce a mushy jam texture. If you would prefer a jam with larger pieces, leave small strawberries whole and cut larger fruit in half or quarters.  
• Heat gently and cook slowly until the sugar has completely dissolved before boiling otherwise the fruit skins will toughen and the sugar will crystallise. 
• Once the sugar has dissolved and the fruit is soft, boil rapidly until the jam reaches its setting point.
• Stir occasionally to prevent the jam from sticking on the bottom of the pot. But not too often as this will lower the temperature and delays reaching the setting point. 
• Rapid boiling until the setting point is reached point helps to preserve the fresh citrus flavour. Long slow simmering of the jam affects the colour and reduce the flavour of the jam.
• An additional step to prevent mould forming during the storage, is to  cover with warm paraffin wax while the jam is hot.  Allow jam to cool completely and seal with screw top lid or cellophane paper. 
• If for some reason, a jam doesn’t set don’t discard it. It can be used as a delicious sauce to accompany cake, dessert or spooned lovingly over ice-cream. This jam does not contain a lot of liquid so should set quickly.
• Removing the scum
  • Jam, jellies, and marmalades can produce a scum while they are boiling. Impurities from the fruit and sugar will rise to the surface and a fine frothy foam will move towards the edge of the preserving pan. Some fruits will produce more scum that others.
  • This is a natural self-clarification process and makes the task of making a high-quality preserve make easier.
  • Removing the scum increases the  preserve’s clarity. This is very important if it is being submitted for competition. Remove the scum before bottling. Using a stainless-steel spoon, skim the scum from around the edge of the preserving pan. Be careful to remove just the scum and not the jam. This can be done while the jam is boiling and/or once it has been taken off the heat. Do not attempt to remove the scum from the centre of the boiling jam, as there is a high risk the jam with splutter and hot jam burns. 
  • Some preservers add a small knob on butter (25g per 900g fruit) to the fruit mixture after the sugar has been added. This helps to prevent the formation of scum.
• Using paraffin Wax
  • Paraffin wax is available in speciality preserving stores and some rural hardware stores.
  • The melted wax must be poured over the preserve while it is hot. 
  • Break the wax into small pieces and heat in a bowl set over a pan of hot water. Bring to the boil, reduce the heat to maintain a gentle simmer until the wax is just melted
  • Do not overheat. If it gets too hot it will shrink away from the sides of the  preserving jar as it cools. This will break the seal and allow impurities to access the contents, encouraging mould growth. 
  • Working quickly pour a thin layer over the hot preserve. Using a small wooden cocktail stick, toothpick, or cake skewer, prick any air bubbles. 
  • Allow the wax to set. Then pour a second thin layer to make a seal approximately 3mm thick. 
  • When the wax has set it will become opaque and dip slightly in the middle.
  • To use the preserve, break the wax seal and remove. 
  • Cover the jar with clear film and store in the fridge. 
  • Sealing with wax is not a long-term solution. Use within a couple of months.
• Variations. Strawberry, Grand Marnier and Cracked Pepper. Add  2 tablespoons Grand Marnier and 1/4 teaspoon freshly ground black pepper part way through boiling process. Take care when adding the Grand Marnier as it cause the hot jam to spurt.  The alcohol will boil off leaving a citrus undertone, adding a nice contrast to the pepper and fruitiness of the strawberries.