Strawberry jam

Jam diaries #5: Strawberry

Strawberry jam is one of the simplest and, at the same time, the most difficult jam to make. Breaking down the fruit and mixing with sugar is easy. The setting point of this jam is near impossible to achieve. Strawberries have almost nil pectin so unless you mix it with apples, redcurrants or other pectin-rich fruits or add pectin to the jam, setting is not going to happen!

This year a friend ask me for advice to make her own strawberry jam. It was her first time. She didn't get a setting point and was worried. I told her not to worry, it's the flavour that matters! It is true however I did felt a bit guilty for maybe not have given her as much advice as I should when she asked me what sugar to use. Should I have advised jam sugar (sugar rich in pectin) that even Darina Allen admits using in her strawberry jam? I tried adding pectin to the jam a few years ago and got nowhere but maybe I wasn't using it right? The jam sugar container advises a 1:1 ratio and I didn't do this before: does it make a difference?

I decided to follow the footsteps of a friend who blew up his makeshift Lab in his parent's garage when he was a teenager and perform a scientific experiment. No bang! expected this time!

I decided to play with jam sugar (pectin-rich sugar) and made 3 different mixtures:

• 1:1 ratio (1kg strawberries to 1kg jam sugar)
• 1:½ ratio (1kg strawberries to ½kg jam sugar)
• my usual ratio as the control mixture of 1:½ (1kg strawberries to ½kg granulated sugar)

The cooking process was the same for all and it took exactly the same time.

The end result was far from the same: 

Serves: 400g.

Ingredients:

• 500g strawberries, hulled and halved
• 250g granulated sugar
• juice of ½ lemon

Method:

1. Put the strawberries and lemon juice in a stainless-steel pan and cover with the sugar. Leave overnight. I identified which mixture was which with different coloured clips. 

   

   How the mixtures looked like the morning after. In the mixture with the highest concentration of sugar (top right - black clip), the sugar didn't completely dissolve.

2. Bring the strawberries to the boil and stir until the sugar is dissolved and the strawberries are cooked through. This takes around 30 min.
   
   
   
3. Mash the berries with a masher or with a handheld blender. I use the blender as I like a smooth finish.
4. Continue to boil until it reaches a setting point, about 15 min.
5. Strawberry jam forms plenty of scum (froth) at the surface. I think that blending instead of mashing makes it even worst. An old trick to get rid of the scum is to add a tiny lump of butter into the jam, which will dissolve it. However, I don't like removing the 'vegan' label from the jam so I don't do this. Instead, I keep stirring the jam as it cooks and eventually the scum disappears. Hard work but worth it!
   
   
   
   
6. Fill into sterilised jars, and cover with tightly fitting lids. I do not use silicone or paper discs so I fill the jars all the way to the top. The less air inside, the less chances of mold developing. 
7. Store in a cool, dark place. 
   

How to sterilise jars and lids?

Jars: heat them in a 180°C oven for 10 min. Let them cool.

Lids: boil them in water for 10 min. Let them air dry upside down. If you are tight for time, let them dry on the door of the open oven once you've sterilised the jars and the oven if off.

What is a setting point?

Literature tells us that the jam setting point is reached at 105°C. I bought a sugar thermometer specially for this. I really cannot get my jams to get to 105°C so I quit on the thermometer!

There is an easier way, the wrinkle method, which involves a cold plate. Check this link out: https://www.cookingwithnanaling.com/how-to-tell-when-jam-is-set/

In time you won't need any of these methods. Experience of looking on how the jam sets on your stirring spoon will tell you when it's ready.

How long will the jam last for?

Literature tells you jams will last for 6 months and the more sugar you add to them the longer they will last as sugar is a preservative. Jams usually have a 1:1 fruit to sugar ratio to make them last longer.

Personally, that is not my experience. I usually use half the amount of sugar so a 1:½ fruit to sugar ratio. Some years we are eating jams 1 year later and they are still absolutely fine.

Perhaps the jam has developed a bit of mold on the top when you open it. Do not throw it away!!! Just scoop the mold out and continue eating. If you are a fast eater like my partner, you can store the jam in the cupboard. If you are not, store it in the fridge.