It’s one of life’s greatest and simplest pleasures - a crunchy slice of thick cut toast with a brush of butter and a generous helping of rustic jam. And there’s no doubt about it, making your own jam from scratch not only brings about that special feeling of having created something for yourself, it’s also plenty more flavourful than the supermarket offerings. For the uninitiated, making your own preserves can seem like a daunting prospect – but this handy Schwartz guide will tell you everything you need to know about how to make jam, where and when to pick seasonal fruit, and how to store it afterwards.

Where and when to pick fruit

Many believe that you should wait until ripe fruit is dropping from the trees before you start cooking it up into jam. Indeed, the end of summer is the perfect time for saving that soft fruit from the garden, or even helping a neighbour clear their trees before the plums start raining on the pavement.

While jam is the perfect recipe for saving fruit, it is in fact slightly under-ripe produce which has just the right level of acidity for preserving. Fruit should be picked when dry, from a pick-your-own farm or even from your own garden. Of course, if you can’t pick your own, frozen fruits or shop-bought produce make for a good substitute.

In the early autumnal months, apples, blackberries, gooseberries, peaches, pears, plums, raspberries and strawberries are among the best produce you can get in season. You can find many guides to seasonable produce online.

Which types of fruit should I use?

Take your pick! You can use practically any fruit for your jam – just be aware that some fruits are naturally higher in pectin than others. Pectin is a naturally occurring jelling substance that’s found in all fruit and can aid the jam-making process. When choosing your fruit, it’s a good idea to use either high-pectin fruits or a combination of low- and high-pectin produce.

High-pectin fruits include cooking apples, plums, blackcurrants and cranberries.
Low-pectin fruits include most berries, rhubarb, dessert apples and sweet cherries.

Cooking apples can often be combined with a low-pectin fruit for an ideal jam consistency. If you want to make a jam out of just low-pectin fruit, such as strawberry, a squeeze of lemon juice or a small amount of jam sugar can be used to bring up the acidity levels.

Which spices should I add to my jam?

The great thing about jam is that you can tweak and tailor any recipe to create your very own variety. With just a little subtle spice, you can bring out the natural taste of the fruit and add a wonderful depth of flavour to your preserve. We love blueberry jam with star anise and nutmeg, plum with a hint of ginger, or apricot with a spicy touch of cinnamon – but the versatility of spice blends means the flavour combinations are literally endless!

One of our favourite fruit and spice combos is apple with a blend of chai flavours. Simply mix two parts cinnamon to one part crushed cardamom pods, add a little ginger and nutmeg and finish with a whole star anise.

How to make jam

Jam making is a surprisingly simple process – so simple, in fact, that it can be *boiled* down to just three simple steps:

1. Boil the fruit
Boil the fruit along with your selected spices in a saucepan until softened.

2. Heat the sugar
While the fruit is cooking, put the sugar in the oven on a medium heat for about 15 minutes, making sure it doesn’t start to caramelize. Heating the sugar before you add it to the fruit ensures that everything will cook together as quick as possible, so you can expect the freshest, deepest flavour from your jam. You should heat around ¼ cup of sugar for every 2 ½ cups of fruit, allowing for a little extra to taste.

3. Add the sugar
Make sure the fruit is nice and soft before adding the sugar, as it has a hardening effect on fruit. Keep tasting your jam to make sure you add the right amount - but be quick! The faster jam cooks, the better it tastes. Leave to boil for around 5-8 minutes.

How do I know when it’s done?

The best way to check whether your jam is ready is to put a small plate or a couple of metal spoons in the freezer before cooking. There are then two tests you can do.

Firstly, you can drizzle some jam on one of the spoons and leave to cool for a few seconds. Run a line through the jam with a finger – if it leaves a clean line without the jam running back into the centre, then the jam will set.

Alternatively, put a teaspoon of jam onto the plate and, once cooled, push the edge of the jam circle towards the centre. If the surface wrinkles at all, it’s done.

How to store jam?

Jam should be stored in jars that have been sterilised in boiling water and thoroughly dried. Cover immediately with either a jam cover or sterilised screw top. If you use a cellophane jam cover, moisten one side before securing in place so the cover is taut when the preserve cools.

There’s no need to store your homemade jam in the fridge. Simply store in a cool, dark place.

Jam recipes

We love fresh homemade jam on a simple slice of crusty bread - but you can pull out all the stops with these fantastic Schwartz recipes that go perfectly with jam.
• Toasted brioche loaf
• American raspberry pancakes
• Scones with strawberry and vanilla jam
• Rosemary smoked tomato jam on toast