Homemade strawberry jam

My sweet science experiment

Before I get into this one, I have a confession to make… I’ve never been a fan of jam! Even though I’ve got a massive sweet tooth, I usually find shop-bought jam far too sugary. The only one I’ve ever really liked is Tiptree Strawberry Conserve - it tastes a bit less sweet and has a deeper, fruitier flavour.

In July, with strawberries in peak season here in the UK, I decided to try making my own jam. Inspired by the Tiptree version, I picked up some strawberries from Hugh Lowe Farms (thanks to Steve’s on Herbert Road for stocking them). Armed with my Thermomix and a bag of fruit, I was ready to experiment!

I found a simple, four-ingredient recipe on Cookidoo: strawberries, sugar, lemon juice, and coconut oil. Compared to Tiptree’s version, that’s just one less ingredient. Their conserve also includes citrus pectin (a gelling agent) and citric acid (an acidity regulator). After a quick bit of research, I learned that lemon juice naturally does both of those jobs - pretty cool!

The sugar shock - will my pancreas forgive me?

When I saw the amount of sugar required, I genuinely did a double take. 17-18 oz of sugar compared to 23 oz of fruit! I thought it was a mistake. Surely I could cut it down? But it turns out sugar isn’t just for sweetness - it’s crucial to achieving the right jammy consistency. Initially, I was disappointed… until I remembered: this is homemade. I can tweak things to suit my taste!

So I tried a mixture of golden caster sugar (my go-to) and coconut sugar, which I discovered a few years ago. I used a 1:2 ratio - one part coconut sugar to two parts caster sugar - and hoped for the best.

Quick side note: I used to think coconut sugar came from coconuts, but it’s actually made from the sap of coconut flower blossoms. It’s often marketed as having a lower glycemic index, though that claim is still up for debate (maybe a topic for another blog). Either way, I love its nutty flavour - it works beautifully in baking and I hoped it would help me get that deeper, Tiptree-style taste.

The transformation stage, aka “is it burnt?”

As the mixture bubbled away in the Thermomix, the smell of warm, sweet strawberries filled the kitchen. I was getting excited! But when the timer went off and I opened the lid, my husband and I both stared in shock: “It looks burnt,” he said.

My heart sank - until I remembered how dark the Tiptree jam is. I compared colours and realised it wasn’t burnt at all, just rich and deeply caramelised.

the sugar and strawberry mixture inside of the Thermomix before it is cooked, you can hardly see the strawberries under the large amount of sugar

the Thermomix with the base of the Varoma ontop, as the screen on the Thermomix instructs the user to do

the cooked mixture inside of the Thermomix, it looks reddish brown and gelatinous with bits of cooked strawberry spattered around the inside of the mixing bowl

The wrinkle test: when it’s ready, according to science!

Then came something I’d never heard of before: the wrinkle test. According to the recipe tips, you pop a saucer in the freezer for a few minutes, then smear a bit of jam on it. Push it with your finger - if it wrinkles, it’ll set. If not, cook it a few minutes longer and try again. Genius!

an intact dollop of cooked jam on a plate, with a halo of condensation around it

a finger pushed into the dollop of jam on the plate, squishing the mixture whereby faint crease marks on the top of the jam can be seen

Thanks to the recipe tips, I also learned how to sterilise jars (a first for me!). I reused some old Gü glass pots, gave them a hot soapy wash, and popped them into a 150°C oven for 15 minutes.

Then came the tricky part - carefully pouring hot jam into hot jars, trying not to spill or burn myself, and leaving a 3cm gap at the top. I couldn’t wait for it to cool, so I snuck a taste off a spoon - and wow. It was delicious! Just the right level of sweetness, with that lovely strawberry texture still intact.

I felt genuinely proud. It was like a fun little chemistry experiment - and cleanup was a breeze thanks to the Thermomix Pre-Clean mode. I used the “fats and caramel” option, added water, soap, and a splash of vinegar, and in 7 minutes the jug was sparkling again, hands-free.

on a wood table, two glass jars of homemade strawberry jam with gold lids, twine wrapped around the lips of the jars, and off white rectangular labels that say Homemade on the Hill strawberry jam.

Preserving the goodness and sharing the success

Since that first batch, I’ve made more jam - and even dressed up a couple of jars with twine and handmade labels to give to my first two customers. It felt so good to make something local, seasonal, and truly homemade.

I’m already thinking about what to make next in August. What star ingredient should I try next? Want to see more of what the Thermomix can do? Book a free cooking experience with me to see how it can help you create your own homemade gifts - and everyday meals - with ease.

This blog is part of the "When life gives you..." series in which I conduct Thermomix experiments with a star ingredient, inspired by what is in season at the time or produce I've come across that I would like to try.

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