270 g unwaxed lemons plus 35 g salt, blended into a paste, give you the most long-lasting flavour base we know. The ratio is no accident: that much salt binds the water in the lemon so firmly that the mixture stays stable for months without any cooking, freezing, or preserving. The peel, flesh, and juice all go into the jar together, and that is precisely the point.
We started making this paste regularly a few years ago because lemons kept going mouldy in the fruit bowl. Now a jar lives permanently in the fridge, and 1 tsp of it replaces the juice and zest of half a lemon in everyday cooking. When a recipe calls for the zest of a lemon, we do not need to go to the shops first. We just open the screw-top jar.
Thermomix® Lemon Salt Paste
Ingredients 0 / 2 ✓
- 270 g lemons untreated
- 35 g Salt
Instructions 0 / 4
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1
Zitronen schneiden.
Wash lemons well with hot water, quarter, (remove seeds) and add to mixing bowl.
- 270 g lemons
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2
Zitronen zerkleinern.
Add the salt and grind for 5 seconds/step 5.
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3
Zitronen pürieren.
Push down with the spatula, mix for 10 seconds/level 8. Push everything down again and mix for another 10 seconds/level 8.
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4
Paste abfüllen.
Pour the paste in a sterilized canning jar and store in the refrigerator.
Tip: For a larger quantity of lemon paste, you can double the ingredients.
You can also prepare the paste with limes.
Video
Nutrition per serving
Why 35 g of salt to 270 g of lemon is the right ratio
Salt preserves not through magic but through water binding. The salt draws the water out of the flesh and peel, binds it osmotically, and removes the conditions bacteria and mould need to survive. At 35 g of salt to 270 g of lemon, the salt content in the finished jar is around 13 per cent, and that is exactly the threshold at which the paste stays stable for months.
We tried it with less salt because we wanted a milder paste. At 25 g of salt the mixture started to ferment after eight weeks and fizzed slightly when we opened the jar. That is a clear sign the preservation has failed. Since then we have stuck strictly to the ratio and balance the salt content in the finished dish by counting 1 tsp of paste as part of the seasoning and leaving out the extra pinch of salt.
The peel is essential, juice alone is not enough
The real flavour of a lemon is not in the juice but in the essential oils of the yellow peel. Limonene, citral, and a range of other aromatic compounds are stored there and are only released when the peel is broken down. Juice alone tastes only sour. The peel delivers what we normally call the lemon character. That is exactly why the lemons go into the Thermomix® mixing bowl with their peel on.
The condition for this is unwaxed organic lemons. Conventionally grown lemons are treated with waxes and fungicides to prevent spoiling during transport. This coating does not come off completely even under hot water, and it would go straight into the jar. We use only organic fruit, wash it under hot water, dry it briefly, then slice it and remove the pips.
Speed 5 chops, speed 8 blends
The Thermomix® handles the paste in two steps, and there is a reason for that. In the first step we put the lemon slices and salt into the mixing bowl for 5 seconds at speed 5. At this setting the pieces are roughly chopped, the salt is distributed, and immediately starts drawing water out of the flesh. If we went straight to speed 8, the peel would be chopped unevenly and some of it would stick to the sides of the bowl.
In the second step we push the mixture down with the spatula and blend for 10 seconds at speed 8. We repeat this once, because otherwise the peel still contains fibrous pieces. Only after the second pass is the paste fine enough to stir into a sauce later without lumps. The two-step approach is our most important lesson from more than twenty jars now: doing everything at once on a high speed produces an uneven mixture with stringy bits.
Sterilising is not a detail, it is decisive
We rinse the screw-top jar and lid with boiling water every single time before filling the paste in. This is not a ritual. It is the moment that determines shelf life. Even a jar fresh out of the dishwasher still has residual bacteria around the rim and in the thread. In the salty, slightly acidic environment of the lemon paste they multiply slowly, but eventually the jar goes off regardless.
Concretely, here is how we do it: bring water in the kettle to the boil, place the jar and lid in a heatproof bowl, pour the boiling water over them, leave for one minute, then pour the water away and leave the jar to drain upside down on a clean tea towel. Only once the inside of the jar looks dry again do we fill in the paste. With this method our paste reliably keeps for six months, sometimes longer.
What 1 tsp of paste actually replaces
For everyday cooking we work with a simple rule of thumb. One level teaspoon of lemon salt paste is roughly equivalent to the juice and zest of half an organic lemon plus a small pinch of salt. That is enough for a salad dressing for four servings, a marinade for fish, or the finishing touch in a tomato soup. In bakes such as lemon cake we use two tsp of paste instead of the zest of a whole lemon and reduce the amount of salt in the batter by one pinch. We taste after baking to check whether a splash of fresh lemon juice in the glaze is still needed.
When we want to stir the paste into a liquid, for example into a finished sauce or a dressing, we first loosen it with roughly the same amount of water. Added directly to hot liquid it can form small lumps because the salt dissolves unevenly. Pre-dissolved with a tablespoon of water, it spreads smoothly.
Where we actually use the paste
In everyday cooking the paste ends up mainly in savoury dishes. For the lemon garlic fish from the Varoma we stir 2 tsp of paste into the stock, which completely replaces the lemon slices on the fillet and means the flavour penetrates the fish flesh more evenly. In vinaigrettes, dips, and hummus we add 1 tsp of paste because it lets us control the salt level in the finished dish much more precisely than fresh juice plus salt separately.
In sweet recipes we use it more sparingly. For a classic lemon cake or a moist lemon sheet cake we mix the paste into the batter instead of the grated zest, subtract the amount of salt stated in the recipe, and taste briefly after baking to see whether a splash of fresh lemon juice in the glaze is still needed. For lemonades and syrups such as our lemon lemonade or lemon ginger syrup we stay with fresh lemons, because there the acidity plays the leading role rather than the peel.
Think of the paste the same way as garlic base paste
Anyone who knows our garlic base paste can think of the lemon salt paste in almost exactly the same way. There too, salt preserves the fresh ingredient. There too, 1 tsp of paste replaces a garlic clove plus a pinch of salt. There too, we sterilise the jar and always take out the paste with a clean spoon. If you keep both pastes in the fridge at the same time, you cover the bulk of the quick flavour base for sauces, dips, and marinades without needing fresh lemon and garlic on hand every time.
What can happen and what is not a problem
After a few weeks the paste often darkens slightly, shifting from bright yellow towards a muted ochre. This is completely normal oxidation of the essential oils and is not a sign of spoilage. The smell and taste remain stable. If the paste smells musty, a layer of mould appears on the surface, or the jar hisses when you open it, throw it away immediately. We have had this happen exactly once in over three years, and it was down to a jar we had not sterilised properly.
The second point is the spoon. Using a soup spoon straight from the bowl to dip into the jar brings micro-organisms from the dish into the paste every single time. We always use a freshly washed or clean spoon. That sounds pedantic, but it is the difference between six weeks and six months of shelf life.
Limes as a variation, not a replacement for juice
We occasionally make the paste with limes instead of lemons. The ratio stays the same: 270 g limes to 35 g salt. The paste comes out more intense and resinous in flavour because lime peel carries more bitter notes than lemon peel. We then use it specifically for Asian marinades or guacamole, not as a universal substitute. If you keep both versions in the fridge at the same time, label the jars clearly because after two weeks the colours are barely distinguishable.
What we have not tried, and do not recommend, are mixtures of lemon and lime in one jar. The flavour profiles overlap and end up producing a paste that does not quite fit anywhere. Better to keep two small jars in parallel than one large jar with mixed fruit.
Store in the fridge, not on the pantry shelf
Despite the high salt content, the paste belongs in the fridge, not in the kitchen cupboard. At room temperature the essential oils in the peel become unstable, the flavour drops off noticeably within a few weeks, and the mixture turns slightly bitter. At around 5 °C in the fridge the paste keeps reliably for half a year. Freezing is possible but has not caught on with us, because the paste keeps long enough in the fridge anyway and is ready to hand in the jar.
We always fill it right to the brim and smooth the surface with a clean spoon so that as little air as possible is in contact with the paste. A thin layer of good olive oil on top is optional and acts as an additional oxygen barrier. If you use the paste regularly you can skip that. If you open the jar only occasionally, the oil is worth adding.
More recipes with lemon can be found in our collection. We recommend the Varoma lemon garlic fish, the lemon peach cake, and the lemon layer dessert.
