Why Unlined Copper Is the Secret to Better Jam
Copper is a metal that is highly reactive to changes in temperature. That’s why chefs love it – it heats quickly, spreads that heat evenly, and stops heating the instant you reduce the temperature or take a pan off the hob. Precision, precision, precision.
But copper doesn’t just react to heat – it also reacts with acidic ingredients in food, affecting the way it tastes. That’s why most copper cookware comes lined with stainless steel or tin, metals that will not react with ingredients.
The exception? Copper cookware that is used for confectionery, such as a copper jam pan. Here, sugar acts as a natural buffer, preventing the copper from reacting to the acidity of fruit.
Now you may be thinking: Why bother, if I could just make jam in a lined copper pan?
The answer is that you could, yes. But any professional or passionate jam maker can attest that an unlined copper jam pan – a pan completely uninhibited with a layer of stainless steel or tin that would slow it down – makes the silkiest, brightest, most flavourful jam, one that honours the peak-season flavours of whatever fruit you want to preserve. It’s an ‘if you know, you know’ kind of tool that is well worth the specialty gear.
Made by hand in Normandy since 1830, Mauviel copper jam pans are the gold standard for preserving – especially the traditional Mauviel M'Passion Hammered Copper Jam Pan with Bronze Handles.
Note: Copper jam pans are not compatible with induction hobs.
But copper doesn’t just react to heat – it also reacts with acidic ingredients in food, affecting the way it tastes. That’s why most copper cookware comes lined with stainless steel or tin, metals that will not react with ingredients.
The exception? Copper cookware that is used for confectionery, such as a copper jam pan. Here, sugar acts as a natural buffer, preventing the copper from reacting to the acidity of fruit.
Now you may be thinking: Why bother, if I could just make jam in a lined copper pan?
The answer is that you could, yes. But any professional or passionate jam maker can attest that an unlined copper jam pan – a pan completely uninhibited with a layer of stainless steel or tin that would slow it down – makes the silkiest, brightest, most flavourful jam, one that honours the peak-season flavours of whatever fruit you want to preserve. It’s an ‘if you know, you know’ kind of tool that is well worth the specialty gear.
Made by hand in Normandy since 1830, Mauviel copper jam pans are the gold standard for preserving – especially the traditional Mauviel M'Passion Hammered Copper Jam Pan with Bronze Handles.
Note: Copper jam pans are not compatible with induction hobs.
Why Copper and Jam Are So Compatible
Copper is an extraordinary conductor of heat, second only to silver. Because it is unfettered by a lining of stainless steel or tin, the metal responds instantly and evenly to your hob.
In jam making, speed and surface area are everything. The wide, flared sides of Mauviel jam pans encourage rapid evaporation, while the copper's conductivity ensures the mixture reaches the setting point much faster than in a standard pot. Copper is roughly 25 times more conductive than stainless steel, allowing your jam to reach the setting point in nearly half the time. This rapid heat transfer reduces the chance of the fruit’s natural pectin being overcooked, locking in vibrant colours and intense peak-season flavours before the heat has a chance to dull them.
In jam making, speed and surface area are everything. The wide, flared sides of Mauviel jam pans encourage rapid evaporation, while the copper's conductivity ensures the mixture reaches the setting point much faster than in a standard pot. Copper is roughly 25 times more conductive than stainless steel, allowing your jam to reach the setting point in nearly half the time. This rapid heat transfer reduces the chance of the fruit’s natural pectin being overcooked, locking in vibrant colours and intense peak-season flavours before the heat has a chance to dull them.
Why Are Mauviel Jam Pans Unique?
Mauviel copper jam pans use thick, professional-gauge copper that’s at least 1mm-thick. They have been made the same way for over a century, with function (rather than decoration or cutting corners) in mind.
Why does this matter? Thin copper can warp under the high temperatures required for sugar work, creating hot spots where jam can catch and burn. Mauviel’s thickness ensures the heat is distributed with total uniformity. Additionally, with the Mauviel hammered copper jam pan, the finish isn't just for looks – the martelage (hammering) process hardens the copper, making the pan more rigid and durable. It also masks wear-and-tear better, giving it a more intentionally rustic aesthetic.
Why does this matter? Thin copper can warp under the high temperatures required for sugar work, creating hot spots where jam can catch and burn. Mauviel’s thickness ensures the heat is distributed with total uniformity. Additionally, with the Mauviel hammered copper jam pan, the finish isn't just for looks – the martelage (hammering) process hardens the copper, making the pan more rigid and durable. It also masks wear-and-tear better, giving it a more intentionally rustic aesthetic.
Is an Unlined Copper Jam Pan Safe?
While copper can react with acidic foods, it is perfectly safe for jam making due to the high sugar content. The sugar effectively prevents the fruit's acid from reacting with the metal, ensuring no metallic taste is transferred to your preserves.
However, because it is unlined, this pan is specifically designed for high-sugar preparations like jams, jellies, and preserves. It should not be used for savory cooking or low-sugar sauces. Always follow these tips when using a copper jam pan:
However, because it is unlined, this pan is specifically designed for high-sugar preparations like jams, jellies, and preserves. It should not be used for savory cooking or low-sugar sauces. Always follow these tips when using a copper jam pan:
- Do not cook fruit (or any other ingredient) in the pan without sugar – always mix the fruit and sugar first before adding it to the pan.
- Make sure your recipe uses at least 50% of the fruit’s weight in sugar.
- Do not use a copper jam pan to macerate the fruit – instead, you can use a different container and transfer it to the jam pan when cooking.
How to Clean a Copper Jam Pan
Caring for a copper pan is not as fussy as you might think (especially since copper has naturally antimicrobial properties). It must be washed thoroughly after cooking, and given a polish to keep it shining. Follow these tips:- Hand Wash Only: Never put your copper pan in the dishwasher. The harsh chemicals in dishwasher detergents are far too aggressive for the metal and will dull the finish instantly.
- No Abrasive Scrubbers: After use, simply soak the pan in warm, soapy water to loosen any sugar residue. Use a soft sponge or cloth to wipe it clean. Avoid abrasive scouring pads, steel wool, or harsh chemicals, which can scratch the soft, hand-hammered surface.
- Dry Immediately: This is the most important step for preventing water spots and verdigris (a greenish oxidation). Use a soft, clean towel to dry the pan thoroughly as soon as you’ve finished washing it.
- Restore the Glow: Over time, copper naturally develops a deep, dark patina, a look that’s part of its rustic charm. However, if you love the bright, sun-like shine of a new pan – or feel like your pan is leaning a bit too ‘rustic’ – it’s time to bring out the Mauviel Copperbrill. This specialised paste is designed to restore original lustre in seconds, without the need for intense scrubbing. Simply apply with the soft sponge that’s included in every container, rinse, and dry for a showroom-ready finish.
What Else Is a Copper Jam Pan For?
In terms of cooking, a copper jam pan should only really be used for jam. However, it just so happens to make an elegant Champagne and wine bucket. If using it for this purpose, just make sure to follow the cleaning instructions above after use – a copper jam pan will need a restorative Copperbrill polish after prolonged contact with water.A Mauviel jam pan – especially the Mauviel M'Passion Hammered Copper Jam Pan with Bronze Handles – is a stunning piece of kitchen craft. It is a beautiful display piece for a kitchen shelf or hanging rack when not in use.
