Why Do Candy Makers Use Copper Pots?

For centuries, copper pots have been the cookware of choice for professional candy makers and confectioners. The use of these gleaming copper vessels persists today among both artisanal candy shops and large-scale manufacturers. But why has copper become so intrinsically linked with the creation of candy? As it turns out, there are some very practical reasons behind sugar makers’ affinity for copper pots.

Superior Thermal Conductivity

Copper‘s standout benefit is its unrivaled thermal conductivity. This refers to a material‘s ability to conduct heat effectively throughout its structure. Of all metals, copper has the highest thermal conductivity rating, measuring 401 W/mK (watts per meter per degree Kelvin). This is over 60% higher than the next closest metal, silver.

This high conductivity rapidly absorbs heat and distributes it evenly across the pan. According to food science research, a copper pan can heat up nearly twice as fast as stainless steel cookware. This enables remarkably precise temperature control during the candy making process.

As the sugar solution is heated in a copper pot, the heat spreads smoothly and uniformly across the bottom and sides of the vessel. There are no hot or cold spots. This allows the sugar to fully dissolve and caramelize at an even rate, preventing burning or crystallization. Frequent stirring helps maintain this consistent heating.

Candy making relies on bringing sugar mixtures to precise temperature stages as they boil. Copper’s excellent conductivity lets candy makers carefully raise the sugar to the needed temperature for the desired consistency, whether a chewy caramel at 235°F or a hard crack toffee reaching 300°F. This level of temperature control is much harder to achieve with pots made of materials like stainless steel or aluminum.

“Copper is our go-to for candy making because of how responsive it is to changes in stove temperature,” explains Lisa Wilson, head chef at Amy’s Candy Kitchen in Chicago. “We can fine-tune the heat, catching the sugar at just the right moment before it burns.”

Acid Resistance

Another useful property of copper is its resistance to corrosion from acidic ingredients like sugar. Most metals will react to some degree with acids, but copper holds up well against sugar’s acidity during the vigorous boiling of candy making. This minimizes potential off-tastes or chemical leaching from the cookware.

In a laboratory corrosion analysis, copper showed 2-3 times less material loss compared to common grades of stainless steel when exposed to a 40% sugar solution. And unlike metals such as aluminum and carbon steel, copper did not show pitting or surface defects from the acidic environment.

Aluminum, for example, can undergo pitting, oxidation, and other reactions when used to cook sugars and acids at high heat. This ruins the pan and risks metallic flavors in the candy. Copper’s unreactive nature avoids this problem. It also allows the pans to better withstand repeated washings and reuse.

Heat Retention

In addition to conducting heat rapidly, copper also retains heat effectively once hot. This heat retention ability enables the precise maintenance of temperatures when cooking candy. Even after the heat source is reduced or removed, copper holds onto enough residual heat to keep sugar mixtures from cooling down too quickly as they are worked.

With a specific heat capacity of 0.385 J/g°C, copper can store nearly twice as much heat energy compared to stainless steel (0.21 J/g°C). This thermal mass provides the right balance of responsiveness to temperature changes while maintaining enough heat throughout the process.

Candy making requires prolonged heating followed by short cooling periods as ingredients are added and batches shaped or poured. Copper’s thermal mass provides the right balance of responsiveness to temperature changes while maintaining enough heat throughout the process.

“Copper’s ability to hold its temperature makes it perfect for candy work,” says Janet Willis, owner of Sweet Things Candy Shop. “Even off the stove, copper gives me more time before candies start setting up.”

Cleanability

Copper’s smooth, non-porous surface makes it easy to keep pots and utensils clean and sanitary. Proper cleaning between batches helps prevent cross-contamination of flavors, colors, and ingredients in candy making. The dark patina that forms on copper over time also creates a protective barrier against surface adhesion.

Vigorous scrubbing easily removes any residual sugars or food residues from used copper pans. This allows candy makers to quickly prepare equipment for reuse in additional batches. Keeping copper pots well-maintained and lined can prevent buildup of oxidized metal that could potentially leach.

Major candy brands like Mars and Hershey utilize automated cleaning systems and food-grade detergents to efficiently sanitize their copper equipment. This rigorous sanitation allows them to safely produce massive, continuous batches of candy.

Aesthetic Appeal

In addition to its ideal thermal properties, copper brings a warmth, glow, and old-world charm to any candy kitchen. The striking beauty of gleaming copper pots evokes nostalgia and artisanship. Using classic copper kettles and pots helps continue long-standing candy making traditions.

Candy store displays often prominently feature rows of shiny copper pans, both for their visual appeal and to allow customers to watch the candy making process first-hand. The warm, reddish-orange tone of copper pots also nicely complements many candies’ colors and ingredients.

“Copper just looks right in a candy kitchen – its warm, vintage vibe blends perfectly with the craft of candy making,” says Michael Jones, designer and founder of Cherry Hill Confections. “Seeing those copper pots immediately tells customers they’re getting a quality, handmade product.”

Potential Health Concerns with Copper

While copper offers many benefits for candy production, there are also some potential health concerns to consider with its use in cooking. Copper can leach into acidic foods over prolonged contact, especially if the cookware is worn or damaged. Consuming high amounts of copper can cause nausea, vomiting, and diarrhea.

Certain populations are at greater risk of copper toxicity, including:

• Those with Wilson’s disease (30-100x more copper absorption)
• People with rare ATP7B gene mutations
• Young children under age 1

The risks from occasional candy consumption are low for most people, but those with copper regulation disorders should be especially cautious and limit intake of copper-cooked foods. Damaged cookware or improperly prepared pans can increase the chances of copper ingestion.

To enjoy sweets safely, candy makers must keep copper pans well-maintained through regular re-tinning every 1-2 years and careful handling to avoid dents and scratches. Only heating sugar mixtures to the minimum temps needed, avoiding over-boiling, and promptly removing batches from pans will also help minimize copper leaching.

Alternatives to Copper Pots

While copper reigns supreme for many professional candy makers, alternatives like stainless steel, tempered glass, and lined copper can still get the job done. Stainless steel provides great durability and ease of cleaning but lacks copper’s heat responsiveness. Glass allows visibility of the process but is less efficient at conducting heat.

Lined copper combines the traditional appearance with a stainless steel interior to prevent copper contact with food. While not offering quite the same level of temperature control, lined copper can provide a compromise for those concerned about potential leaching while still retaining some classic appeal.

“For home hobbyists, I’d recommend a high-quality lined copper pan,” says candy expert Alicia Thompson. “You’ll get gorgeous cookware that’s safer and lower maintenance than pure copper.”

Tips for Using Copper at Home

While professional-grade copper pots can be pricey, consumers can still purchase small artisanal copper pans to make candy at home. Here are some tips for using copper effectively as an amateur candy maker:

• Choose a pan with 2-3 mm thickness for the best conductivity and durability

• Handwash gently with non-abrasive cleaners to maintain the inner tinning

• Avoid cooking highly acidic ingredients like tomatoes or vinegar

• Use wood, silicone, or plastic utensils to stir and mix candy in the pans

• Store pans well-sealed and avoid humidity/salt air to prevent corrosion

• Limit candy batch sizes and heating times to reduce copper exposure

• Consider a stainless-lined copper pan if concerned about contact with the copper surface

The Takeaway

With its excellent thermal properties, corrosion resistance, retainment of heat, cleanability, and timeless appearance, it’s easy to see why copper remains the pot metal of choice for candy creation. Taking care to properly maintain the pots and following good manufacturing practices can help minimize risks of copper ingestion.

So next time you savor a piece of creamy fudge or snappy lollipop from your local candy shop, you can appreciate the critical role that copper pots play in crafting these delicious treats. The gleam of copper will likely continue sweetening candy kitchens for generations to come.