Science of Candy: What's Special About Fudge? | Exploratorium (2024)

What’s special about fudge?

Science of Candy: What's Special About Fudge? | Exploratorium (1) Fudge is one of the rare exceptions to the rule that sugar crystals are not desirable in candy. Tiny microcrystals in fudge are what give it its firm texture. The crystals are small enough, however, that they don’t feel grainy on your tongue, but smooth.

While you ultimately want crystals to form, it's important that they don't form too early. The key to successful, nongrainy fudge is in the cooling, not the cooking. The recipe calls for heating the ingredients to the soft-ball stage, or 234° F, then allowing it to cool undisturbed to approximately 110° F. If you stir during this cooling phase, you increase the likelihood that seed crystals will form too soon.

Science of Candy: What's Special About Fudge? | Exploratorium (2) A seed crystal is a surface that sucrose molecules (that's the sugar) can begin to attach themselves to—it could be a few sucrose molecules stuck together, a piece of dust, or even a little air bubble. Once a seed crystal forms, it grows bigger and bigger as the fudge cools. A lot of big crystals in fudge makes it grainy.

By letting the fudge cool without stirring, you avoid creating seed crystals. Stirring would help sucrose molecules "find" one another and start forming crystals. Stirring also introduces air, dust, and small dried bits from the walls of the saucepan—all potential seeds for crystal formation.

When the fudge has cooled to about 110° F, you want to start the crystallization process. You start to stir, and keep stirring, until the candy becomes thick. The more you stir, the more crystal seeds you get. But instead of getting a few huge crystals (and grainy candy), you get lots and lots of tiny crystals, which make for thick, smooth candy.

There are two other candies that deliberately employ sugar crystals. One is fondant, a wetter version of fudge that you find inside soft-center chocolates. The other is rock candy, for which a sugar solution is left for days to form enormous crystals.

Think you get it? Try making fudge or rock candy yourself!

Science of Candy: What's Special About Fudge? | Exploratorium (2024)

FAQs

Science of Candy: What's Special About Fudge? | Exploratorium? ›

Fudge is one of the rare exceptions to the rule that sugar crystals are not desirable in candy. Tiny microcrystals in fudge are what give it its firm texture. The crystals are small enough, however, that they don't feel grainy on your tongue, but smooth.

What is the science behind making fudge? ›

Cooking is necessary to dissolve sugar crystals and to evaporate part of the water in the cream. The length of this step has a direct impact on the firmness of the fudge. As water gradually evaporates, sugar is concentrated and the temperature of the mixture rises above 100°C (212°F).

What is the secret to good fudge? ›

You have to control two temperatures to make successful fudge: the cooking temperature AND the temperature at which the mixture cools before stirring to make it crystallize. Confectionery experiments have shown that the ideal cooking temperature for fudge is around 114 to 115 °C (237 to 239 °F).

How does fudge relate to chemistry? ›

The Science of Fudge: How Fudge Is Made

Fudge is made by heating sugar and water to a temperature above the boiling point for water, which is 212° Fahrenheit. The candy maker pours the syrup into a pan so it can cool faster. This technique helps prevent sucrose molecules from forming into a large crystal.

What are the characteristics of fudge? ›

Characterised by its smooth, creamy texture and decadent flavour, fudge is typically made from a mixture of sugar, butter, and milk or cream. The ingredients are heated to the soft-ball stage, around 235-245°F (113-118°C), and then beaten while cooling, which gives fudge its characteristic smooth and dense texture.

What makes fudge different? ›

Although fudge often contains chocolate, fudge is not the same as chocolate. Chocolate is a mix of cocoa solids, cocoa butter and sometimes sugar and other flavorings and is hard and brittle. Fudge is a mixture of sugar, dairy and flavorings that is cooked and cooled to form a smooth, semi-soft confection.

What makes fudge hard or soft? ›

The amount of time you cook fudge directly affects its firmness. Too little time and the water won't evaporate, causing the fudge to be soft. Conversely, cook it too long and fudge won't contain enough water, making it hard with a dry, crumbly texture.

How do you describe high quality fudge? ›

High-quality fudge tastes smooth and creamy because it contains small sugar crystals. It has a deep brown color and a satiny sheen. Poor-quality fudge tastes grainy because it contains large sugar crystals.

Why is fudge so good? ›

Between its deeply rich flavor and its silky texture, fudge makes a brilliant treat to pair with coffee. The sweet and bitter flavors complement one another perfectly, making for an unstoppable combination.

What makes fudge chewy? ›

Chewy fudge results from the excessive moisture present in the mixture, which means the fudge was not cooked to the right temperature and could not be cooked enough to release the moisture. However, take care not to overcook fudge because it will take away the moisture and leave you with hard, chewy candy.

Is making fudge considered baking? ›

Fudge is always a no-bake dessert and can be completely stove- and oven-free if you follow our method for how to make microwave fudge. That means it's a chocolate dessert idea that will keep your oven cool on even the steamiest days of summer.

What is the softball test when making fudge? ›

making of fudge

termed in kitchen parlance the soft ball stage, that point between 234 and 240 °F (112 and 115 °C) at which a small ball of the candy dropped in ice water neither disintegrates nor flattens when picked up with the fingers.

What are the interfering agents in fudge? ›

Corn syrup acts as an "interfering agent" in this and many other candy recipes. It contains long chains of glucose molecules that tend to keep the sucrose molecules in the candy syrup from crystallizing.

What makes high quality fudge? ›

Candy that isn't cooked long enough will end up too soft; overcooking makes fudge crumbly or hard. High-quality fudge has many small crystals. If the process of crystallization begins too early, fewer crystals form and they become much larger.

Top Articles
Latest Posts
Article information

Author: Rueben Jacobs

Last Updated:

Views: 5664

Rating: 4.7 / 5 (57 voted)

Reviews: 80% of readers found this page helpful

Author information

Name: Rueben Jacobs

Birthday: 1999-03-14

Address: 951 Caterina Walk, Schambergerside, CA 67667-0896

Phone: +6881806848632

Job: Internal Education Planner

Hobby: Candle making, Cabaret, Poi, Gambling, Rock climbing, Wood carving, Computer programming

Introduction: My name is Rueben Jacobs, I am a cooperative, beautiful, kind, comfortable, glamorous, open, magnificent person who loves writing and wants to share my knowledge and understanding with you.