Fondant is a sugar paste (sugar, water, corn syrup, gelatin) distinct from icing (powdered sugar, butter/liquid, flavorings). Understanding fondant’s composition, crystal structure, and properties explains why it creates smooth finishes but different texture than icing.
Fondant Composition & Ingredients
Fondant is a cooked sugar paste made by: (1) Cooking sugar, water, and corn syrup to soft-ball stage (~112-115°C). (2) Beating while cooling to create many tiny sugar crystals (desired crystal size ~0.5mm). (3) Adding gelatin, butter, and flavorings. (4) Kneading into smooth paste.
The result is a stiff paste with high sugar content (~85%), small water content (~15%), held together by fine sugar crystals suspended in sugar syrup. The paste can be rolled thin and draped over cakes, creating smooth, glossy finish.
Royal Icing Composition
Royal icing (confectioner’s sugar/powdered sugar, egg white or meringue powder, water) is fundamentally different: powdered sugar is finely ground sugar crystals mixed with starch. Royal icing mixes powdered sugar with liquid, creating thick liquid (not paste). The mixture is piped onto cakes, where it dries/sets through starch absorption and sugar crystallization.
Royal icing has higher water content than fondant and is more spreadable/pourable initially, setting firm as it dries. Fondant is already a stiff paste pre-application.
Sugar Crystal Structure
Fondant’s smooth texture results from extremely small sugar crystals (0.5-1mm). These tiny crystals feel smooth on the tongue—the small size means they don’t create grainy texture. Royal icing contains larger crystals and starch particles, creating grainier texture.
The crystal size is controlled during fondant preparation—beating while cooling creates many nucleation sites, resulting in many small crystals. Larger crystals would create grainy texture; tiny crystals create smooth texture.
Texture & Mouthfeel Differences
Fondant: Smooth, silky texture. Slightly chewy. Sweetness is intense and immediate. Royal icing: Harder, more brittle. Slightly grainy. Sweetness develops as it dissolves. Creamy texture if made with butter (buttercream icing).
Many people dislike fondant’s texture (too sweet, too chewy, artificial mouthfeel). Royal icing is preferred by many for its crispness and less overwhelming sweetness. The texture preference is subjective.
Fondant Preparation & Use
Store-bought fondant is ready to use. Homemade fondant must be: (1) Cooked to proper temperature. (2) Beaten while cooling to create crystals. (3) Kneaded until smooth. (4) Stored wrapped (prevents drying). To use: warm gently, knead to desired consistency, color with gel coloring, roll out, and drape over cake.
The process requires technique—proper beating creates smooth fondant; inadequate beating results in grainy texture. This is why many bakers purchase ready-made fondant rather than making it.
Why Icing Is Different
Icing encompasses multiple types: (1) Royal icing: Powdered sugar, egg white/meringue powder, water. Sets hard. (2) Buttercream: Butter, powdered sugar, flavorings. Creamy, softer. (3) Cream cheese frosting: Cream cheese, butter, powdered sugar. Tangy, creamy. All are technically “icings” because they’re spread/piped onto cakes, not paste that wraps them.
Fondant is categorically different—it’s a sugar paste that creates a smooth shell, not a frosting spread onto cake. The distinction reflects composition and application method rather than just semantics.
Appropriate Uses for Each
Fondant: Creating smooth, professional-looking cakes (wedding/special occasion). Covering entire cake surface. Creating precise decorations. Doesn’t taste great—flavor is secondary. Royal icing: Detail piping (borders, fine lines). Cookies. Small decorations. Better flavor. Buttercream: Most cakes. Frosting, piping, decorating. Great flavor. Preferred by many.
The choice depends on desired look and taste preferences. Professional bakeries often use fondant for appearance; home bakers often prefer buttercream for simplicity and flavor.