Why do people put simple syrup on their cake?

People put simple syrup on cakes for a variety of reasons. Simple syrup, also known as sugar syrup, is a mixture of sugar and water that is heated until the sugar dissolves. It results in a clear, thick, and sweet liquid that can be used to soak into cakes to add moisture and sweetness. Applying a simple syrup soak is a common technique used by bakers and pastry chefs for enhancing the texture and flavor of cakes. Let’s explore the main reasons why simple syrup is commonly used on cakes.

Keeps the cake moist and soft

One of the primary reasons for using simple syrup on cakes is to keep them moist and soft. The syrup permeates through the cake layers, preventing them from drying out. Cakes tend to dry out over time as the moisture escapes. A syrup soak provides additional moisture to the cake crumb, keeping it tender and fresh. The sugar in the syrup also retains moisture. This is especially useful for cakes that need to be refrigerated or set aside for some time before serving, such as wedding cakes or birthday cakes. The simple syrup keeps the cake from drying out in the fridge.

Enhances flavor

Simple syrup not only keeps a cake moist but also enhances its flavor. The syrup carries the sweetness deeper into the cake, resulting in a richer, more pronounced sweet taste. Cakes with a syrup soak tend to taste sweeter than those without. The syrup also blends with the existing flavors of the cake like chocolate, caramel, vanilla etc., allowing them to shine through better. For fruit-based cakes, a flavored syrup with fruit juices or extracts can provide a bright, refreshing taste.

Allows better absorption of other liquids

A cake soaked in simple syrup readily absorbs other liquids poured over it. Icings, frostings, sauces, and glazes that are poured over an untreated cake tend to slide right off. But on a cake treated with syrup, these liquids can permeate through the layers and set nicely. The syrup acts as a primer that enables better absorption. This gives a double benefit – moist interior and creamy exterior. Syrup-soaked cakes hold up well under juicy fillings too.

Provides texture contrast

Simple syrup provides an appealing contrast of textures – soft, moist interior and slightly sticky, chewy exterior. As the syrup soaks in, the outer layers of the cake absorb more liquid and become stickier, almost candied. The interior remains tender and moist. This variation in texture is part of what makes syrup-soaked cakes so enjoyable. The contrast is especially noticeable in dry cakes like sponge cake.

Prevents staleness

Left on its own, cake tends to become stale, dry and tough over time. This is due to staling, a process in baked goods by which the starch molecules retrograde and recrystallize. Simple syrup softens the starches in a cake and acts as a humectant, preventing recrystallization. This delays the staling process, keeping the cake tasting fresh for longer. For wedding cakes and other large cakes that need to remain fresh for days, soaking with simple syrup is almost mandatory.

Allows use of thicker frostings

On an unsoaked cake, a thick buttercream or ganache frosting may not adhere well or could cause the cake to become soggy. Simple syrup provides enough moisture within the cake layers to withstand a heavy, dense frosting on the exterior. The syrup works well with frostings like fudge frosting, cream cheese frosting, Italian meringue buttercream etc. It helps prevent a slippery mess and keeps the cake neatly frosted.

Seals in freshness

Drizzling hot simple syrup over a fresh baked cake creates a protective seal that locks in moisture and flavor. This prevents the cake from drying out during storage and transit. Simple syrup is sometimes brushed over just-baked pastries too for the same reason. The thin syrup layer ensures the cake stays fresh until it is time for filling and frosting. This technique works well for bakeries selling cakes.

Allows quicker assembly

Professional bakers often soak layered cakes with simple syrup before final assembly. This allows the syrup to evenly penetrate the layers while they are separate. Trying to brush syrup over an assembled cake risks uneven soakage and damage to the frosting. Pre-soaking the layers saves time and effort during busy cake assembly. Syrup can be quickly brushed on the layers which are then simply stacked and frosted.

Accentuates visual appeal

A glistening sheen from simple syrup on a cake can accentuate its visual appeal. Syrup adds a shiny glaze effect, especially if the cake is airbrushed with luster dust. Cakes for special occasions like weddings benefit from this extra touch of shimmer and radiance provided by a simple syrup soak. The syrup also improves the color vibrancy slightly.

Simplifies serving process

Syrup-treated cakes and pastries hold up better when cut and plated. The added moisture prevents crumbs and makes neat slices possible. It allows smooth serving of delicate cake types like genoise sponge, chiffon cake, and angel food cake that otherwise tend to tear or fragment easily. Simple syrup gives cakes a cohesive quality that retains the shape of servings.

Boosts visual height and volume

Brushing simple syrup on cake layers before stacking can boost their visual height and volume. The syrup causes a slight swelling as it hydrates the crumb. You can achieve a taller cake look with fewer layers. But excessive syrup can make layers unstable and slippery. Moderation is needed to get an optimal boost in height.

When to Use Simple Syrup on Cakes

Here are some common scenarios and cake types that benefit from the use of a simple syrup soak:

Very soft, tender cakes

Delicate cakes like chiffon cake, sponge cake, angel food cake, and fatless sponge cake have a very soft, feathery crumb that dries out easily. Using simple syrup preserves their tender texture.

Low-moisture, low-fat cakes

Cakes made without oil or butter, like vegan cakes, tend to be drier. Simple syrup compensates for the lack of natural fats and moisture.

Cakes filled and frosted with buttercream

Buttercream frosting leeches moisture from cake layers. Syrup prevents this moisture loss and provides enough sweetness to balance the rich frosting.

Refrigerated cakes

Simple syrup prevents refrigerated cakes and frozen ice cream cakes from drying out in the cold environment.

Cakes eaten over multiple days

For large occasion cakes meant to be enjoyed over an extended period, simple syrup helps maintain freshness between servings.

Cakes with fresh fruit

The syrup prevents fragile fruit fillings and toppings from causing the cake layers to become soggy.

Dry baked goods like pancakes and doughnuts

Simple syrup can be drizzled over pastries like pancakes, waffles, scones, and doughnuts to keep them moist and tasty.

Sponge cakes

Basic sponge cakes lack fat and need simple syrup to stay soft and moist. Genoise, biscuit, and honeycomb sponge cakes rely on syrup for moisture.


To prevent cupcakes from drying out once removed from the liner, bakers often brush syrup on the tops after baking.

Wedding cakes

Simple syrup is a must for keeping the cake layers in wedding cakes fresh until serving time. Fondant icing also blends better over syrup-saturated cake.

Bakery store-bought cakes

Syrup helps maintain the quality of cakes sold at bakeries during transport and shelf life.

How to Make Simple Syrup for Cakes

Here is a quick guide to preparing simple syrup at home for soaking cakes:


– 1 cup white granulated sugar
– 1 cup water
– Optional flavoring extracts, juices or zests


– Combine the sugar and water in a small saucepan.
– Heat on medium, stirring constantly, until the sugar dissolves.
– Once the syrup is clear, increase heat and bring to a boil.
– Let boil for 2 minutes without stirring.
– Remove from heat and add any optional flavorings.
– Allow to cool to room temperature before using.
– Store leftover syrup in the refrigerator.
– Reheat before use.


– Use a 1:1 ratio of sugar and water.
– Boiling concentrates the syrup slightly.
– Add extracts, juices or zests once syrup cools to prevent evaporating flavors.
– Take care not to burn or caramelize the syrup.
– Shake before use to remix any separated sugar.

Flavored Simple Syrup Ideas

– Vanilla
– Almond
– Lemon
– Orange
– Rose water
– Coffee
– Hazelnut
– Chocolate
– Coconut
– Mint
– Strawberry
– Lime
– Lavender

How to Apply Simple Syrup to Cake Layers

When saturating cake layers with simple syrup, here are some tips to follow:

Amount of syrup

– Thin layers: 1-2 Tbsp syrup
– Thick layers: 2-4 Tbsp syrup
– Sheet cakes: Around 5 Tbsp per 9×13 inch pan
– Avoid excess syrup that can make the cake soggy.

Application method

– Use a pastry brush to apply syrup evenly across layers.
– Or, drizzle syrup gently over layers.
– Poke holes with a fork so syrup absorbs better.
– Quickly flip over and brush other side too.
– Let layers sit briefly to fully absorb the syrup.

When to apply

– Apply after baking while cake is still warm so pores absorb syrup well.
– Can also apply cooled cake layers up to 24 hours before assembly.
– Avoid applying over frosted cakes as it may dissolve or ruin the frosting.

Pros and Cons of Using Simple Syrup on Cakes

Here is a look at some of the key advantages and potential drawbacks of soaking cakes with simple syrup:


– Keeps cakes moist and soft
– Allows cakes to stay fresh longer
– Enhances sweetness and flavor
– Provides tender, smooth texture
– Helps fruit fillings and frostings set better
– Prevents drying out during storage and refrigeration
– Adds decorative shine and luster


– Can make cakes too sweet if overused
– Creates moist, sticky layer on exterior
– Risks destabilizing cake layers if oversaturated
– Not ideal for dense cakes that already have enough moisture
– Requires an extra production step
– Excess amounts may ruin cake texture
– Some flavorings like rosewater can be overpowering

Frequently Asked Questions

Should simple syrup be hot or cold when applied?

Simple syrup can be used warm, at room temperature, or chilled. Warm syrup may absorb faster into a hot freshly baked cake. But room temperature or chilled syrup works well too.

Is simple syrup the same as soaking syrup?

Yes, simple syrup and soaking syrup refer to the same ingredient in cake making. It involves dissolving sugar in hot water to create a sweet liquid for moistening cakes.

Can I flavor simple syrup?

Yes, simple syrup can be infused with extracts, juices, herbs, spices, liqueurs, fruit purees, etc. Apply flavors once the syrup has boiled and cooled down.

Does simple syrup go bad?

Properly stored simple syrup keeps for 2-3 weeks refrigerated. Signs of spoilage are mold, fermentation bubbles, and off odors. Discard bad syrup.

What is saturated sugar syrup?

Saturated sugar syrup has more dissolved sugar than simple syrup. It contains equal weights of sugar and water for a very thick, viscous result.


While simple syrup may seem like an unnecessary step for home bakers, it provides undisputable benefits for flavor and texture of cakes. The modest effort of preparing and applying syrup is rewarded with moister cake layers, enhanced sweetness, preserved freshness, stable fillings and frostings, and prolonged shelf life. Syrup-soaked cakes simply taste better and hold up better. Mastering the use of simple syrup can elevate homemade and store-bought cakes to new heights.

Cake Type Recommended Amount of Simple Syrup
Sheet Cake (9×13 inches) 1/4 – 1/2 cup
Two Layer Round Cake (8 inches) 2-4 tablespoons per layer
Sponge Cake 1-2 tablespoons per layer
Cupcakes 1 teaspoon per cupcake
Pound Cake 2-3 tablespoons for entire cake
Wedding Cake 2-3 tablespoons per layer
Angel Food Cake 3-4 tablespoons for entire cake

Leave a Comment