The only surefire way to dry royal icing is simply time - letting royal icing cookies sit out at room temperature to fully harden. This typically takes a minimum of 6-8 hours. Though there is no substitute for time, there are a few tips and tricks to help speed up the process.
- Dry Royal Icing Cookies in Front of a Fan
- Use a Food Dehydrator to Dry Royal Icing
- Make a Thicker Consistency Icing for Quicker Drying Time
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What is Royal Icing?
Royal Icing is different from many other buttercream frostings or icings in that it dries hard with a smooth finish. This makes it ideal for making intricate and fun cookie designs. It is made up of simple ingredients, most of which can be purchased at a grocery store. However, you may need to visit your local craft store or Amazon for a few items.
If you are looking for a recipe, here is my easy royal icing recipe!
Powdered Sugar
Powdered sugar (aka confectioner sugar or icing sugar) is the main ingredient in royal icing. Make sure it is well sifted and there are no clumps when mixing the icing.
Egg Whites
Some form of egg whites is an essential ingredient in royal icing as this is what allows the icing to harden. Meringue powder, fresh egg whites, or egg white powder can be used. In place of raw egg whites, my preference is to use meringue powder. With meringue powder, you do not need to worry about potential food-borne illnesses that could be a risk with raw egg whites.
Many traditional royal icing recipes use egg whites very safely with great results. This is something I would love to learn more about in the future, but in the meantime, I love my meringue powder.
Water
Lastly, you need water! Water is the ingredient that will allow you to create different consistencies with your icing. Adding more water will create a thinner icing (or flood icing) that is used to cover the base of your cookies. Less water will yield a thicker piping consistency that is better for details. Always add just a few drops of water at a time, it’s always easier to add more water to thin the icing than it is to thicken the icing.
Pro Tip: Use a spray bottle to add water so you don't accidentally add too much water at a time.
Clear Extract (Optional)
You can use a clear extract to add a nice flavor to your royal icing. Vanilla extract is the most common flavor to add to royal icing, but you could experiment with other flavors too!
Corn Syrup (Optional)
Adding a little bit of corn syrup to your royal icing will help it to dry with a nice shiny finish. For more tips on this, I have a whole post on tips to get that shiny look!
Royal Icing Uses
Royal icing has SO many uses. Since it dries hard you can use it to decorate cookies, gingerbread houses, royal icing transfers, and button candy, and it can even be used to make your own sprinkles! With the right consistency, you can create intricate designs on your sugar cookies, which is my favorite use for Royal Icing.
Methods to Dry Royal Icing
Allowing royal icing decorations to sit at room temperature to dry is the best way to harden the icing. The minimum amount of drying time required is typically 6-8 hours. However, this time can be changed depending on several variables including the consistency of the icing, humidity, design, etc. The best way to get your royal icing to harden is to let it sit on parchment paper or wax paper for many hours, place it in front of a fan, or put it into a food dehydrator.
Room Temperature Drying
Royal Icing needs at least 6-8 hours of drying time to thoroughly harden so that it can be touched or moved without creating imperfections. After about 30 minutes to an hour, a thin crust will begin to form on the top of the royal icing. When this happens, it will begin to look like it is dry, but the icing underneath the top layer will not yet have hardened.
Once your cookies are decorated, place them on a cookie sheet lined with parchment paper or straight onto a wire rack or cookie sheet to dry.
Though the standard drying time for most people is about 6-8 hours, there are a few things that could alter that time. The icing consistency will be a large factor in this. The thicker the icing, the quicker it will dry. For flood consistency icing (thinner icing), you will need much more drying time.
Humidity will also have a huge impact on the perfect royal icing drying time. I’ll go more into depth on that later, but essentially, in higher humidity, you will need more drying time.
Using a Fan
Using a fan to assist in drying royal icing is my favorite method. I use a small table fan to help circulate the air around the cookies. This will not only cut down on drying time but will also help the royal icing to dry with a bit of a sheen. The quicker that thin crust forms, the shinier the icing will be, and the better chance you will have to avoid craters.
Simply, allow the fan to blow cool air over the cookies on a baking sheet or drying rack. Just don’t use too powerful of a fan… you don’t want it to blow the wet icing around and mess up your designs or blow the cookies off of your drying surface!
If you have a ceiling fan in the drying room, it won't have a direct impact but any further air circulation in the room will be beneficial.
Food Dehydrator
Food dehydrators are an excellent way to speed up the drying process. As in the name, they will ‘dehydrate’ the frosting by removing the moisture. There is also airflow in the dehydrator helping the royal icing to dry puffier and shinier.
Dehydrators are also great for getting that first layer of the royal icing cookie to dry quickly, so there is less waiting time between your first and second layers of icing.
Don’t worry though, cookies have to be in the dehydrator for a LONG time to dry out the cookie itself. I have used my dehydrator occasionally for royal icing drying, but I am by no means an expert (nor do I have one of the best food dehydrators for this). However, I would highly recommend this post by Borderlands Bakery where she outlines the best dehydrators and more thorough information on using them for your cookies!
Making Your Icing Thicker
Your flood icing (the icing consistency used to decorate larger surface areas of cookies) has to be fairly thin to spread nicely and smoothly across the cookie. Typically, somewhere in the 5-15 second icing range (you can read more about icing consistencies here). The closer you can get this to 15 seconds the quicker it will dry. You will also find that detail consistency icing will dry VERY fast.
Essentially, the thicker you can make your flood icing, the smoother, puffier, and quicker it will dry. Practice Practice Practice is the name of the game when it comes to finding the right consistency for you and for your climate!
Thin Royal Icing = More Drying Time
Thick Royal Icing = Less Drying Time
Humidity and Royal Icing
High humidity is straight-up the devil when it comes to drying royal icing. As moisture from the icing needs to be drawn out for it to harden, having excess moisture in the air is just about the worst thing. I learned this the hard way after letting some cookies sit out overnight in a humid Buffalo summer (and also, I did not have air conditioning). I came to get them the next morning and they were STILL tacky. It was the worst feeling!
Though I’m sure dehydrators would work just fine for humid climates, the trick that works best for me is a window air conditioner. I often let royal icing cookies dry right in front of that AC and it helps them dry super smooth and shiny.
I will admit to having ZERO experience with this, but if you are in a very humid climate, I have heard using a dehumidifier in the room can be very helpful.
Total Royal Icing Drying Time
The amount of time it will take your royal icing to dry will depend on a combination of the consistency of your icing, your climate, and whether you use a fan or a food dehydrator to speed up the process. As in almost every element of royal icing, this may be a trial and error process to find what works best for you!
Royal Icing and Cookie Storage
Once your royal icing cookies are fully dried and hardened, it is now safe to store them in an airtight container. This is my favorite container for decorated cookies as it has a large surface area so you don't have to stack too many cookies on top of each other. Check your recipe for details on how long the cookies will stay fresh. Check out my post on cookie and royal icing storage for more details on the best storage methods!