The great eggless royal icing experiment

The results are in: I have completed my egg-free royal icing experiments. I made up a small batch of each of the following recipes and tried piping the icing and gluing small pieces of gingerbread together to check the bond. All the batches of icing were left for 12 hours to see how well they would dry out.

Each recipe should be suitable for people who have an egg allergy or are vegan.

BBC Food's Egg Free Royal Icing

Link to original recipe

The ingredients for this recipe are icing/confectioner's sugar, lemon juice and glycerine. (Edit: if you are vegetarian or vegan you will need to check on the label or with the manufacturer that the glycerine is plant or synthetically derived and not animal fat-based.) I made two batches. The first time I added the liquid ingredients (lemon juice and glycerine) too quickly and ended up with an icing that was a little soft. The second batch piped a bit better. This was the icing that "touch-dried" the quickest and hardened the best. The glycerine was the surprise ingredient - in theory its function is to ensure that the icing doesn't get too hard.


Small stars piped in a row; two pieces of gingerbread glued together

• Shape: Good (the photo at the top of this post, is this icing)
• Bonding: Good
• Hardness: Very good
• Colour: Good - slightly cream
• Taste: Good - pleasant slightly citrus
• Recommended uses: Gingerbread house glue; Cookies that need to be stacked.

Vegetation's Vegan Royal Icing

Link to original recipe

The ingredients in this recipe are egg substitute, water, cream of tartar and icing/confectioners sugar. I chanced on this recipe, while looking for a standard royal icing recipe - my intention was simply to add an egg substitute. The ingredients and method are very close to a regular royal icing. The purpose of the cream of tartar (an acid, like lemon juice) is to help the icing hold its shape and dry out. I only made one batch, as by this time I had wised up about how careful you need to be in adding the liquid! I did need to add more water at the end (as the recipe suggests) to get the right consistency.

The egg replacer I used was Orgran "No Egg", an Australia-manufactured product, which is available in supermarkets and health food stores. I'm guessing that the original recipe probably used "Ener-G Egg Replacer". Both products have a similar composition, comprising potato and tapioca starches and a vegetable gum called methycellulose.

Small piped stars

• Shape: Very good
• Bonding: Good
• Hardness: Good, though it didn't completely dry out
• Colour: Excellent - snowy white with a slight sheen
• Taste: Good - neutral, sweet
• Recommended uses: Piping onto cakes; Any place where shape but not strength are important.

Veglicious' Vegan Icing

Link to original recipe

The ingredients in this icing are icing/confectioner's sugar, cornstarch, lemon juice and soy milk. Soy is a common allergen, so I wasn't able to test the recipe properly using the milk. Instead I used a little extra lemon juice. I made two batches of this icing, as the first was incredibly soft and didn't pipe well. The second batch was stiffer, but still wouldn't hold its shape as it was piped. The icing bonded the gingerbread pieces, but oozed. But to be fair, the recipe wasn't made as it was intended. Without understanding the food science behind each ingredient it is difficult to say why the icing remained soft, but it could be that the soy milk is a key ingredient. It would be worth noting however, that when making "real" royal icing you would generally avoid sugar containing cornstarch (an ingredient in this recipe), as it tends to make the icing soft.

This did start out as a line of piped stars!

• Shape: Poor
• Bonding: OK - it would join cookies together and set
• Hardness: Poor - the icing formed a crust but didn't dry out
• Colour: Good - slightly cream
• Taste: Good - pleasant slightly citrus
• Recommended uses: This would be a very good icing if you'd like to add colouring. The acid in lemon and cream of tartar used in the previous recipes can alter some colours (e.g. violet may become blue).

Conclusion

Firstly a disclaimer ... all these experiments have been carried out in an unscientific manner in my home kitchen. I did it all to the best of my ability, but really the results I have given here are just my interpretations and opinion!

Having said that, I am going to try and use the BBC recipe for gluing this year's gingerbread house and Vegetation's recipe for piping decorations onto my (fondant covered) Christmas cake. The sad reality is, however, that none of the eggless versions of the icing replicates all of the properties of real royal icing. If you have an extra special icing project, it would probably be wise to make a small batch as a test run.

I hope you find the information here helpful. I would love to hear how you go, or if you have a great recipe that you would be willing to share.

Edit: 24 Dec 08, see my gingerbread cottage made with egg-free icing (the BBC recipe) over here.