I've made royal icing on several occasion without incident. It has always turned out well. However, the past two times I've made it, the icing won't harden. I made coral with royal icing and had to stick it in the oven on low heat to dry it out. Also, a couple of weeks ago when I made it, the icing turned yellow. Does anyone have any advice or know what could be causing the problem? Thanks!!

I don't know about the yellowing; but about the icing not hardening: Are you sure that your tools are all 100% grease free? Wash everything you're going to use to make the royal and decorate with it in very hot water with a good dish detergent (I use Dawn, cuts the grease right off!) I soak any tips I'm going to use in very hot water with the Dawn; and wash my KitchenAid mixer's bowl and paddle several times in the hot water and detergent.

If there is any grease present, your royal won't turn out right.

It could also be any underlying grease that is causing the discolouration.

Have you ever cooked beans in a plastic bowl in the microwave, and it leaves a reddish orange on the plastic? That will seep right into your royal icing and turn it orange. So it could be something youve previously had in the bowl.

Even if you cant see it, doesnt mean its not there. I always use either a glass bowl, or stainless steel bowl when making RI.

If there is any grease present the icing will remain soupy and not even look like royal.

Is your meringue powder old?

What brand of powdered sugar are you using? Did you change brands?

I'm using the same brand of powdered sugar. I thoroughly wash my stainless steel bowl with Dawn and hot water prior to using. However, maybe it's not getting it completely off, and there is still just enough grease on it to cause problems. I have three KA mixers, and one I rarely use. I may use that particular one strictly for my royal icing and see if it turns out better. If so, then the grease is the answer.

I live in Florida. Could humidity play a part in it?

Humidity will slow the drying time down.

I had some icing I made and use weeks later dry with a off white color. I figured that it had something to do with it being 'old' but I'm not sure. I know the fresh icing I made dried white.

I do know that dried royal can yellow but it is usually over time and doesn't happen quickly.

MP gets darker in color, so if it was old MP maybe that caused the problem?

I seriously doubt it was greasy myself. From my understanding grease won't let the egg whites/mp whip up probably, so you'd know before you even got to work with it if there was something wrong.

I don't have a dish washer so I wash everything by hand with dawn. I don't make any special effort to use only items that haven't touched bc like couplers and tips, nor do I go to the effort of wiping my bowls and things down with vinager.

If it helps, Cakelove suggest swishing a bit of vodka around in your bowl to get out all the grease. Myself, I give everything a quick wipe down with white vinegar even after I wash it. I have a silicone spatular that is only for RI just so I won't have to deal with the grease on that kind of surface.