Hello.

Is there any rules when " to add meringue to the mixture or mixture to the meringue"?

Thank you all 

What are you making?  Are you referring to meringue powder or whipped egg whites?

Hello

I am sorry for delayed reply. 

I am talking about whipped Egg whites.

Thank you.

It depends on what you are making.  For example with angel food cake you add the flour mixture gradually to the whipped egg whites and fold it in.  I make a vanilla cake that you gradually fold the whipped  egg whites into the batter and fold in.

What are you making?  What does the recipe say?  It will matter which way you do it.  The whipped egg whites are usually part if not all of the leavening agent in some cakes.

Hello

I am not in a process of any cakes now, but just found that those ingredients switching spots during mixing. So my question:

Any reason? If YES - what is switching effect.

 Best regards

Well for example in an angel food cake - you whip up the egg whites with the salt, cream of tartar powder, salt and sugar.  Since the whipped egg whites are the leavening agent and really the main ingredients and as such, also really fluffy and light and fragile-you are then going to gradually sift your flour and additional sugar over the egg whites. Then you are going to gently fold in that which you have sifted over, in order to incorporate the mixture.  But because egg whites are not structurally strong, this method helps you avoid deflating them. If you mixed it the other way around, the cake wouldn't rise.

In my vanilla cake recipe the cake structure is more firm. It has butter and sour cream and a higher ratio of flour to sugar and has additional leavening agents in the form of baking soda and baking powder. And another reason it has egg whites instead of whole eggs is so the cake is closer to a pure white as opposed to the more yellow colour of the white cakes using whole eggs.  But the egg white purpose in this recipe is also to make the cake texture a bit lighter. So in this recipe the whipped egg whites are added gradually to the cake batter and gently folded in so as not to deflate them. If you did the reverse and added the other ingredients to the whipped egg whites, the weight of the batter would deflate the egg whites and defeat their purpose.

So this is why it is important to follow a recipe's method or you won't get the right results.

Thank you so much for such detailed guide. So the conclusion is: if cake has a traditional leveling agents and contains butter - whipped egg whites added to side ingredients. If there's no  leveling agent other then egg whites itself -  so all side ingredients added to whipped egg whites.

 Thank you so much.  Irina

Yes and no, haha.  Don 't put heavy ingredients on top of whipped eggwhites or they will be deflated and in deflating them even if they are only partially responsible for the cake rising, it won't rise as well or at all if it is angel food.

:-)  Thank you. I will be careful. You been very helpful.

Best regards 

My pleasure. You are very welcome.