caramelize the way real sugar does. And  because erythritol is a sugar alcohol,  

there will be a strange cooling  sensation when you eat it.

Allulose does not have the above  problem at all. But note that the  

sweetness of Allulose is only 70% of that of  sucrose, so to achieve the same sweetness,  

more Allulose needs to be added, and it may also  increase the volume of the finished product.