Preheat the oven to 400°F. Put the dry ingredients for the "red" fritters on a board to form a pile. Separately, mix the egg with oil, orange juice and zest then pour in the middle of the pile. Knead until you have a smooth dough and set aside.
Form a pile with the dry ingredients for the cocoa fritters; again,
mix the egg with oil, orange juice and zest then pour in the middle of the pile and knead until you have a smooth dough.
Line two baking trays with parchment paper. Form 1-inch balls out from the cocoa and white dough and line them on the trays.
Bake the fritters for 10 minutes, then allow them to cool down.
Mix water and Alchermes and use this mixture to brush the white fritters. Sprinkle with brown icing sugar and serve.
The "castagnole" fritters keep well at room temperature in an airtight container up to 6 days.