This is an excerpt from Ouverture de Cuisine
(France, 1604 - Daniel Myers, trans.)
The original source can be found at
MedievalCookery.com
To prepare sugar for casting images & fruits. Mix melted sugar with rose water as much as you would like to have, & let it boil a long time until it becomes like syrup, when boiling add two well beaten egg whites, at the end the sugar will be very white, then pass the melted sugar through a fine sieve to separate out the egg white, then put the sugar back on the fire, & let it boil a long time, stirring the sugar with a spatula, casting it on top, if you see that it falls like snow then it is cooked enough, then take it from the fire, it must always be mixed with a spatula that it will become like little grains & little bubbles, then cast it in the form of fruit or images as wanted.