In a large saucepan over low heat beat syrup, molasses, butter and sugar together, stirring until sugar has dissolved. Remove from heat and let cool slightly.
Add the flour, soda, spices, lemon juice and grated rind. Mix well to make a stiff dough. Chill for several hours.
Shape into long rolls about 1 inch in diameter. Cut into pieces 1 inch long with a sharp knife.
Dilute egg whites with 2 tablespoons of water, and beat until frothy. Brush over cut sides of cookies after you have placed them on a greased cookie sheet.
Bake 15 minutes in a preheated 350° oven.
This recipe makes the very hard peppernuts (Pfeffernüsse) which are an international language. These will keep indefinitely if stored tightly covered.