Recipe for making maidenhair fern (capillaire) syrup, sirop capillaire, at home.

Sirop Capillaire is an infusion of maidenhair fern syrup and orange-flower water, used for flavoring cocktails. As Escoffier did not include a recipe in Guide Culinaire, this is based on others, notably those of Jerry Thomas.

True capillaire syrup was initially made in the 1700s with maidenhair fern. But over the years, some thought the flavor detracted from their beverages and eventually settled on a sugar syrup simply flavored with orange (curaçao or orange-flower water).

This syrup is used in the recipe for Bavaroise (Escoffier, 4995).

Mise en place for sirop capillaire.

Start with 28 grams of fresh maidenhair fern leaves, adiantum pedatum (add-ee-ANN-tum puh-DAY-tum), rinsed well in cold water. Use organic or culinary-grade if you can find it. The last thing you want to ingest is a delicious, but pesticide-laced, cocktail… Place in a large bowl.

Combine 1000g water with 500g granulated sugar and bring to a boil until the solids are dissolved.

Clarified syrups

Pre-20th century recipes call for loaf-sugar, then clarifying with egg whites. This was to bring out any impurities from the unrefined sugar. With today’s bleached and refined granulated sugars, the clarification step is un-needed. Unless your syrup turns out cloudy.Then you could clarify with egg-whites if you really wanted. Stir in a couple of egg whites, boil, then skim the scum off the top. Strain.

Pour the syrup over the fern leaves and infuse until the syrup cools to room temperature. Strain. Then add 10g (or to taste) of orange-flower water.

Strain again through a funnel into a 750mL glass bottle. (I save my Champagne bottles expressly for syrups!) Cap and refrigerate for future use.

Ingredients
1000g water
500g granulated sugar
28g fresh maidenhair fern leaves
10g orange-flower water

From the Books

346. Sirop Capillaire. (Maidenhair Syrup.)

1 lb. of maidenhair herb.
5 1/2 gallons of boiling water.

Macerate till cold; strain without pressing, so as to get 5 gallons; take the whites of 3 eggs beaten to froth, and mix them with the infusion; keep back a quart of the liquid; then dissolve and boil in the above 80 lbs. of sugar by a good heat; when the scum rises, put in a little from the quart of cold liquid, and this will make the scum settle; let it raise and settle 3 times; then skim, and when perfectly clear add 1/2 a pint of orange-flower water; then boil once up again and strain.

“This beverage ought always to be made with boiling water, and allowed to concoct and cool for a day or two before it is put on the table. In this way, the materials get more intensely amalgamated than cold water and cold whiskey ever get.”

65. Capillaire. — Put a wine-glass of Curaçoa into a pint of clarified syrup, shake them well together, and pour it into the proper sized bottles. A tea-spoonful in a glass of fair water makes a pleasant eau sucré…

66. Another recipe for making Capillaire. — To one gallon of water add twenty-eight pounds of loaf-sugar; put both over the fire to simmer; when milk-warm add the whites of four or five eggs, well beaten; as these simmer with the syrup, skim it well; then pour it off, and flavor it with orange flower water or bitter almonds, whichever you prefer.

– Thomas. How to mix drinks, 1865

Sources:
Le Grand d’Aussy. Histoire de la vie privée des François, 1782.
Jerry Thomas. How to mix drinks, 1865.