Home › At the Fountain › Blackberry Floss Syrup
Blackberry Floss Syrup
Blackberry Floss, 1 quart; Plain Syrup, 4 quarts; Fruit Acid, 1 ounce.
This is a fountain formula rather than a kitchen recipe: three components, no method, on the assumption that the dispenser knows how syrups are compounded. Scaled down and translated it makes a workable blackberry soda syrup.
- What "floss" was"Floss" here appears to denote a ready-made concentrated blackberry flavoring base that the dispenser bought in rather than compounded, though the recipe says nothing about how such products were made or sold. Nothing at retail today matches it exactly; a heavy blackberry fruit concentrate or a reduced, strained blackberry puree is the nearest equivalent.
- Plain syrupFountain plain syrup was made much denser than household simple syrup, close to a saturated sugar solution, though the exact proportions differ from one trade formula to the next. Ordinary 1:1 simple syrup will taste noticeably thinner and will not keep as long.
- Fruit acid, quantity ambiguous"Fruit acid" at the fountain usually meant a prepared solution of citric or tartaric acid in water, not the dry crystals, so 1 ounce here is almost certainly liquid measure of a diluted preparation. Because the strength is unstated, treat it as a direction to acidify to taste rather than a conversion: add a little dissolved citric acid at a time until the sweetness sharpens.
- Proportions to scaleThe ratio is 1 part floss to 4 parts plain syrup. For a home batch, 1 cup blackberry concentrate to 4 cups syrup gives the same balance and about 5 cups of finished syrup.
- Yield and servingThe full formula makes 5 quarts of finished syrup, enough for well over a hundred glasses. Fountain practice was 1 to 1 1/2 fl oz of syrup in a glass, filled with cold carbonated water and stirred once.
- Keeping itThere is no preservative here beyond sugar and acid, and the original was compounded for a shop that turned over syrup quickly. A home batch belongs in the refrigerator and should be used within a couple of weeks; discard it if it ferments or clouds.
Soda books like this one were written for the dispenser behind the marble counter, not the cook, which is why the entry reads as a compounding formula: buy the flavoring, cut it with your own plain syrup, correct the acid. American drugstore fountains in the late nineteenth and early twentieth centuries bought flavor bases from wholesale houses and blended them on the premises, and the trade press carried many such ratios. The "fruit acid" step is the mark of a professional formula: sugar syrup and fruit base alone taste flat and cloying against soda water, and a measured dose of citric or tartaric acid was what made the drink read as fruit rather than sweetness.