Anthocyanin Standardization & Grades
Anthocyanins are the water-soluble pigments that give the calyx its deep red color. Roselle carries them mainly as delphinidin and cyanidin glycosides in which the sugar is sambubiose, a two-sugar unit that is a feature of the plant. The calyx also holds organic acids, including hibiscus acid, and phenolic acids such as protocatechuic acid. The botanical entity is Hibiscus sabdariffa L., a plant of the Malvaceae, and the part used is the calyx of the flower, which is the red, fleshy structure around the seed pod.
| Grade | Assay & Method | Where It Fits |
|---|---|---|
| 5% Anthocyanins | UV, pH differential | Tea-style blends and drink powders |
| 25% Anthocyanins | UV, pH differential | Capsules and tablets with small fill |
For hibiscus, for hibiscus, the two grades differ by a factor of five. For hibiscus, the 25% grade is a pigment concentrate that supplies a defined load from a small fill. The 5% grade holds more of the fruit acids and sugars of the calyx, so hibiscus extract at this level has a tart, cranberry-like flavor and suits tea-style blends and drink powders. The calyx is also supplied as a 10:1 ratio extract, the Hibiscus (Roselle) Extract Powder, as a milled calyx, the Hibiscus Flower Powder, and the simple phenolic acid is listed as 3,4-Dihydroxybenzoic Acid 98%. Ornamental hibiscus species are different plants. Hibiscus extract at 25% is the more concentrated of the two grades, and hibiscus extract at 5% is the fuller one. The calyces swell and turn red as the fruit matures.












