Chemical and sensory analyses of spray- and freezedried extracts of rooibos tea (Aspalathus linearis)

Spray- and freeze-dried rooibos tea extracts were prepared, and the soluble solids which precipitated upon cooling of the concentrate were isolated. Their effect on composition and sensory qualities of the dried tea was determined. Preparation of soluble rooibos teas resulted in significant flavour differences, but no preference for freshly brewed tea was found. The method of dehydration and removal of precipitated solids did not affect the flavour of the dried tea extract significantly. Removal of the precipitate resulted in marked decreases in total polyphenol, flavonoid, tannin, flavanol and proanthocyanidin content of the dried soluble product.