Food and Environment Safety (Mar 2022)
INFLUENCE OF THE ADDITION OF CHAMOMILE ON THE CONTENT OF TANNINS IN TEA
Abstract
In this work, the influence of chamomile on the content of tannin in the blended green and black teas is investigated by the titrimetric method, which relies on the assessment of tannin oxidation by potassium permanganate with the indicator indigo carmine. The standard procedure of titration was altered in such a way that the dilution of filtrate used during the investigation was decreased by 10 times. This modification made it possible to use the regular 250 ml flasks instead of big and inconvenient porcelain bowls. This way, identification of the point of equivalence became easier and more accurate. Application of this modified method to the determination of tannin in a series of blended teas showed results that are in good agreement with those obtained by the standard methods. They proved that the content of tannin in tea does not depend on the added chamomile and, therefore, this herb does not depress the medical value of the investigated blended teas.