Abstract:
Herbal tea products are popular among health conscious people in Sri Lanka as value
added products. Masbedda is commonly used as a herbal medicine which can reduce
blood sugar and serum cholesterol levels. A ready-to-consume herbal tea bag with
Masbedda (Gymnema sylvestre L.) leaves was developed as a value added tea product.
Triangle Sensory Test was carried out to determine the highest percentage of Mabedda
leaves that can be added to black tea without adversely affecting the sensory properties
of the final product. The physicochemical properties (dry matter and ash content) of
the final product, named “Ruhunu” herbal tea, were also determined using the standard
methods of the SLSI. Microbiological tests, namely Total Plate Count, Coliform and E.
coli tests were also carried out to determine the microbiological properties of “Ruhunu”
herbal tea. The sensory properties of “Ruhunu” herbal tea was compared with other
commercial herbal tea products and commercial non-herbal tea products using a 5 -point
hedonic scale. A sensory panel consisting of 35 panelists was used in all sensory
studies. Furthermore, a clinical test wa§ conducted to determine the effect of “Ruhunu”
herbal tea on absorption of sugar into the blood stream after a standard meal. Sensory
data were analyzed using Kruskal Wallis non- parametric test using the SPSS statistical
package.
It was observed that addition of 5% or more Masbedda leaves to black tea adversely
affected the sensory properties of the herbal tea. Therefore, “Ruhunu” herbal tea bags
were produced by mixing 4% of Mabedda leaves with black tea. The dry matter
content and ash contents of “Ruhunu” herbal tea were 91.62% and 6.39%, respectively.
Microbiological examination revealed that the product contained a total aerobic plate
count of 2.1*106 CFU/g and a coliform count of 103 CFU/g. Moreover, “Ruhunu”
herbal tea did not contain E. coli. In sensory evaluation between commercial herbal tea
products and “Ruhunu” herbal tea, the total sum of ranks of “Ruhunu” herbal tea for
taste, colour, aroma and overall acceptability were 136, 164, 149 and 158, respectively
and “Ruhunu” herbal tea showed significantly (P<0.05) higher sensory properties. In
sensory evaluation between commercial non-herbal tea products and “Ruhunu” herbal
tea, the total sum of ranks of “Ruhunu” herbal tea for taste, color, aroma and overall
acceptability were 131, 140, 120 and 129, respectively and “Ruhunu” herbal tea
showed moderately higher sensory scores. The consumption of “Ruhunu” herbal tea
after a standard meal appeared to decrease the absorption of sugar into the blood stream
in human volunteers. It can be concluded that herbal tea with 4% Masbedda leaves can
be produced without changing the sensory properties. Further, the “Ruhunu” herbal
tea, which shows significantly higher (P<0.05) sensory properties, can effectively
reduce sugar absorption into the blood stream after a meal. “Ruhunu” herbal tea may
be recommended for use by diabetes patients as an alternative medicine.
