There are several products of Tea together with Cinnamon, Ginger, Peppermint, Rosemary, Lemon Grass Jasmine, Vanilla etc in the Herbal Tea Market. We could also see pure Herbal infusion such as Polpala, Belimal, Iramusu, Gotukola, Karapincha, Chamomile etc. The research was carried out to develop natural herbal tea by using belimal (Aegle marmelos) blended with tea for the value added tea market segment as Belimal is one of the most important herbs grown in Sri Lanka. Belimal is the most famous herb used as a Herbal infusion (not mixed with tea) for generations. The herb has its significant fragrance, a good and lasting taste and promotes fresh breath. On the other hand, Tea is rich in antioxidants, and herbs are generally known to have lower antioxidant values than Tea (Camellia sinensis). Therefore the Combination, of Belimal with Tea could be used as a major strategy by Tea Exporters to capture the market ever changing international markets as this product includes the natural qualities of Tea and medicinal value of both Belimal and Tea.

The belimal flowers are dried and crushed in order to make belimal powder. Then belimal powder is mixed with Black Tea or Green Tea, and a constant total weight for each and every combination should be maintained. The research was conducted according to Two Factor Factorial Design with three factors at two levels as two experiments to the Black Tea and Green Tea. Both experiments consisted with 4 treatment combinations. The Black Tea or Green Tea blend with belimal powder according to the percentages (25% and 50%) while changing brewing time (3 minute and 5 minute) in both experiments. Data was collected through a standard sensory evaluation sheet. The sensory evaluation was conducted by ranking method separately, where company Tea Tasters evaluated color, strength, taste and aroma to check the overall quality in both two experiments. MINITAB was used to analyze the data by using Kruskal Wallis test and Conover- Inman method is used for select the best treatment combination.

 

Crushing

Table 1: Treatment combination for Experiment 1

Treatment (Sample Code)	Black Tea	Belimal Powder	Brewing Time	Total Weight
001	7.5g	2.5g	3 minute	10g
002	5.0g	5.0g	3 minute	10g
005	7.5g	2.5g	5 minute	10g
006	5.0g	5.0g	5 minute	10g

Table 2: Treatment combination for Experiment 2

Treatment (Sample Code)	Green Tea	Belimal Powder	Brewing Time	Total Weight
003	7.5g	2.5g	3 minute	10g
004	5.0g	5.0g	3 minute	10g
007	7.5g	2.5g	5 minute	10g
008	5.0g	5.0g	5 minute	10g

Null Hypothesis (H₀) - There is no significant difference of overall sensory quality between treatment combinations.

Alternative Hypothesis (H₁) - There is a significant difference in overall sensory quality between treatment combinations.

Decision Rule

Reject H₀ if, Statistical test “H” value (calculated value) > Critical Chi- square value at α = 0.05 or

                     Statistical test “P” value < Critical α value (0.05)

Table 3: Results of Kruskal Wallis Test for Experiment 1

Treatment                N              Median                Ave Rank                    Z

1                               7              10.500                   11.1                        -1.27

2                               7              24.000                   22.0                         2.79

5                               7                6.000                     8.1                         -2.36

6                               7              19.500                   16.8                          0.85

Overall                   28              14.5      

H = 11.76   DF = 3   P = 0.008

H = 11.97   DF = 3   P = 0.007 (adjusted for ties)

Table 4: Results of Kruskal Wallis Test for Experiment 2

Treatment                N               Median              Ave Rank                      Z

3                               7                9.500                     8.9                         -2.07

4                               7              21.500                   17.4                          1.09

7                               7              21.500                   19.9                          2.02

8                               7                9.500                   11.7                         -1.03

Overall                   28              14.5

H = 7.95   DF = 3   P = 0.047

H = 8.09   DF = 3   P = 0.044 (adjusted for ties)

In both experiments belimal powder percentage and brewing time was significant at P<0.05. There is a significant different in overall quality between treatment combinations at H>7.815.

According to Conover-Inman method, was selected best treatment combination such as treatment combination 002 and 006 in experiment 1 and treatment combination 004 and 007 in experiment 2.

R (crit.) = t _{(N-k, α/2)}. {[N (N+1) ÷12][(N- 1- H) ÷ (N- k)]}^1/2 [(1÷ n_i )+ (1 ÷ n_j)]^1/2

               = t _{(28 – 4, 2.5%)}  {[28 (28 + 1) ÷ 12][(28 – 1 – 8.09) ÷ (28 – 4)]}^1/2 [(1÷ 7) (1÷ 7)]^1/2

               = 8.0319

Decision Rule

Treatment Combination is significantly different from others (*) if,

Difference of Average Ranks > Critical Conover-Inman value

Table 5: Differences of Average Ranks and Indication with * marks in experiment 1

Treatment	005	001	006
001	3.0
006	8.7  *	5.7
002	13.9 *	8.2 *	5.2

Table 6: Differences of Average Ranks and Indication with * marks in experiment 2

Treatment	003	008	004
008	2.8
004	8.5 *	5.7
007	11.0 *	8.2 *	2.5

Then according to the cost analysis treatment combination 002 and 006 are similar costs in experiment 1 and treatment combination 007 less expensive than treatment combination 004 in experiment 2. 

Table 4.15: Nutrient Test Results of Treatment 007 for 500g Sample 

Test/Unit	Method	Results
Carbohydrate, percent by mass	By difference	64.6
Protein, percent by mass	Pearson’s Chemical Analysis of Food	6.0
Fat, percent by mass	Pearson’s Chemical Analysis of Food	Not detected
Fibre, percent by mass	Pearson’s Chemical Analysis of Food	11.4
Moisture, percent by mass	Pearson’s Chemical Analysis of Food	8.6
Sugar, percent by mass	Pearson’s Chemical Analysis of Food	Not detected
Energy, Kcal 100g-1	By calculation	282
Caffeine, percent by mass	ISO 10727	2.4

The results revealed that percentage of belimal powder and brewing time have some considerable effect to the final product in the research project. According to the sensory analysis and cost analysis, treatment combinations 002 and 006 are preferable for value added tea market as black tea blend with belimal and treatment combination 007 is more useful for value added tea market as green tea blend with belimal.