Abstract:
This research aimed to develop the lemon grass herbal tea product in order to satisfy customers
requirements by applying quality function deployment and design of experiments technique. Due to the survey
of the old consumers groups aged between 25 and 49 in Muang district, Songkhla province on herbal tea in
local area , it was found that 42% of consumers seldom had consumed herbal tea products , not only lemon
grass tea but also the percentage of padanus tea and ginger tea were 47% and 39% respectively. Hence, the
establishment of House of Quality was to define technical characteristics, the relationship among the technical
characteristics, and the relationship between customers requirements and technical characteristics by consid-
ering prioritization and relationship. The products can be developed into the acceptable important technical
data. The lemon grass tea product was developed by mixed herbal tea by using mixture design approach.
The ingredients in the formula were lemon grass : pandanus : ginger at the appropriate ratio of 60.6:39.4:0. The
optimized conditions i.e. temperature and time were also determined by using factorial in completely randomiz-
ing design. It demonstrated that tea had been roasted by 60oC with the duration of 15 minutes. As the results
of testing on consumers , the average favor scores of aroma, color, taste and overall favor were 7.15, 6.92, 7.80
and 7.56 respectively. The acceptance after product development was considered increasing up to 84.0% with
61.5% and the purchase decisions were increased up to 76.0% with 58.3% respectively.