최근 우리나라는 경제 수준의 향상, 서구적인 식생활 및 각종 스트레스로 인해 만성질환이 증가하고 있으며, 이에 따라 천연물을 이용한 건강 차에 대한 소비자의 관심과 요구가 높아지고 있다. 국내산 뿌리채소는 식품소재로 활용가치가 높으나 영양 생리활성 연구나 제품화 연구가 매우 미비한 실정이다. 따라서 본 연구에서는 국내 다소비 뿌리채소 12종(우엉, 연근, 참마, 순무, 삼채, 당근, 마늘, 도라지, 감자, 토란, 양파, 더덕) 가운데 항산화능이 우수한 뿌리채소 2, 3종을 선정한 후 로스팅 처리로 맛과 항산화활성을 강화시킨 후 건강 차를 개발하고자 하였다. 국내 다소비 뿌리채소 12종을 열수 추출한 후 total polyphenol 함량을 측정한 결과, 우엉은 72.09±0.75 mg TAE/g, 연근은 58.86±0.57 mg TAE/g로 측정되어 12종 가운데 1위, 2위를 차지하였다. DPPH radical 소거능을 측정한 결과, 우엉은 90.21±0.91%, 연근은 87.83±1.20%로 12종 가운데 1위, 2위를 차지하였다. 로스팅한 우엉과 연근 혼합한 7종의 차 시료를 제조하여 항산화능을 측정한 결과, 90℃에서 우려낸 연근차 45 mL와 우엉차 135 mL를 혼합한RL1RB3의 total polyphenol 함량이 99.75±0.52 mg TAE/g, DPPH radical 소거능은 88.86±0.49%로 나타나 항산화 활성이 7종의 차 가운데 1위, 2위를 차지하였다. 로스팅한 우엉과 연근 혼합한 7종의 차 시료를 제조하여 관능평가를 한 결과, 향에 있어서는 90℃에서 우려낸 연근차 120 mL와 우엉차 60 mL를 혼합한 RL2RB1 시료가 가장 우수하였으나, 연근차 90 mL와 우엉차 90 mL를 혼합한 RL1RB1가 맛, 색, 전반적인 기호도에서 가장 우수한 점수가 나타났다. 즉, 항산화 활성이 가장 우수한 시료는 RL1RB3이었으며, 맛이 가장 우수한 차 시료는 RL1RB1이었다.
Chronic diseases have been recently increasing in South Korea due to economic improvement, western diet, and various types of stress. Accordingly, there have been increasing consumer interest and demand for natural substance-based health tea that helps to improve chronic diseases. Domestic root vegetables are highly useful as food material but there are very few studies on nutritional physiological activity or commercialization. Therefore, the present study developed health teas by strengthening the physiological activation effects through roasting process after selecting 2 or 3 root vegetables with excellent antioxidant capacity from 12 largely consumed domestic root vegetables, namely burdock root, lotus root, yam, turnip, Allium hookeri, carrot, garlic, bellflower root, potato, taro, red onion, and lanceolatae. Hot water extraction was performed on the 12 largely consumed domestic root vegetables and then the total polyphenol content was measured. The result showed that 72.09±0.75 mg TAE/g was measured for burdock root and 58.86±0.57 mg TAE/g for lotus root, taking the first and second places among the 12 varieties. Upon measuring DPPH radical scavenging activity, burdock root and lotus root showed 90.21±0.91% and 87.83±1.20%, taking the first and second places among the 12 varieties, respectively. After roasting burdock root and lotus root, 7 different teas were made and antioxidant capacity was measured. The result showed that for 45 mL of lotus root tea and 135 mL of burdock root tea (RL1RB3) infused at 90℃, the total polyphenol content was 99.75±0.52 mg TAE/g and DPPH radical scavenging activity was 88.86±0.49%, exhibiting the most excellent antioxidant activity. After roasting burdock root and lotus root, 7 different tea samples were made and sensory evaluation was performed. The result showed that 120 mL of lotus root tea and 60 mL of burdock root tea (RL2RB1) sample had the highest aroma and 90 mL of lotus root tea and 90 mL of burdock root tea (RL1RB1) had the most excellent flavor, color, and overall preference. In conclusion, 90 mL of lotus root tea and 90 mL of burdock root tea (RL1RB1) is excellent for flavor but it is anticipated that if 45 mL of lotus root tea and 135 mL of burdock root tea (RL1RB3) is developed as a cold beverage, then it will be able to satisfy the demand of the general public as a health tea with not only sensuality but also excellent antioxidant activity.