• Title/Summary/Keyword: physicochemical chracteristics

Search Result 2, Processing Time 0.022 seconds

Ecological Studies on the Asan Reservoir. 1. Physicochemical chracteristics and Trophic Status (아산호의 생태학적 연구 1.이화학적 특성과 영양상태)

  • Jun, Sang-Ho;Shin, Yoon-Keun
    • Korean Journal of Ecology and Environment
    • /
    • v.35 no.3 s.99
    • /
    • pp.181-186
    • /
    • 2002
  • To evaluate the eutrophication status of the Asan Reservoir in Korea, physicochemical parameters were analyzed for samples of 19 sampling stations collected in the period from March to November in 1997. Water temperature was in the range of $8.3{\sim}35.3{\circ}^C$, with thermocline appearing in summer. Dissolved oxygen also showed similar verticle variation to temperature. Secchi depth was very shallow with a range of 0.1~1m. Suspended solids ranged from 11.3 mg/1 to 2143.3 mg/1, and seemed to be affected by the amount of rainfall and the standing stocks of phytoplankton. Nutrient concentrations were higher in tributaries, and decreased with downflow. Nutrients were low in the summer and early autumn when algal blooms occur, and high in the early spring and winter. The Trophic State Index showed that the Asan Reservoir is in a hypertrophic condition.

Quality characteristics of Sikhye prepared by different ratio of Seomaeyaksuk (Artemisia argyi H) extract (섬애약쑥 추출물의 첨가 비율에 따른 식혜의 품질특성)

  • Shin, Jeong Yeon;Woo, Yeon U;Jo, Yu Lim;Seo, Weon Taek;Choi, Jine Shang
    • Food Science and Preservation
    • /
    • v.24 no.2
    • /
    • pp.196-205
    • /
    • 2017
  • This study was conducted to increase the functionality of Korean traditional beverage, Sikhye. The Sikhye were prepared by supplementation up to 20% of Seomaeyaksuk extract (SE) and saccharification for five hours (h). During the saccharification, turbidity of SE-added Sikhye (SES) was the highest at two hours of saccharification and then lowered gradually. L vlaue of SES did not show significant difference feduring saccharification, and both a and b value of Sikhye were increased as saccharification time passed and SE addition ratio was increased. The pH before saccharification was not significantly different by SE addition ratio but it was increased to 5.68-5.73 at 5 h saccharification. Soluble solid, total sugar and reducing sugar contents were enhanced as saccharification time and SE addition ratio were increased. The total phenolic compounds contents and DPPH radical scavenging activity showed a similar trend by saccharification time and SE addition. In sensory test, the evaluations of 5% SES and control were not significant different, but 20% SES group showed significant lower evaluation than other groups because strong color and mugwort flavor. From all of these results, physicochemical characteristics and antioxidant activity of SES was improved by SE addition but sensory characteristics was lower. Acceptable addition ratio of SE in Sikhye is determined to be within 15%.