유자의 화학적 특성 및 아질산엄 소거작용

Chemical Properties and Nitrite Scavenging Ability of Citron (Citrus junos)

대표적인 유자 산지인 남해(I, II), 통영 및 고흥에서 유자를 구입하여 과육 및 과피로 각각 분리한 후 이화학적 성분 및 아질산염 소거능을 측정하였다. 4종의 유기산이 검출되었으며, citric acid의 함량은 $10.2\pm0.14\~17.7\pm0.17\pm0.17\;g/100g$이었으며, 고흥산 유자의 과육 및 과피에서 각각 $17.3\pm0.16\;g/100g,\;17.7\pm0.17\;g/100g$으로 가장 높게 정량되었다. 무기물은 산지에 따른 차이가 작았으며, 칼륨의 함량이 $1,332.4\pm2.31\~2,308.5\pm3.25\;mg/100g$으로 가장 높았다. 유리아미노산 은 proline, asparagine, glutamic acid가 비교적 높게 함유되어 있었으며 통영산 유자 과피에서 총 326.9 mg/100 g으로 가장 높게 정량되었다. 유자 착즙액의 전자공여능은 시료액의 농도가 증가함에 따라 상승하였으며 $0.1\~0.2\%$ 농도의 산지별 시료액 첨가시 $80.0\%$ 이상의 효과가 나타났다. SOD 유사활성은 $0.01\~0.2\%$의 시료농도에서 $10.2\pm0.50\~20.1\pm0.77\%$였다. 아질산염 소거능은 pH 1.2에서 $0.1\~0.2\%$시료액 첨가구에서 모두 $73\%$이상의 아질산염 소거능을 나타내었으나, pH 4.2에서는 모든 시료액 첨가구에서 $27\%$ 이하로 낮았다.

The chemical properties and nitrite scavenging ability were analyzed which on a citron (Citrus junos) of 4 kinds purchased in different regions [Namhae (I, II), Tongyoung and Koheung] in Korea. Four kinds of organic acids were determined. Citric acid contents in flesh and peel of citron were $10.2\pm0.14\~17.7\pm0.17\;g/100g$. The organic acid content was the highest in citron purchased from Koheung. Total mineral content in citron was in a range of $2,844.3\~4,022.4$ mg/100 g, the potassium content was the highest in the range of $1,332.4\pm2.31\~2,308.5{\pm}3.25\;mg/l00g$. The major free amino acid from citron were proline, asparagine and glutamic acid. And the highest in peel of citron purchased from Tongyoung by 326.9 mg/100 g. However, the kinds and contents of chemical components in citron were somewhat different among various regions. The electron donating ability using DPPH method of citron juice was more than $80.0\%$ at the concentration of $0.1\~0.2\%$ and it was stronger by increased the juice concentration in the reaction mixture. SOD-like activity showed $10.2\pm0.50\~20.1\pm0.77\%$ at the concentration of $0.01\~0.2\%$. The nitrite scavenging ability was pH and sample concentration dependent. It was the highest at the pH 1.2 and more than $73\%$ in $0.1\~0.2\%$ citron juice. On the contrary in all concentration of added citron juice lower than $27\%$ at pH 4.2.