タイトル |
茶葉アスコルビン酸の簡易測定法 |
担当機関 |
京都府立茶業研究所 |
研究期間 |
2000~2000 |
研究担当者 |
原口健司
木村泰子
|
発行年度 |
2000 |
要約 |
荒茶及び生葉の2%メタリン酸抽出液をPVPPで除タンニンすることで、小型反射式光度計(RQflex)で簡易にアスコルビン酸を測定できる。
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背景・ねらい |
アスコルビン酸は茶の保存状態の指標になる重要な成分であり、その分析についてはHPLC法や比色法によるのが一般的である。しかし、高価な装置を使用しなければならず、現場段階には普及していない。
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成果の内容・特徴 |
- 被検液の調製は、粉砕した荒茶1gを25ml2%メタリン酸で30分間撹拌抽出後、ろ液を約200mgのPVPP(ポリビニルポリピロリドン)で30分間撹拌処理(除タンニン)して行う(図1)。
- 生葉については4gを100ml2%メタリン酸中で乳鉢、ホモジナイザー等で均質化した後、30分間撹拌抽出し、以下荒茶同様に操作する(図1)。
- アスコルビン酸用試験紙(Merck社製)を調製した被検液に約2秒間浸した後、試験紙を軽く振って余分な水分を除き、反応時間(15秒間)内に小型反射式光度計(商品名:RQflex Merck社製)で測定する。
- 荒茶・生葉ともHPLC法分析値と高い相関を示す(図2、図3)。
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成果の活用面・留意点 |
- 簡易法はアスコルビン酸量に基づく荒茶及び生葉の保存状態の把握等、品質管理に活用できる。
- 簡易法はHPLC法より値が高くなる傾向があるため、相対評価に適する。
- 水で抽出した場合は妨害物質の影響を受けるため、2%メタリン酸で抽出することが必要である。
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図表1 |
![210973-1.jpg](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/210973-1.jpg?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECUaDmFwLW5vcnRoZWFzdC0xIkgwRgIhAMOhV9JI2K3mEoaCEzMpU9mU639ESZa%2Fe4lTY8HqmnErAiEAuvvR2G7o1%2FN7JLOEWdSnvhVNsIjRjLho3%2B5Bdcfd7fwqmQQIzv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw1MzIzMzEwNzIwNDEiDF1Kbw4b6897mowRtCrtAwfTyYC901MyOT1I7%2FPY97cAqaIKnSLc6JAEzt3m8AzcGqXhKi8Xgi%2FOBUXCIvxlGjDyaOp6dHkr6B9HL%2Fc%2Fl1A0Zr1Bo4c0NCPAOki84FeIrHJDbw9b7CDqMgLse7Tt8AagUR8uuXSgtnpWwTVGJ8%2BAF3x5lmTjB91AvM3XJp20Rk6C6PeERYPyIqvYUbkVqtTvO5vi5kTrV8Npi3z1xf3jtTo%2BjE8aeDGsdDa6L%2FTt%2Fm3tRBLPzded3YycGtteymonzx0CjMiL9W41rzbzprrjOdPfZ8b%2FU%2BS5nxlhMk1KHKCxFxBJjsjlA6VCrVy2%2FH5VaM1Eup6AuOrqKzU1V27xzXx2PB66qWsOjZJY97w93uDERL8RXAgfGk%2Bnl20gTK%2B84isJYJvEj6p5qcuxiP4e9jqp9UkE41PBwQBpwxPk0m%2Bt5eBBct11l7PWPX3QFm6Yxuw%2F0tasZKiLew%2FcQB0tTFdohEQGGj%2FgtmbRsOgdtYTQt95OvF%2FlmOdVwpwKXkfGGQLsAO0v360XGsMRjug3qXhnpf0axl1JDNA65IObbcKNPWZPX%2BF7kl52oWpka93U0x3y7lPfYh0RffrTiYLzWsJ%2FAhFNjhv0KQsqKUlNxZz5zisbe9%2F%2BaGdPiflu0WpbdDbV5slJUSA%2BH%2Fcw4MnuswY6pQHIDnK8FSFNQ3k5LGnGF0XnBzF9%2FS6GqxvjVop1bjYgsSDqJm45n17RXXg7FjdNsfcWGja7%2F%2B0S9uI86IijFEgHbpCr%2Fpvr%2Fpu5Gf5qZe%2F%2B%2Ba5qtj1KzoRxLllyHGdGlgXTJ7I1YXjEi3Uwc81q5EQQ4fNleqiH%2Bdt1M4h3yOuubgg27Te%2F0q4FBZW0AcL%2B740PAgKQ7I4kHyp1vrHMT485PzUbgLg%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIUYGXEWVE7%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T052624Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=be70aeef36f6e7036052407194efe571ea7256fd48c9f208eaace06826c52932) |
図表2 |
![210973-2.jpg](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/210973-2.jpg?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECUaDmFwLW5vcnRoZWFzdC0xIkgwRgIhAMOhV9JI2K3mEoaCEzMpU9mU639ESZa%2Fe4lTY8HqmnErAiEAuvvR2G7o1%2FN7JLOEWdSnvhVNsIjRjLho3%2B5Bdcfd7fwqmQQIzv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw1MzIzMzEwNzIwNDEiDF1Kbw4b6897mowRtCrtAwfTyYC901MyOT1I7%2FPY97cAqaIKnSLc6JAEzt3m8AzcGqXhKi8Xgi%2FOBUXCIvxlGjDyaOp6dHkr6B9HL%2Fc%2Fl1A0Zr1Bo4c0NCPAOki84FeIrHJDbw9b7CDqMgLse7Tt8AagUR8uuXSgtnpWwTVGJ8%2BAF3x5lmTjB91AvM3XJp20Rk6C6PeERYPyIqvYUbkVqtTvO5vi5kTrV8Npi3z1xf3jtTo%2BjE8aeDGsdDa6L%2FTt%2Fm3tRBLPzded3YycGtteymonzx0CjMiL9W41rzbzprrjOdPfZ8b%2FU%2BS5nxlhMk1KHKCxFxBJjsjlA6VCrVy2%2FH5VaM1Eup6AuOrqKzU1V27xzXx2PB66qWsOjZJY97w93uDERL8RXAgfGk%2Bnl20gTK%2B84isJYJvEj6p5qcuxiP4e9jqp9UkE41PBwQBpwxPk0m%2Bt5eBBct11l7PWPX3QFm6Yxuw%2F0tasZKiLew%2FcQB0tTFdohEQGGj%2FgtmbRsOgdtYTQt95OvF%2FlmOdVwpwKXkfGGQLsAO0v360XGsMRjug3qXhnpf0axl1JDNA65IObbcKNPWZPX%2BF7kl52oWpka93U0x3y7lPfYh0RffrTiYLzWsJ%2FAhFNjhv0KQsqKUlNxZz5zisbe9%2F%2BaGdPiflu0WpbdDbV5slJUSA%2BH%2Fcw4MnuswY6pQHIDnK8FSFNQ3k5LGnGF0XnBzF9%2FS6GqxvjVop1bjYgsSDqJm45n17RXXg7FjdNsfcWGja7%2F%2B0S9uI86IijFEgHbpCr%2Fpvr%2Fpu5Gf5qZe%2F%2B%2Ba5qtj1KzoRxLllyHGdGlgXTJ7I1YXjEi3Uwc81q5EQQ4fNleqiH%2Bdt1M4h3yOuubgg27Te%2F0q4FBZW0AcL%2B740PAgKQ7I4kHyp1vrHMT485PzUbgLg%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIUYGXEWVE7%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T052624Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=cc8885082cc2c9c6e41a94f96471f39c1c386d507b6dc756f603a0fc8ba1045b) |
図表3 |
![210973-3.jpg](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/210973-3.jpg?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECUaDmFwLW5vcnRoZWFzdC0xIkgwRgIhAMOhV9JI2K3mEoaCEzMpU9mU639ESZa%2Fe4lTY8HqmnErAiEAuvvR2G7o1%2FN7JLOEWdSnvhVNsIjRjLho3%2B5Bdcfd7fwqmQQIzv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw1MzIzMzEwNzIwNDEiDF1Kbw4b6897mowRtCrtAwfTyYC901MyOT1I7%2FPY97cAqaIKnSLc6JAEzt3m8AzcGqXhKi8Xgi%2FOBUXCIvxlGjDyaOp6dHkr6B9HL%2Fc%2Fl1A0Zr1Bo4c0NCPAOki84FeIrHJDbw9b7CDqMgLse7Tt8AagUR8uuXSgtnpWwTVGJ8%2BAF3x5lmTjB91AvM3XJp20Rk6C6PeERYPyIqvYUbkVqtTvO5vi5kTrV8Npi3z1xf3jtTo%2BjE8aeDGsdDa6L%2FTt%2Fm3tRBLPzded3YycGtteymonzx0CjMiL9W41rzbzprrjOdPfZ8b%2FU%2BS5nxlhMk1KHKCxFxBJjsjlA6VCrVy2%2FH5VaM1Eup6AuOrqKzU1V27xzXx2PB66qWsOjZJY97w93uDERL8RXAgfGk%2Bnl20gTK%2B84isJYJvEj6p5qcuxiP4e9jqp9UkE41PBwQBpwxPk0m%2Bt5eBBct11l7PWPX3QFm6Yxuw%2F0tasZKiLew%2FcQB0tTFdohEQGGj%2FgtmbRsOgdtYTQt95OvF%2FlmOdVwpwKXkfGGQLsAO0v360XGsMRjug3qXhnpf0axl1JDNA65IObbcKNPWZPX%2BF7kl52oWpka93U0x3y7lPfYh0RffrTiYLzWsJ%2FAhFNjhv0KQsqKUlNxZz5zisbe9%2F%2BaGdPiflu0WpbdDbV5slJUSA%2BH%2Fcw4MnuswY6pQHIDnK8FSFNQ3k5LGnGF0XnBzF9%2FS6GqxvjVop1bjYgsSDqJm45n17RXXg7FjdNsfcWGja7%2F%2B0S9uI86IijFEgHbpCr%2Fpvr%2Fpu5Gf5qZe%2F%2B%2Ba5qtj1KzoRxLllyHGdGlgXTJ7I1YXjEi3Uwc81q5EQQ4fNleqiH%2Bdt1M4h3yOuubgg27Te%2F0q4FBZW0AcL%2B740PAgKQ7I4kHyp1vrHMT485PzUbgLg%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIUYGXEWVE7%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T052624Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=efd8b5da16286451e03b8ba4ed8945b4947c29dce81f03a31336ccb420425c7f) |
カテゴリ |
簡易測定
茶
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