Tinh b\u1ed9t l\u00e0 m\u1ed9t h\u1ee3p ch\u1ea5t h\u00f3a h\u1ecdc r\u1ea5t quan tr\u1ecdng trong \u0111\u1eddi s\u1ed1ng v\u00e0 lu\u00f4n hi\u1ec7n h\u1eefu trong cu\u1ed9c s\u1ed1ng c\u1ee7a ch\u00fang ta. V\u1edbi b\u00e0i vi\u1ebft h\u00f4m nay ch\u00fang ta c\u00f9ng t\u00ecm hi\u1ec3u v\u1ec1 tinh b\u1ed9t v\u00e0 s\u1ef1 h\u00ecnh th\u00e0nh c\u1ee7a tinh b\u1ed9t trong th\u1ef1c t\u1ebf nh\u01b0 th\u1ebf n\u00e0o<\/p>\n

I\/ T\u00ednh ch\u1ea5t v\u1eadt l\u00fd v\u00e0 tr\u1ea1ng th\u00e1i t\u1ef1 nhi\u00ean<\/h2>\n

\n
• Tinh b\u1ed9t l\u00e0 h\u1ee3p ch\u1ea5t r\u1eafn v\u00f4 \u0111\u1ecbnh h\u00ecnh c\u00f3 m\u00e0u tr\u1eafng v\u00e0 kh\u00f4ng tan trong n\u01b0\u1edbc ngu\u1ed9i.<\/li>\n
• Tinh b\u1ed9t tan trong n\u01b0\u1edbc n\u00f3ng t\u1eeb 65^{0<\/sup>C tr\u1edf l\u00ean th\u00ec tinh b\u1ed9t chuy\u1ec3n th\u00e0nh dung d\u1ecbch keo nh\u1edbt ta g\u1ecdi l\u00e0 h\u1ed3 tinh b\u1ed9t.<\/li>\n}
• Tinh b\u1ed9t l\u00e0 h\u1ee3p ch\u1ea5t c\u00f3 r\u1ea5t nhi\u1ec1u trong c\u00e1c lo\u1ea1i h\u1ea1t (nh\u01b0 g\u1ea1o, m\u00ec, ng\u00f4, \u0111\u1eadu…), c\u00e1c lo\u1ea1i c\u1ee7 (khoai, s\u1eafn…) v\u00e0 c\u00e1c lo\u1ea1i qu\u1ea3 (t\u00e1o, chu\u1ed1i, b\u00ed …). H\u00e0m l\u01b0\u1ee3ng tinh b\u1ed9t trong \u0111\u00f3 chi\u1ebfm kho\u1ea3ng 80% v\u00e0 trong ng\u00f4 chi\u1ebfm kho\u1ea3ng 70% v\u00e0 trong c\u1ee7 khoai t\u00e2y t\u01b0\u01a1i chi\u1ebfm kho\u1ea3ng 20%.<\/li>\n<\/ul>\n

  II\/ C\u1ea5u tr\u00fac ph\u00e2n t\u1eed<\/h2>\n

  \n
  • Tinh b\u1ed9t l\u00e0 h\u1ed7n h\u1ee3p c\u1ee7a 2 polisaccarit: amiloz\u01a1 v\u00e0 amilopectin. C\u1ea3 2 h\u1ee3p ch\u1ea5t \u0111\u1ec1u c\u00f3 CTPT l\u00e0 (C6<\/sub>H10<\/sub>O5<\/sub>)n<\/sub> trong \u0111\u00f3 h\u1ee3p ch\u1ea5t C6<\/sub>H10<\/sub>O5<\/sub> l\u00e0 g\u1ed1c \u03b1-glucoz\u01a1<\/li>\n<\/ul>\n

    1\/ Ph\u00e2n t\u1eed amiloz\u01a1<\/strong><\/h3>\n

    \n
    • Amiloz\u01a1 chi\u1ebfm kho\u1ea3ng 20 – 30% kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a tinh b\u1ed9t. Trong ph\u00e2n t\u1eed c\u1ee7a amiloz\u01a1 c\u00e1c g\u1ed1c \u03b1-glucoz\u01a1 \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi nhau b\u1edfi li\u00ean k\u1ebft \u03b1 – 1,4 – glicozit t\u1ea1o th\u00e0nh 1 chu\u1ed7i d\u00e0i v\u00e0 kh\u00f4ng ph\u00e2n nh\u00e1nh.<\/li>\n
    • Amiloz\u01a1 c\u00f3 s\u1ed1 ph\u00e2n t\u1eed kh\u1ed1i v\u00e0o kho\u1ea3ng 150.000 \u2212 600.000 (t\u01b0\u01a1ng \u1ee9ng v\u1edbi n kho\u1ea3ng 1000 \u2212 4000). Trong ph\u00e2n t\u1eed amiloz\u01a1 kh\u00f4ng du\u1ed7i th\u1eb3ng m\u00e0 n\u00f3 \u0111\u01b0\u1ee3c xo\u1eafn l\u1ea1i th\u00e0nh h\u00ecnh l\u00f2 xo.<\/li>\n
    • M\u1ed7i v\u00f2ng xo\u1eafn c\u1ee7a amiloz\u01a1 g\u1ed3m 6 g\u1ed1c glucoz\u01a1<\/li>\n<\/ul>\n

      <\/p>\n

      2\/ Ph\u00e2n t\u1eed amilopectin<\/h3>\n

      – Ph\u00e2n t\u1eed amilopectin chi\u1ebfm kho\u1ea3ng 70 – 80% kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a tinh b\u1ed9t.<\/p>\n

      – Amilopectin c\u00f3 c\u1ea5u t\u1ea1o d\u1ea1ng ph\u00e2n nh\u00e1nh. C\u1ee9 c\u00f3 kho\u1ea3ng 20 – 30% m\u1eaft x\u00edch \u03b1-glucoz\u01a1 \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi nhau b\u1edfi c\u00e1c li\u00ean k\u1ebft \u03b1-1,4-glicozit th\u00ec s\u1ebd t\u1ea1o th\u00e0nh 1 chu\u1ed7i. Do c\u00f3 th\u00eam c\u00e1c li\u00ean k\u1ebft t\u1eeb ph\u00e2n t\u1eed C_{1<\/sub> c\u1ee7a chu\u1ed7i n\u00e0y v\u1edbi ph\u00e2n t\u1eed C6<\/sub> c\u1ee7a chu\u1ed7i kia th\u00f4ng qua nguy\u00ean t\u1eed O (li\u00ean k\u1ebft \u03b1 – 1,6 – glicozit) n\u00ean chu\u1ed7i amilopectin \u00a0b\u1ecb ph\u00e2n nh\u00e1nh.<\/p>\n}

      <\/p>\n

      Amilopectin \u00a0c\u00f3 ph\u00e2n t\u1eed kh\u1ed1i v\u00e0o kho\u1ea3ng t\u1eeb 300.000\u22123.000.000 (t\u01b0\u01a1ng \u1ee9ng v\u1edbi n t\u1eeb 2000 – 200.000).<\/p>\n

      <\/p>\n

      Ch\u00fa \u00fd:<\/strong><\/p>\n

      – \u00a0Tinh b\u1ed9t c\u00f3 s\u1ed1 ph\u00e2n t\u1eed kh\u1ed1i kh\u00f4ng x\u00e1c \u0111\u1ecbnh l\u00e0 do n c\u00f3 s\u1ef1 bi\u1ebfn thi\u00ean trong 1 kho\u1ea3ng r\u1ed9ng<\/p>\n

      – \u00a0Tinh b\u1ed9t l\u00e0 1 lo\u1ea1i polime n\u00ean n\u00f3 kh\u00f4ng c\u00f3 2 t\u00ednh ch\u1ea5t sau:<\/p>\n

      + H\u00f2a tan \u0111\u01b0\u1ee3c Cu(OH)_{2<\/sub> (d\u00f9 cho trong tinh b\u1ed9t c\u00f3 nhi\u1ec1u nh\u00f3m \u2013OH li\u1ec1n k\u1ec1)<\/p>\n}

      + Tinh b\u1ed9t kh\u00f4ng c\u00f3 t\u00ednh kh\u1eed c\u1ee7a an\u0111ehit (m\u1eb7c d\u00f9 t\u1eadn c\u00f9ng c\u1ee7a ph\u00e2n t\u1eed tinh b\u1ed9t v\u1eabn c\u00f3 nh\u00f3m OH \u2013hemiaxetal).<\/p>\n

      \n
      • C\u00e1c nh\u00f3m \u2013 OH \u1edf trong tinh b\u1ed9t c\u00f3 kh\u1ea3 n\u0103ng ph\u1ea3n \u1ee9ng t\u1ea1o ra este nh\u01b0 glucoz\u01a1.<\/li>\n<\/ul>\n

        III\/ T\u00ednh ch\u1ea5t h\u00f3a h\u1ecdc c\u1ee7a tinh b\u1ed9t<\/h2>\n

        1\/ Ph\u1ea3n \u1ee9ng th\u1ee7y ph\u00e2n c\u1ee7a tinh b\u1ed9t<\/h3>\n

        a) Tinh b\u1ed9t th\u1ee7y ph\u00e2n nh\u1edd ch\u1ea5t x\u00fac t\u00e1c l\u00e0 axit<\/strong><\/p>\n

        Ta c\u00f3 dung d\u1ecbch tinh b\u1ed9t kh\u00f4ng tham gia ph\u1ea3n \u1ee9ng tr\u00e1ng b\u1ea1c. Sau khi ta \u0111un n\u00f3ng dung d\u1ecbch tinh b\u1ed9t v\u1edbi axit v\u00f4 c\u01a1 lo\u00e3ng ta thu \u0111\u01b0\u1ee3c dung d\u1ecbch c\u00f3 kh\u1ea3 n\u0103ng tham gia ph\u1ea3n \u1ee9ng tr\u00e1ng b\u1ea1c.<\/p>\n

        Nguy\u00ean nh\u00e2n x\u1ea3y ra hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y l\u00e0 do tinh b\u1ed9t s\u1ebd b\u1ecb th\u1ee7y ph\u00e2n ho\u00e0n to\u00e0n t\u1ea1o ra glucoz\u01a1<\/p>\n

        <\/p>\n

        b) Tinh b\u1ed9t th\u1ee7y ph\u00e2n nh\u1edd ch\u1ea5t x\u00fac t\u00e1c l\u00e0 enzim<\/strong><\/p>\n

        Ta c\u00f3 tinh b\u1ed9t c\u0169ng c\u00f3 ph\u1ea3n \u1ee9ng th\u1ee7y ph\u00e2n x\u1ea3y ra nh\u1edd 1 s\u1ed1 enzim.<\/p>\n

        Nh\u1edd c\u00e1c enzim \u03b1\u2212 v\u00e0 \u03b2\u2212 amilaza (c\u00f3 \u1edf trong n\u01b0\u1edbc b\u1ecdt v\u00e0 c\u00f3 trong m\u1ea7m l\u00faa) m\u00e0 tinh b\u1ed9t b\u1ecb th\u1ee7y ph\u00e2n t\u1ea1o th\u00e0nh \u0111extrin (C_{6<\/sub>H10<\/sub>O5<\/sub>)x <\/sub>(x<n) r\u1ed3i t\u1ea1o th\u00e0nh mantoz\u01a1 v\u00e0 mantoz\u01a1 khi b\u1ecb th\u1ee7y ph\u00e2n s\u1ebd t\u1ea1o th\u00e0nh glucoz\u01a1 nh\u1edd c\u00e1c enzim mantaza<\/p>\n}

        2\/ Tinh b\u1ed9t c\u00f3 ph\u1ea3n \u1ee9ng m\u00e0u v\u1edbi dung d\u1ecbch iot<\/h3>\n

        Th\u00ed nghi\u1ec7m:<\/strong><\/p>\n

        Ta nh\u1ecf dung d\u1ecbch iot v\u00e0o trong \u1ed1ng nghi\u1ec7m c\u00f3 ch\u1ee9a dung d\u1ecbch h\u1ed3 tinh b\u1ed9t ho\u1eb7c ta nh\u1ecf v\u00e0o m\u1eb7t c\u1eaft c\u1ee7a 1 c\u1ee7 khoai lang.<\/p>\n

        Hi\u1ec7n t\u01b0\u1ee3ng x\u1ea3y ra:<\/strong><\/p>\n

        Dung d\u1ecbch c\u1ee7a h\u1ed3 tinh b\u1ed9t ch\u1ee9a trong \u1ed1ng nghi\u1ec7m v\u00e0 m\u1eb7t c\u1eaft c\u1ee7 khoai lang \u0111\u1ec1u c\u00f3 m\u00e0u xanh t\u00edm.<\/p>\n

        Khi ta \u0111un n\u00f3ng th\u00ec m\u00e0u xanh t\u00edm n\u00e0y bi\u1ebfn m\u1ea5t v\u00e0 khi \u0111\u1ec3 ngu\u1ed9i th\u00ec m\u00e0u xanh t\u00edm l\u1ea1i xu\u1ea5t hi\u1ec7n.<\/p>\n

        Gi\u1ea3i th\u00edch hi\u1ec7n t\u01b0\u1ee3ng:<\/strong><\/p>\n

        Do ph\u00e2n t\u1eed c\u1ee7a tinh b\u1ed9t s\u1ebd h\u1ea5p th\u1ee5 iot v\u00e0 t\u1ea1o ra m\u00e0u xanh t\u00edm.<\/p>\n

        Khi ta \u0111un n\u00f3ng th\u00ec iot trong ph\u00e2n t\u1eed b\u1ecb gi\u1ea3i ph\u00f3ng ra kh\u1ecfi ph\u00e2n t\u1eed tinh b\u1ed9t v\u00e0 l\u00e0m m\u1ea5t \u0111i m\u00e0u xanh t\u00edm \u0111\u00f3.<\/p>\n

        Khi \u0111\u1ec3 ngu\u1ed9i dung d\u1ecbch th\u00ec iot b\u1ecb h\u1ea5p th\u1ee5 l\u1ea1i l\u00e0m cho dung d\u1ecbch l\u1ea1i c\u00f3 m\u00e0u xanh t\u00edm. V\u1edbi ph\u1ea3n \u1ee9ng n\u00e0y \u0111\u01b0\u1ee3c ta d\u00f9ng \u0111\u1ec3 nh\u1eadn bi\u1ebft tinh b\u1ed9t b\u1eb1ng iot v\u00e0 ng\u01b0\u1ee3c tr\u1edf l\u1ea1i<\/p>\n

        IV\/ S\u1ef1 chuy\u1ec3n h\u00f3a c\u1ee7a tinh b\u1ed9t \u1edf trong c\u01a1 th\u1ec3<\/h2>\n

        Tinh b\u1ed9t c\u00f3 trong c\u00e1c lo\u1ea1i l\u01b0\u01a1ng th\u1ef1c l\u00e0 1 trong nh\u1eefng lo\u1ea1i th\u1ee9c \u0103n c\u01a1 b\u1ea3n c\u1ee7a con ng\u01b0\u1eddi. Khi ch\u00fang ta \u0103n th\u00ec tinh b\u1ed9t b\u1ecb th\u1ee7y ph\u00e2n nh\u1edd c\u00e1c enzim amilaza c\u00f3 \u1edf trong th\u00e0nh ph\u1ea7n c\u1ee7a n\u01b0\u1edbc b\u1ecdt t\u1ea1o th\u00e0nh \u0111extrin, r\u1ed3i chuy\u1ec3n th\u00e0nh mantoz\u01a1. Trong ru\u1ed9t th\u00ec c\u00e1c enzim mantaza gi\u00fap vi\u1ec7c th\u1ee7y ph\u00e2n c\u00e1c mantoz\u01a1 th\u00e0nh glucoz\u01a1. V\u00e0 glucoz\u01a1 n\u00e0y \u0111\u01b0\u1ee3c h\u1ea5p th\u1ee5 th\u00f4ng qua th\u00e0nh mao c\u1ee7a ru\u1ed9t \u0111i v\u00e0o m\u00e1u.<\/p>\n

        Trong m\u00e1u th\u00ec n\u1ed3ng \u0111\u1ed9 glucoz\u01a1 lu\u00f4n kh\u00f4ng \u0111\u1ed5i chi\u1ebfm kho\u1ea3ng 0,1% . C\u00f2n l\u01b0\u1ee3ng glucoz\u01a1 d\u01b0 th\u1eeba \u0111\u01b0\u1ee3c chuy\u1ec3n v\u1ec1 ch\u1ee9a trong gan: t\u1ea1i \u0111\u00e2y th\u00ec glucoz\u01a1 h\u1ee3p th\u00e0nh c\u00e1c enzim v\u00e0 t\u1ea1o th\u00e0nh glicogen (hay c\u00f2n g\u1ecdi l\u00e0 tinh b\u1ed9t \u0111\u1ed9ng v\u1eadt) \u0111\u01b0\u1ee3c d\u1eef tr\u1eef trong c\u01a1 th\u1ec3.<\/p>\n

        Khi m\u00e0 n\u1ed3ng \u0111\u1ed9 c\u1ee7a glucoz\u01a1 c\u00f3 trong m\u00e1u b\u1ecb gi\u1ea3m xu\u1ed1ng d\u01b0\u1edbi m\u1ee9c 0,1% th\u00ec glicogen \u1edf trong gan s\u1ebd b\u1ecb th\u1ee7y ph\u00e2n th\u00e0nh t\u1ea1o glucoz\u01a1 v\u00e0 th\u00f4ng qua \u0111\u01b0\u1eddng m\u00e1u chuy\u1ec3n \u0111\u1ebfn c\u00e1c t\u1ea5t c\u1ea3 c\u00e1c m\u00f4 trong c\u01a1 th\u1ec3. T\u1ea1i c\u00e1c m\u00f4 n\u00e0y th\u00ec glucoz\u01a1 s\u1ebd b\u1ecb oxi h\u00f3a ch\u1eadm th\u00f4ng qua c\u00e1c ph\u1ea3n \u1ee9ng ph\u1ee9c t\u1ea1p nh\u1edd c\u00e1c enzim t\u1ea1o th\u00e0nh CO_{2<\/sub> v\u00e0 H2<\/sub>O, \u0111\u1ed3ng th\u1eddi n\u00f3 gi\u1ea3i ph\u00f3ng ra n\u0103ng l\u01b0\u1ee3ng \u0111\u1ec3 c\u01a1 th\u1ec3 ho\u1ea1t \u0111\u1ed9ng.<\/p>\n}

        S\u1ef1 chuy\u1ec3n h\u00f3a c\u1ee7a tinh b\u1ed9t \u1edf trong c\u01a1 th\u1ec3 \u0111\u01b0\u1ee3c bi\u1ec3u di\u1ec5n d\u01b0\u1edbi d\u1ea1ng s\u01a1 \u0111\u1ed3 sau:<\/p>\n

        <\/p>\n

        V\/ S\u1ef1 t\u1ea1o th\u00e0nh tinh b\u1ed9t \u1edf trong c\u00e2y xanh<\/h2>\n

        Tinh b\u1ed9t s\u1ebd \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh trong c\u00e1c c\u00e2y xanh t\u1eeb kh\u00ed CO_{2<\/sub> v\u00e0 H2<\/sub>O \u00a0d\u01b0\u1edbi t\u00e1c d\u1ee5ng c\u1ee7a \u00e1nh s\u00e1ng m\u1eb7t tr\u1eddi. Kh\u00ed CO2 <\/sub>trong kh\u00f4ng kh\u00ed \u0111\u01b0\u1ee3c l\u00e1 c\u00e2y h\u1ea5p th\u1ee5 v\u00e0 n\u01b0\u1edbc \u0111\u01b0\u1ee3c h\u00fat t\u1eeb \u0111\u1ea5t th\u00f4ng qua r\u1ec5 c\u00e2y. Ch\u1ea5t di\u1ec7p l\u1ee5c (clorophin) trong l\u00e1 c\u00e2y h\u1ea5p th\u1ee5 n\u0103ng l\u01b0\u1ee3ng \u00e1nh s\u00e1ng m\u1eb7t tr\u1eddi.<\/p>\n}

        Qu\u00e1 tr\u00ecnh t\u1ea1o th\u00e0nh tinh b\u1ed9t c\u1ee7a c\u00e2y xanh nh\u01b0 v\u1eady \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 qu\u00e1 tr\u00ecnh quang h\u1ee3p. Qu\u00e1 tr\u00ecnh n\u00e0y x\u1ea3y ra r\u1ea5t ph\u1ee9c t\u1ea1p qua r\u1ea5t nhi\u1ec1u giai \u0111o\u1ea1n, trong \u0111\u00f3 c\u00f3 1 giai \u0111o\u1ea1n t\u1ea1o th\u00e0nh glucoz\u01a1.<\/p>\n

        Qu\u00e1 tr\u00ecnh n\u00e0y \u0111\u01b0\u1ee3c vi\u1ebft b\u1eb1ng ph\u01b0\u01a1ng tr\u00ecnh h\u00f3a h\u1ecdc nh\u01b0 sau:<\/p>\n

        <\/p>\n

        Hi v\u1ecdng v\u1edbi b\u00e0i vi\u1ebft tr\u00ean c\u00e1c b\u1ea1n c\u00f3 th\u00eam nh\u1eefng ki\u1ebfn th\u1ee9c b\u1ed5 \u00edch v\u1ec1 tinh b\u1ed9t<\/p>\n","protected":false},"excerpt":{"rendered":"

        Tinh b\u1ed9t l\u00e0 m\u1ed9t h\u1ee3p ch\u1ea5t h\u00f3a h\u1ecdc r\u1ea5t quan tr\u1ecdng trong \u0111\u1eddi s\u1ed1ng v\u00e0 lu\u00f4n hi\u1ec7n h\u1eefu trong cu\u1ed9c s\u1ed1ng c\u1ee7a ch\u00fang ta. V\u1edbi b\u00e0i vi\u1ebft h\u00f4m nay ch\u00fang… <\/p>\n","protected":false},"author":9,"featured_media":8486,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[471,450],"tags":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/posts\/8479"}],"collection":[{"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/comments?post=8479"}],"version-history":[{"count":0,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/posts\/8479\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/media\/8486"}],"wp:attachment":[{"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/media?parent=8479"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/categories?post=8479"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/onthitot.com\/wp-json\/wp\/v2\/tags?post=8479"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}