Food Analysis Chromatography
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Scanning Electron Microscopy (SEM) is used for inspecting topographies of specimens at very high magnifications, with magnifications that can go to more than $300,000$ X, while applications require magnifications of less than $3,000$ X. A beam of electrons is focused on a spot volume of the specimen, resulting in the transfer of energy to the spot. These bombarding electrons dislodge electrons from the specimen itself, known as __________ electrons.

secondary

Transmission Electron Microscopy (TEM) is analogous to a slide projector.

True

What is the purpose of using maggots on wounds?

Clean wounds by feeding on dead tissue and leaving healthy tissue untouched. Their saliva contains anti-bacterial chemicals.

What is the primary function of Scanning Electron Microscopy (SEM)?

<p>Inspecting topographies of specimens at very high magnifications</p> Signup and view all the answers

What is the purpose of Transmission Electron Microscopy (TEM)?

<p>Viewing detailed internal structures of specimens</p> Signup and view all the answers

Study Notes

Chromatography Detectors

  • Ultraviolet-visible spectrometer is commonly used in chromatography to detect and quantify separated components.

Sample Preparation Techniques

  • Extraction, centrifugation, and filtration are commonly used sample preparation techniques prior to chromatography in food analysis.

Chromatography Types

Amino Acid Analysis

  • Ion exchange chromatography is commonly used for separating and analyzing amino acids in food.

Sugar Analysis

  • High performance liquid chromatography is commonly used for separating and analyzing sugars in food.

Microstructure

  • Maggots of the bluebottle fly (Protophormia sp.) are used medicinally to clean wounds by feeding on dead tissue and leaving healthy tissue untouched.
  • The maggots' saliva contains anti-bacterial chemicals, maintaining sterility in the wound area.
  • They are used to treat diabetic ulcers on the feet and other deep wounds away from organs or body cavities.

SEM and TEM

  • Scanning Electron Microscopy (SEM) is used to inspect topographies of specimens at high magnifications (up to 300,000 X).
  • SEM applications often require magnifications of less than 3,000 X.
  • SEM works by focusing a beam of electrons onto a specimen, dislodging secondary electrons, which are then collected and translated into a signal, producing an image of the topography.

Transmission Electron Microscopy (TEM)

  • TEM is analogous to a slide projector.
  • In a conventional TEM, a thin specimen is irradiated with an electron beam, and electrons are emitted from the electron gun and illuminate the specimen through a condenser lens system.
  • The objective lens forms an image or diffraction pattern of the specimen, which is then magnified and viewed on a fluorescent screen or recorded digitally.
  • Acceleration voltage (up to 3 MV) determines the resolution of the microscope.

Types of TEM

  • Conventional Transmission Electron Microscopy
  • High Resolution Electron Microscopy
  • Analytical Electron Microscopy
  • Energy-Filtering Electron Microscopy
  • High Voltage Electron Microscopy
  • Dedicated Scanning Transmission Electron Microscopy

Microstructure

  • Maggots of the bluebottle fly (Protophormia sp.) are used medicinally to clean wounds by feeding on dead tissue and leaving healthy tissue untouched.
  • The maggots' saliva contains anti-bacterial chemicals, maintaining sterility in the wound area.
  • They are used to treat diabetic ulcers on the feet and other deep wounds away from organs or body cavities.

SEM and TEM

  • Scanning Electron Microscopy (SEM) is used to inspect topographies of specimens at high magnifications (up to 300,000 X).
  • SEM applications often require magnifications of less than 3,000 X.
  • SEM works by focusing a beam of electrons onto a specimen, dislodging secondary electrons, which are then collected and translated into a signal, producing an image of the topography.

Transmission Electron Microscopy (TEM)

  • TEM is analogous to a slide projector.
  • In a conventional TEM, a thin specimen is irradiated with an electron beam, and electrons are emitted from the electron gun and illuminate the specimen through a condenser lens system.
  • The objective lens forms an image or diffraction pattern of the specimen, which is then magnified and viewed on a fluorescent screen or recorded digitally.
  • Acceleration voltage (up to 3 MV) determines the resolution of the microscope.

Types of TEM

  • Conventional Transmission Electron Microscopy
  • High Resolution Electron Microscopy
  • Analytical Electron Microscopy
  • Energy-Filtering Electron Microscopy
  • High Voltage Electron Microscopy
  • Dedicated Scanning Transmission Electron Microscopy

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Description

This quiz covers various aspects of chromatography in food analysis, including detectors, sample preparation techniques, and types of chromatography.

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