ABSTRACT
Carbohydrates widely occur in foodstuffs. Knowledge of their qualitative and quantitative distribution in fruits, vegetables, honey, alcoholic and nonalcoholic drinks, dairy products, meat and meat derivatives, and other natural matrices is essential because they are involved in very important characteristics, such as avor, maturity, quality, authenticity, storage conditions (sugars in their raw state diminish rapidly during storage at room temperature), and so on. Therefore, the qualitative and quantitative determination of carbohydrates in foods by high-performance liquid chromatography (HPLC) has been dealt with and
7.1 Introduction .................................................................................................................................. 233 7.1.1 Why the Determination of Carbohydrates ...................................................................... 235 7.1.2 Properties of Carbohydrates ............................................................................................ 235 7.1.3 HPLC versus Other Analytical Techniques .................................................................... 236
7.2 Sample Preparation ...................................................................................................................... 237 7.2.1 Extraction ........................................................................................................................ 237 7.2.2 Cleanup ............................................................................................................................ 238
7.2.2.1 Clarifying Agents ............................................................................................ 239 7.2.2.2 Solvent Precipitation ........................................................................................ 239 7.2.2.3 Ion Exchange .................................................................................................... 239 7.2.2.4 Sep-Pak Cartridges .......................................................................................... 239 7.2.2.5 Guard Columns ................................................................................................ 240 7.2.2.6 Column Switching ........................................................................................... 240
7.3 Separation Techniques: HPLC Columns ..................................................................................... 240 7.3.1 Gel Filtration ................................................................................................................... 240 7.3.2 Ion-Exchange Chromatography ....................................................................................... 241 7.3.3 Partition Chromatography ............................................................................................... 242 7.3.4 Adsorption Chromatography ........................................................................................... 242
7.4 Detection Systems ........................................................................................................................ 243 7.4.1 Derivatization Techniques ............................................................................................... 243 7.4.2 Refractive Index Detection .............................................................................................. 244 7.4.3 Ultraviolet Detection ....................................................................................................... 244 7.4.4 Evaporative Light-Scattering Detection .......................................................................... 244 7.4.5 Pulsed Amperometric Detection ..................................................................................... 245 7.4.6 Other Detection Systems ................................................................................................. 246
7.5 Applications in Foods .................................................................................................................. 246 7.6 Conclusions .................................................................................................................................. 249 References .............................................................................................................................................. 249
TABLE 7.1
Most Important Food Carbohydrates
TABLE 7.2
Summary of Most Important Food Polysaccharides
reviewed by several authors, either in the form of books or chapters of books or as scientic papers, most notably in the current decade [1-6].
