Quantitative Real-Time Detection of Flavors During Fermentation by FD-ESI-MS

• Main Authors: Yi-Feng Lin, 林宜鋒
• Other Authors: Chang-Nan Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/36929459974413818944

碩士 === 朝陽科技大學 === 應用化學系碩士班 === 99 === Fermented dairy products are popular and nutritious foods due to the probiotics (lactic acid bacteria). The flavor produced during fermented milk products becomes an important topic for analytical chemists because the tastes that consumers care. Usually, fermentation procedure is monitored by the change of pH and the flavor analysis is usually performed by GC or GC/MS. Since these instruments only detect nonpolar compound,some details of the flavor ingredient are not available. Herein, by using a FD-ESI source, we have developed a method for real-time quantitative detection of the flavor during fermentation. The measured targets are lactic acid and acetic acid which are major components of the flavor and always make dramatic change of pH during the fermentation of milk. Ionization of the analyte in a FD-ESI source was achieved by reacting the gaseous analyte molecules with the charged solvent species generated by electrospray. The pure methanol was used for electrospray. Small amount of trifluoroacetic acid (10