aplha-Dicarbonyl compounds are highly reactive substances found in foods and beverages. They are formed during processing, cooking and prolonged storage as end products of lipid peroxidation, microorganism metabolites, and caramelization or Maillard reaction products. Precise and accurate determination of their content in foods is important, because they exert both positive and negative effects on human health, even at low doses. The method most frequently applied to determine alpha-dicarbonyl compounds in foods and beverages involves their derivatization with 1,2- diaminobenzene, to obtain specific quinoxaline derivatives that can be detected by HPLC or GC. In the literature derivatization conditions vary widely, particularly the pH of the medium and temperature, without considering that alpha-dicarbonyl compounds can form as glucose and fructose fragmentation products. Our data demonstrate that derivatization conditions critically affect the fragmentation process in sugar-rich matrices. In this work we tested a range of derivatization conditions to find the combination that would allow accurate and precise determination of alpha-dicarbonyl compounds sugar-rich matrices. Formation of alpha-dicarbonyl compounds due to glucose and fructose fragmentation was found to be avoided by using an acidic medium (pH 3.0) at low temperature (25 °C) while allowing a derivatization yield close to 100% for the alpha-dicarbonyl compounds considered (methylglyoxal and diacetyl). Analysis of four types of red wine having different sugar contents (two table wines and two dessert wines) confirmed that these conditions prevent alpha-dicarbonyl compound overestimation as well as false positive results.
Determination of alpha-dicarbonyl compounds in foods with a high content of free sugars / Daglia, Maria; Papetti, Adele; Mascherpa, Dora; Sordelli, Barbara; Gazzani, Gabriella. - 1:(2009), pp. 123-123. (Intervento presentato al convegno 13th International Meeting on Recent Developments in Pharmaceutical Analysis (RDPA 2009) tenutosi a Milano nel 9-12 settembre 2009).
Determination of alpha-dicarbonyl compounds in foods with a high content of free sugars
DAGLIA, MARIA;
2009
Abstract
aplha-Dicarbonyl compounds are highly reactive substances found in foods and beverages. They are formed during processing, cooking and prolonged storage as end products of lipid peroxidation, microorganism metabolites, and caramelization or Maillard reaction products. Precise and accurate determination of their content in foods is important, because they exert both positive and negative effects on human health, even at low doses. The method most frequently applied to determine alpha-dicarbonyl compounds in foods and beverages involves their derivatization with 1,2- diaminobenzene, to obtain specific quinoxaline derivatives that can be detected by HPLC or GC. In the literature derivatization conditions vary widely, particularly the pH of the medium and temperature, without considering that alpha-dicarbonyl compounds can form as glucose and fructose fragmentation products. Our data demonstrate that derivatization conditions critically affect the fragmentation process in sugar-rich matrices. In this work we tested a range of derivatization conditions to find the combination that would allow accurate and precise determination of alpha-dicarbonyl compounds sugar-rich matrices. Formation of alpha-dicarbonyl compounds due to glucose and fructose fragmentation was found to be avoided by using an acidic medium (pH 3.0) at low temperature (25 °C) while allowing a derivatization yield close to 100% for the alpha-dicarbonyl compounds considered (methylglyoxal and diacetyl). Analysis of four types of red wine having different sugar contents (two table wines and two dessert wines) confirmed that these conditions prevent alpha-dicarbonyl compound overestimation as well as false positive results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
