NutriFOODchem Unit, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
J Agric Food Chem. 2011 Dec 28;59(24):12975-81. doi: 10.1021/jf203233s. Epub 2011 Nov 18.
Benzene may occur in foods due to the oxidative decarboxylation of benzoate in the presence of hydroxyl radicals. This study investigated factors influencing benzene formation in liquid model systems. The type of buffer, other sources of hydroxyl radical formation in food (photo oxidation of riboflavin and lipid oxidation), transition metal ion concentrations, and the inhibitory effect of antioxidants were tested in benzoate containing model systems. Regarding the hydroxyl radical sources tested, the highest benzene formation was observed in light exposed model systems containing ascorbic acid, Cu(2+), and riboflavin in Na-citrate buffer (1250 ± 131 μg kg(-1)). In practice, it seems that the combination ascorbic acid/transition metal ion remains the biggest contributor to benzene formation in food. However, the concentration of Cu(2+) influences significantly benzene formation in such a system with highest benzene yields observed for Cu(2+) 50 μM (1400 μg kg(-1)). The presence of antioxidants with metal chelation or reduction properties could prevent completely benzene formation.
苯可能由于在羟基自由基存在下，苯甲酸的氧化脱羧而存在于食物中。本研究调查了影响液体模型系统中苯形成的因素。在含有苯甲酸盐的模型系统中，测试了缓冲液的类型、食物中羟基自由基形成的其他来源（核黄素的光氧化和脂质氧化）、过渡金属离子浓度以及抗氧化剂的抑制作用。就所测试的羟基自由基来源而言，在含有抗坏血酸、Cu(2+)和核黄素的 Na-柠檬酸盐缓冲液（1250 ± 131 μg kg(-1)）中，暴露于光下的模型系统中观察到的苯生成量最高。在实践中，抗坏血酸/过渡金属离子的组合似乎仍然是食物中苯形成的最大贡献者。然而，Cu(2+)的浓度对该体系中苯的形成有显著影响，Cu(2+) 50 μM（1400 μg kg(-1)）时苯的生成量最高。具有金属螯合或还原性质的抗氧化剂的存在可以完全防止苯的形成。
