Limbo Sara, Torri Luisa, Piergiovanni Luciano
Department of Food Science and Microbiology, University of Milan, Via Celoria 2, 20133 Milan, Italy.
J Agric Food Chem. 2007 Jun 27;55(13):5238-45. doi: 10.1021/jf0634348. Epub 2007 Jun 1.
The aim of this work was to investigate the reaction kinetics of beta-carotene in an aqueous medium as a function of exposure to commercial lights (halogen and fluorescent sources) and oxygen partial pressures. The evolution of the pigment concentration, the changes in color, and the accumulation of a volatile compound (beta-ionone) were monitored during storage. The kinetics of degradation were mathematically modeled to compare the effects of lighting conditions and oxygen partial pressures. Lighting was also a critical variable in the presence of a low oxygen partial pressure (5 kPa), and in these conditions, the beta-carotene degraded completely during storage, even if more slowly than at 20 kPa of O2. The pigment degradation was correlated to illuminance and UVA irradiance values, but the different decay rates of the fluorescent lamps were explained by the differences in the blue region of the energy emission spectra. A halogen lamp gave minor negative effects on beta-carotene degradation.
这项工作的目的是研究β-胡萝卜素在水介质中的反应动力学，该动力学是暴露于商业照明（卤素灯和荧光光源）及氧气分压的函数。在储存过程中监测色素浓度的变化、颜色的改变以及挥发性化合物（β-紫罗兰酮）的积累。对降解动力学进行数学建模，以比较光照条件和氧气分压的影响。在低氧分压（5 kPa）的情况下，光照也是一个关键变量，在这些条件下，β-胡萝卜素在储存期间完全降解，尽管比在20 kPa氧气分压下降解得更慢。色素降解与照度和UVA辐照度值相关，但荧光灯不同的衰减率可由能量发射光谱蓝色区域的差异来解释。卤素灯对β-胡萝卜素降解产生的负面影响较小。
