叶黄素酯在强化面包制作和贮藏中的稳定性

Stability of Lutein Easters in Fortified Bread during Processing and Storage

通过将叶黄素酯水溶性微囊粉添加于面包中,考察面包和面、发酵、焙烤和贮藏过程中总叶黄素酯、总叶黄素及其异构体的变化情况,旨在监测叶黄素酯在强化面包制作和贮藏过程中的稳定性。结果表明:和面和发酵对叶黄素酯的降解影响不大,皂化测得的总叶黄素和全反式叶黄素保留率较高;烘烤引起面包皮和面包芯中叶黄素酯含量的明显降低,随之皂化测得的总叶黄素和全反式叶黄素保留率下降明显。叶黄素酯强化面包制作和贮藏过程中都伴有叶黄素异构体的不断生成和含量变化,和面过程中有少量的13-顺式和13’-顺式叶黄素生成,发酵过程有少量的9-顺式和9’-顺式叶黄素生成,焙烤过程面包皮和面包芯中13-顺式、13’-顺式、9-顺式和9’-顺式叶黄素含量显著累积增加,贮藏过程中面包皮和面包芯中的叶黄素酯、皂化测得的总叶黄素和全反式叶黄素含量,及叶黄素顺式异构体含量均略有下降。

Lutein exists in nature mostly in the form of lutein esters. Fortification of bread with lutein esters can improvedietary lutein intake. To investigate the stability of lutein esters in fortified bread during processing and subsequent storage,lutein and its stereoisomers as well as lutein esters were analyzed during dough processing, fermentation, baking and storage.The results showed that lutein esters were stable, and the retention rates of total lutein and trans-lutein after saponificationwere higher during dough processing and fermentation process. Baking caused a slight decrease in lutein esters in bread crustand core and a significant decline in the retention rates of total lutein and trans-lutein after saponification. The generationof cis-isomers was found during the whole processing and storage process of fortified bread. A small amount of 13-cis- and13’-cis-lutein were generated during dough making, and a small number of 9-cis- and 9’-cis-lutein were detected duringfermentation. Similarly, baking caused a significant increase in 13-cis-, 13’-cis-, 9-cis- and 9’-cis-lutein. The contents oflutein esters, lutein, trans-lutein and its cis-isomers declined slightly throughout the whole storage period.