Stability of vitamin A, E, C and thiamine during storage of different powdered enteral formulas
Yang Hong, Lili Xu, Ling Hou, Tong Cheng Xu, Shu Hong Ye
Abstract
In this study, two different kinds of commercial enteral formulas were selected to evaluate the changes of vitamin A, E, C and thiamine during the different storage conditions of different temperature and relative humidity (60 ± 1 °C, 60 ± 5% for 5 and 10 days; 37 ± 1 °C, 75 ± 5% for 1, 2, 3, 5 and 6 months; 25 ± 1 °C, 60 ± 5% for 3, 6, 9, 12, 18 and 24 months). The results showed that as the temperature or time increased, the content of vitamin A, E and thiamine was gradually decreased whilst the level of vitamin C remained stable. The vitamins exhibited more stability at the storage of 25 ± 1 °C, RH 60 ± 5%. Vitamin A and thiamine decreased more in the polymeric formula (EFA) than that in the oligomeric formula (EFB), while, vitamin E decreased less in EFA than that in EFB. The kinetics of vitamin A, E and thiamine degradation during storage followed first order kinetic equations. Furthermore, the final levels of vitamins were higher than the minimum level recommended by legislation.