山楂原花青素的热降解动力学及稳定性研究

The degradation kinetics and the stability of procyanidins from Chinese hawthorn fruit

对山楂的主要原花青素（PC）成分EC、B2、C1进行了酸性条件热解动力学研究,考察了不同贮存、干制条件对PC稳定性的影响。结果表明：PC的热降解符合一级化学反应动力学模型,其降解速率常数与反应温度、分子聚合度密切相关,温度越高、聚合度越高其降解越快。在70%浆液浓度的山楂提取物中,20℃下这些PC成分的半衰期为73~177 d,40~60℃下半衰期为0.6~4 d。在20℃的山楂片中,PC成分的半衰期为150~376 d,40℃下半衰期为14~16 d,而在60℃下半衰期仅为1 d。经真空冷冻干燥这些PC成分的保存率为88%,热风干燥和自然干燥保存率分别为76%和25%。

The degradation kinetics of the procyanidins （PC） from hawthorn fruit under acidic conditions and their stability during the different storage and drying process were investigated. Results indicated that the thermal degradation of PC complied with the first-order reaction kinetic model. The higher the temperature and the degree of polymerization, the faster degradation. In the 70% hawthorn extract, the half-time of PC was 73~177 days at 20 ℃ and 0.6-4 days at 40-60 ℃. The half-time of PC in the hawthorn slice was 150~376 days at 20℃, 14~16 days at 40℃, and 1 day at 60 ℃. The preservation rate of PC was 88% at vacuum freeze-drying, 25% and 76% at hot air drying and natural drying respectively.