明胶60Co-γ辐照灭菌过程中的水分和氧气效应
Effect of water and oxygen on gelatin crosslinking during process of 60Co-γ irradiation
-
摘要: 将含水量0%80%的明胶分别采用透气和真空包装,并经60Co-γ辐射8kGy后,测定辐照前后特性粘度、凝胶强度、拉伸参数的变化,并采用扫描电镜(SEM)、差示扫描量热仪(DSC)表征了材料的结构,研究水分和氧气对明胶辐照交联的影响。结果表明,随着明胶辐照灭菌时水分含量的增加,特性黏度和凝胶强度持续下降;SEM图样品表面形貌由颗粒状转变为多层网络结构;DSC热流图中熔胶峰由28℃左右的单峰转变20℃和40℃左右的双峰,凝胶峰温升高;明胶膜的断裂伸长率随含水量的增加而下降,其变化范围为142.33%343.5%;真空包装明胶辐照后交联程度比透气包装严重。结论:水分含量与明胶辐射交联呈正效应,而氧气与辐射交联呈负效应。控制水分含量和有氧辐照可减少辐照灭菌过程中的交联导致的明胶品质下降的问题。Abstract: Gelatin with 0%80% water was packaged respectively by oxygen permeable and vacuum materials and irradiated for 8kGy by60Co-γ. The relationship of moisture and oxygen content with gelatin irradiation crosslinking were analyzed by methods including intrinsic viscosity, texture analyzer, scanning electron microscope photographs technology (SEM) and differential scanning calorimetry (DSC) . Results showed that with the increase of gelatin water content, the intrinsic viscosity and gel strength decreased. The irradiated gelatin appeared network structure in SEM spectrum and two melting peakes and the temperatures were 20℃and 40℃ in DSC spectrum. The gelling temperature increased with the water content, but The crosslinking degree of irradiated gelatin by vacuum packaged had the stronger crosslinking reaction than the oxygen permeable packed one.It was suggested that there was a positive effect that existed between the crosslinking degree and water content, but negative effect with oxygen content. The gelatin quality would be ensured by controlling lower moisture and sufficient oxygen content in the gelatin before irradiating.