热加工过程淀粉基膜材结构变化和增塑剂迁移研究

目的]研究不同加热方式下,淀粉基膜材的结构变化和增塑剂迁移情况,为新型淀粉基膜材在食品包装中的应用提供参考。方法]以蒸馏水体系为热加工介质,采用沸水加热和微波加热,对淀粉基膜材进行热加工处理并分析加热过程中膜材表层增塑剂迁移、总迁移及膜材基体质量和结构变化。结果]沸水加热和微波加热均加剧了淀粉基膜材表面增塑剂的迁移,淀粉高分子片段溶出,膜材内部产生高分子聚集,促使膜材总体迁移增大;当增塑剂含量较低时,2种热加工处理后的膜材断面形成了更加明显的孔洞结构。另外,相比于沸水加热,微波加热较高的瞬时功率促使膜材表层增塑剂迁移、总迁移程度更大。结论]不同的热传递模式导致淀粉基膜材结构变化与分子迁移存在差异。

Structure Changes and Plasticizer Migration of Starch-based Films during Thermal Process

Objective] To provide references for practical application of starch-based food packaging materials,migration behavior and structure changes were studied in starch-based films treated by thermal processing.Method]Boiling water,microwave and distilled water were chosen to be the heating method and food simulant system,respectively,modern technologies were prepared to investigate the migration of surface plasticizer,total migration,changes on the mass of matrix and morphology of fractured surface of starch-based films.Result] The results indicated that thermal processing promoted plasticizer migration of the surface layer,dissolution and aggregation of starch molecular accelerated the total migration.Moreover,more pore structures were in the starch-based films with lower plasticizer content.Compared with boiling water treatment,plasticizer migration and total migration were more severe by microwave.Conclusion] Based on the results above,the structure changes and molecular migration in the starch-based film were diverse with two thermal deliveries.