Abstract: To explore the new method of preparing slow-releasing microspheres of tea polyphenols, which will be useful for the applications of tea polyphenols. Through spray drying technology, tea polyphenols were microencapsulated by hydroxypropyl methylcellulose phthalate which is a biodegradable material. The microencapsulation process of tea polyphenols was optimized with orthogonal design L₉ (3⁴), the retention of tea polyphenols microspheres was used as the index. Results: A little emulsifier could increase the retention greatly , and the efficiency of SDS was better than PVA. The optimized conditions of tea polyphenols microencapsulation were that entrance temperature was 100℃, entrance speed was 6.25βml/min, proportion of tea polyphenols and wall material was 2:1, proportion of all solid maters was 3%. Using Hydroxypropyl methylcellulose phthalate as the wall material is feasible to prepare tea polyphenols microspheres by spray drying technology, and tea polyphenols microspheres had a slow-releasing efficiency.

Key words: spray drying, tea polyphenols, microsphere, hydroxypropyl methylcellulose phthalate