[The method of boiling gelatin in Qimin Yaoshu and its contemporary value].

Qimin Yaoshu(, Essential Techniques for the Welfare of the People), written in the Northern Wei Dynasty, had a specific record of process of boiling down gelatin, it involved 12 steps. Comparing with the methods of later generations, we find that the main differences lie in 6 aspects: shaving hair, adding accessories, duration and degree of heating for gel-forming, preventing gelatin from scorching, drying method, checking water quality. Especially, it is considered that the experience of no hair shaving and excipients adding is of great reference value to the cooking methods of modern donkey-hide gelatin and ox-hide gelatin.成书于北魏时期的《齐民要术》有关于煮胶工艺的详细记载，共12个步骤。与后世的方法进行比较发现最主要的区别在于削毛、添加辅料、成胶火候、防焦糊法、干燥法、水质等6方面。尤其是削毛无益、不添加辅料及成胶火候的经验，对于现代阿胶、黄明胶的煮制方法有重要的参考价值。.