Produksi Kolagen dari Membran Cangkang Telur Ayam dan Analisis Kandungan Hidroksiprolin Menggunakan Kromatografi Cair Kinerja Tinggi Detektor Fluoresensi = Collagen Production From Chicken's Eggshell Membrane and Analysis of its Hydroxyproline Content Using High Performance Liquid Chromatography-Fluorescence Detector