Characteristics of glucomannan of Porang Flour (Amorphophallus oncophyllus) with Various Chemical Extraction Methods Tety Desrita Handayani, agustina agustina, Eni Harmayani, Yudi Pranoto Jurnal Sains dan Teknologi Pangan Vol. 8 No. 3 2023 DOI 10.33772/jstp.v8i3.38413