Résumé
Objective To determine and compare the contents of free total organic acids in Pinellia ternata and its processed products.Methods Back potentiometric titration was employed to determine the contents of free total organic acids in Pinellia ternata and its processed products.Results The contents of free total organic acids in three batches of Pinellia ternata and its processed products were determined.The contents of free total organic acids in prepared rhizoma pinelliae was higher than that of the crude drug.The recovery was 95.20% and RSD was 1.81%.Conclusion This method were simple,accurate and can be used to estimate the quality of Pinellia ternata and its processed products(prepared with potash alum and juice of rhizima zingiber or with just potash alum).