This experiment was conducted to compare the tannin content of four sorghum varieties using six quantitative methods of tannin determination. A completely randomized design in a 4 x 6 (variety x method) factorial arrangement with four replicates was used, where: T1: Folin Denis (Folin Denis reagent reflux); T2: Folin Denis (water reflux); T3: Folin Denis (water reflux followed by filtration); T4: Lowental, T5: Vanilin cloridric acid of Burns, and T6: Vanilin cloridric acid modified of Burns. The highest tannin content was observed when determined by Burns methods and the lowest content by Lowental method. The results showed a wide variability among the methods used to determine tannin. By the laboratory practice, the Folin Denis method - CNPSA may be the most recomended method.
Burns; Folin Denis; Lowental; sorghum