Determination of the best method for processing gambier liquid by-product [Uncaria gambir (hunter) roxb] as natural antioxidant sources

The study was conducted to determine the best gambier liquid by-product (GLB) processing methods based on antioxidant activity as natural antioxidant sources. The processing methods were A (ethyl acetate fractionation), B (oven drying) and C (freeze drying) methods. The observed variables were dry extract (using weighing method), tannin (using hide powder method), catechin (using SNI 01- 339-2000 method), total phenol (using folin ciocalteu reagents) and antioxidant activities (DPPH method) based on ICAO50. These antioxidant activities were compared with vitamin C as a positive control. The results indicated that the different processing methods significantly affected (P