Abstract: Objective: To explore the sugar composition of pectin extracted from Premna microphylla leaves and its effect on the coagulation of Fairy Tofu, a jelly-like food prepared from Premna microphylla leaves and coagulant. Methods: Pectin was obtained as a creamy yellowish precipitate from Premna microphylla leaf juice by sulfuric acid hydrolysis, ethanol precipitation, TCA-chloroform deproteinization, ammonia-ethanol decolorization and 95% ethanol precipitation. After further hydrolysis with sulfuric acid, the precipitate (pectin) was analyzed by silica gel G thin-layer chromatography for saccharide composition. In addition, its pH, soluble pectin content and degree of esterification were determined and its protein content was measured by biuret protein assay. Also, we analyzed the effects of coagulant type (synthetic coagulant and plant ash) and dosage on the coagulation of the pectin for Fairy Tofu production. Results: The pectin extract contained 78.24% saccharides, mainly glucose, fructose and D-mannose and 21.76% protein. It had high water binding capacity and a degree of esterification of 74.6% and its properties were close to international quality standards. The Fairy Tofu prepared from it revealed a degree of coagulation higher than 100. Conclusion: The preparation of Fairy Tofu from Premna microphylla leaves is based on the simultaneous interactions of pectin with calcium and magnesium ions.

Key words: Premna microphylla, pectin, physical and chemical properties, preparation, leaf tofu