Comparative studies of konjac flours extracted from Amorphophallus guripingensis and Amorphophallus rivirei: Based on chemical analysis and rheology

• Amorphophallus guripingensis is developed as a promising resource for extracting konjac powder.
• Rheological properties of refined A. guripingensis flour showed sensitive pH-response.
• Lower gel forming temperature of A. guripingensis flour extends its application range.

Konjac glucomannan (KGM) has been widely used in food industry, which is commonly extracted from Amorphophallus rivirei. In this paper, Amorphophallus guripingensis was found to be another good resource of extracted KGM. The comparative studies, based on chemical composition analysis and rheological measurements, between those two different resources were investigated. Results showed that refined A. guripingensis flour (AGF) contained 61.35% KGM, which was lower than that of refined ARF (72.80%). But, the viscosity-increased speed of AGF was faster than ARF. To be specific, even the viscosity of 3.5 wt% AGF solution was half of ARF, while they had similar viscosity values at a concentration of 4.5 wt%. Besides, viscosity change of the refined AGF with pH was more pronounced under strong acid condition. Meanwhile, thermo-gelling temperature of 4.0 wt% AGF solution was 85 °C, lower than that of ARF. These results demonstrated that AGF solutions were sensitive to processing factors, such as pH and temperature as compared to A. rivirei. Those properties endows AGF more valuable applications in food industry and it has great potential to be a pH-sensitive matrix.

Figure optionsDownload as PowerPoint slide