Abstract
[Objective] This study aimed to explore the potential use of overgrown, non-commercial grade Auricularia polytricha (wood ear mushroom) as a novel ingredient for sweet food applications. Although A. polytricha and Tremella fuciformis (commonly used in Chinese desserts) are biologically distinct species, both share gelatinous textures and are used in rehydrated dried form. Inspired by traditional Chinese dessert preparations using T. fuciformis, this research examined the viscosity and chemical composition of broths prepared from A. polytricha and T. fuciformis to assess their potential as sweet food ingredients.
[Methods] Dried samples (5 g each) of both mushrooms were soaked in 500 mL of purified water for over 8 hours and then heated in a pressure cooker for 1 hour followed by 30 minutes of heating under atmospheric pressure . The viscosity of the resulting broth was measured using a Brookfield viscometer (TVB-15, TOKISANGYO). In addition, A. polytricha broth were prepared at higher concentrations (10 g, 20 g, 30 g) to evaluate concentration-dependent viscosity changes. Protein concentration was quantified using the Bicinchoninic Acid (BCA) assay. To analyze the chemical composition, 2 mL of each broth was freeze-dried, re-dissolved in deuterium oxide (D2O), and subjected to one-dimensional 1D 1H-NMR spectroscopy using an AVANCE III-HD 500 MHz spectrometer.
[Results] The broth of T. fuciformis at 5 g showed higher viscosity compared to the same amount of A. polytricha. However, when A. polytricha was increased to 30 g, its broth exhibited viscosity levels comparable to that of T. fuciformis. Protein quantification revealed low protein content in both samples, with A. polytricha at 167.7ug/mL and T. fuciformis at 214.5ug/mL . These results suggest that the viscosity observed is largely attributed to polysaccharide content rather than proteins. 1D 1H-NMR spectra showed a characteristic signal around 1.2 ppm in the T. fuciformis broth, likely originating from fucose, a sugar also commonly found in seaweeds. This indicates that the presence of fucose or similar sugars may contribute to the higher viscosity observed in T. fuciformis.
