微波辅助提取银耳多糖工艺优化及其流变、凝胶特性

优化微波辅助提取银耳多糖工艺，并研究银耳多糖的流变特性及凝胶特性。利用单因素试验和正交试验确定最佳提取条件为液料比50∶1（mL/g）、粒度120 目、微波功率400 W、微波时间2.0 h，此条件下银耳多糖的提取率达到（33.25±0.14）%。傅里叶变换红外光谱和流变性质测定结果表明，银耳多糖是一种独特的酸性杂多糖，多糖溶液表现出假塑性流体的性质，随着角频率的增加，动态模量增加，银耳多糖溶液在高频区域可形成弱凝胶结构。通过质构测定表明银耳多糖质量浓度显著影响银耳多糖凝胶的硬度及弹性。流变学测试和质构分析表明，银耳多糖具有良好的流变特性和凝胶特性，可替代部分胶体在食品中的使用。

Optimization of Microwave-Assisted Extraction and Rheological and Gelling Properties of Polysaccharide from Tremella fuciformis

The microwave-assisted extraction of polysaccharides from Tremella fuciformis (TPS) was optimized. The rheological and gelling properties of TPS were studied. Using a combination of single factor and orthogonal array design methods, the optimum extraction conditions were determined as follows: solvent-to-solid ratio 50:1 (mL/g), particle size 120 mesh, microwave power 400 W, and radiation time 2.0 h, which resulted in a yield of polysaccharide of (33.25 ± 0.14)%. Fourier-transform infrared (FTIR) spectroscopy and rheological measurement showed that TPS was a distinctive acidic heteropolysaccharide, and the TPS solution behaved as a pseudoplastic fluid. The dynamic modulus was increased with increasing frequency and the TPS solutions could form a weak gel structure in the high-frequency region. Texture profile analysis (TPA) showed that TPS concentration significantly influenced its gel hardness and springiness. Rheology TPA suggested that TPS had good rheological and gelling properties for application as a partial substitute for colloids in food.