中华包革耳粗多糖溶液的流变学特性影响因素

The effects of temperature, pH, salt ions, and sugar solutions on the rheological properties of crude polysaccharide water extract (Naematelia sinensis polysaccharides-water extract, NAP-WE) from Naematelia sinensis were systematically investigated. Through static and dynamic rheological tests, changes in apparent viscosity, storage modulus (G′), and loss modulus (G″) of NAP-WE solutions under different conditions were analyzed. The results showed that NAP-WE exhibited shear-thinning behavior, and variations in temperature, salt ions, pH, and sugar solutions altered its apparent viscosity and gel characteristics. Within the 4-60 ℃ range, the apparent viscosity of 6.0% NAP-WE solution slightly decreased with rising temperature, and its weak-gel properties weakened in high-frequency regions, though it remained non-fluid. Acidic/alkaline environments reduced apparent viscosity and gel strength, but the consistency coefficient (k) and flow behavior index (n) showed minimal changes, confirming its stability within pH 3-9. Na+, K+, and Ca2+ all reduced viscosity and gel strength, with efficacy ranking Na+>Ca2+>K+; excessive Na+ over-shielded charges, altering polysaccharide chain aggregation and loosening the network structure. Glucose/sucrose solutions (4%-8%) decreased apparent viscosity, with sucrose exhibiting stronger effects. Low sugar concentrations (≤4%) minimally impacted gel properties, preserving weak-gel characteristics. In summary, NAP-WE’s rheological behavior is significantly regulated by environmental factors, and its weak-gel properties remain most stable under low temperature, neutral pH, low ion concentration, and low sugar content. The results provide a theoretical basis for applications of NAP-WE in food and pharmaceuticals.