Thickening agents effects on sodium binding and other taste qualities of soup systems

Low sodium chicken broth with NaCl added to provide Na⁺ concentrations in typical reduced Na⁺ soups (144 and 288 mg Na⁺/240 mL serving) was thickened with commonly used gum, starch, or flour food additives. Xanthan gum suppressed saltiness as the result of ionic binding of Na⁺, as determined by sensory evaluation and ²³Na NMR spectroscopy. Saltiness was affected by added NaCl (p = 0.0001), thickener (p < 0.01), and added NaCl thickener (p < 0.01), and positively correlated with chicken and overall flavors (p = 0.0001). Cornstarch provided body, no suppression of salt taste, and the greatest salt enhancement of chicken and overall flavors. In complex food systems, temperature and other factors affected Na⁺ binding as measured by NMR pointing to the need for a new model.