Natural biopolymer masks the bitterness of potassium chloride to achieve a highly efficient salt reduction for future foods.

Abstract

Potassium chloride (KCl) can be considered as the most ideal salt replacer to reduce dietary sodium intake and ease various health risks of a high-sodium diet. However, a high proportion of sodium chloride (NaCl) replacement with KCl remains a challenge, because KCl has an inherent metallic bitterness. This study demonstrates a strategy for this bitterness-masking using a natural polysaccharide kappa-carrageenan to specifically bind with K⁺ and reduce the amount of free K⁺ as bitter stimulant. The results show that carrageenan can significantly slow down the release and diffusion of K⁺, leading to a reduced bitter taste of KCl in the mouth. Up to 50% replacement of NaCl by KCl can be achieved. Furthermore, the use of carrageenan-KCl-NaCl complex as salt substitutes can regulate mineral absorption (Na, K, Ca) and reduce hypertension and renal injury risks in the animal tests. In conclusion, this natural biopolymer-based strategy successfully masks the bitter of salt-replacer KCl, opening a route to the universally applicable salt-reduction in future foods.