Seaweed (Macrocystis pyrifera) as a sustainable low-sodium natural salt substitute: Conventional solid-liquid extraction v/s ultrasonic extraction

Excess dietary sodium is a key contributor to hypertension and cardiovascular disease. Seaweeds, naturally rich in potassium and other minerals, offer a sustainable source of salt substitutes. In this study, mineral salts were extracted from the brown macroalga Macrocystis pyrifera using (i) solid–liquid extraction in an agitating water bath and (ii) ultrasound-assisted extraction in an ultrasonic bath. The effects of extraction time (5–60 min) and temperature (20–60°C) on salt yield, specific energy consumption (SEC), and mineral composition were evaluated using a full factorial design. Both methods produced salts with high potassium (183 g/kg) and a low sodium-to-potassium (Na/K) ratio (0.46). Conventional solid-liquid extraction delivered higher yields (p