The effect of pasta cooking method (unsalted versus salted water) on sodium absorption: an <i>in vitro</i> digestion study

Abstract Information on sodium absorption during digestion in various sections of the gastrointestinal tract is limited. Our study aimed to determine whether the cooking method (water with 16 g of salt per 1 L vs. unsalted water) affects sodium bioavailability during in vitro digestion. We analysed five types of pasta that differed in composition. We demonstrated that sodium absorption from cooked pasta in the human gastrointestinal tract ranges from approximately 62% (unsalted water) to nearly 100% (salted water). We also found that the highest sodium absorption occurred in the small intestine, regardless of cooking method or pasta type. Statistically significant higher percent of sodium absorption was confirmed for pasta cooked in salted water compared to that cooked in unsalted water for three of five types of pasta: pasta with seaweed, durum wheat pasta, and whole grain wheat-rye pasta. Cooking in salted water had a significant impact on increasing sodium bioavailability in the gastrointestinal tract, and the degree of sodium absorption from pasta was positively correlated with the sodium content of the product, which in turn depended on the salt concentration in the cooking water. In our study, more than 90% of the Na was absorbed from all types of pasta cooked in salted water.