Acid-base buffering properties of five legumes and selected food in vitro

Problem statement: In vitro acid-Buffering Capacity (BC) values of 5% (dry matter) aqueous homogenized suspension of five legumes (broad bean, lentils, chickpea, kidney bean and lupine) and of selected antacid home preparations (cow's milk, almond, peanut, licorice, carob and lettuce stem) were investigated within and among samples from their respective initial pH until pH was decreased to 1.5. BC was the highest for cow's milk, carob, licorice and lettuce stem (BC values 1.65-1.97), intermediate for almond and peanut (BC values, 1.37-1.64) and the lowest for selected legumes (0.84-1.36). Approach: The purpose of this study was to measure in vitro the buffering capacity potential of legumes and other foods commonly used in Jordan as heartburn remedies to determine the ability of these products to de-acidify, neutralize acid, or increase pH levels of an acid and a base solution. Results: BC of the studied legumes showed positive and strong correlations, with protein, aspartic and glutamic amino acids contents (R = 0.95, 0.94, 0.89, respectively) and relatively weak correlation with phosphorus content (R = 0.38). Conclusion/Recommendations: The differences in BC within and among studied samples were largely due to the differences in their chemical compositions. Protein, fiber, ash, organic acids and aspartic and glutamic acids contents and alkalinity of ashes showed significant BC, while high fat content in almond and peanut failed to show considerable BC. © 2010 Science Publications.