Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2001
Publication Date: 12/2/2001
Citation: MASSEY, L.K., PALMER, R.G., HORNER, H.T. OXALATE CONTENT OF SOYBEAN SEEDS (GLYCINE MAXI LEGUMINOSAE), SOYFOODS AND OTHER EDIBLE LEGUMES. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 2001. v. 49. p. 4262-4266. Interpretive Summary: Soybean is a highly nutritious food source because of its excellent oil and protein content. The Federal Drug Administration has approved a label health claim that foods that contain at least 6.25 g of soy protein per serving reduce the risk of cardiovascular disease. Seeds are rich in isoflavones, compounds that seem to have the potential of reducing bone loss and breast cancer. Soybean seed and soyfoods are high in the chemica oxalate and in calcium. Calcium and oxalate may be combined to produce calcium oxalate. The absorbed calcium oxalate may increase the risk of calcium oxalate kidney stones. Kidney stones are very painful, but also cause an estimated 1.83 billion dollars in direct medical costs (1995 data) in the U.S. Our objective was to assay selected soybean cultivars and commercial soyfoods to determine their calcium and oxalate contents. The amounts of total oxalate in soybean seed and soyfoods exceeds current recommendation for oxalate consumption by individuals who have a history o calcium oxalate stones. This study serves as the basis to find soybean cultivars lower in oxalate, which will have lower risk for kidney stone formation after human consumption.
Technical Abstract: Consumption of soybeans and food products made from them is increasing because of their desirable nutritional value. However, oxalate content of seeds from 11 cultivars of soybean showed relatively high levels of total oxalate from 0.67 g to 3.5 g/100 g dry weight. Oxalate primarily was found as calcium oxalate crystals. Thirteen tested commercial soyfoods contained dbetween 16 to 638 mg total oxalate per serving. These values compare to three other legume foods, peanut butter, refried beans, and lentils, which contained 197, 193, and 100 mg total oxalate per serving, respectively The amounts of total oxalate in soybean seeds, soyfoods, and other common legume foods exceed current recommendations for oxalate consumption by individuals who have a history of calcium oxalate stones. This study serves as the basis to find soybean cultivars lower in oxalate, which will have lower risk for kidney stone formation after human consumption.