Antioxidant abilities of a substance can be estimated using different methods. The ferric iron reducing ability is one of the most commonly used methods to evaluate the antioxidant activity of a solution given that most known antioxidants act as electron donors to stabilize oxidative species. The ferric iron reducing capacity of extracts and suspensions of soybean seeds culinary forms are summarized in Fig. 4. Except for USE which exhibited a reducing activity greater than that of the control at concentrations 12.5 and 25 μg/ml, HSE and all the culinary forms exhibited a ferric iron reducing ability lower than that of BHT at all the concentrations.USE showed a significant difference in the reducing capacity compared to all the culinary forms of soybean seeds except for HUS. Hulling did not affect the ferric iron reducing ability of soybean seeds. Sprouting did not maintain the ferric iron reducing capacity while roasting was observed to better preserve it. The high ability of URS to reduce the ferric iron could be the consequence of its phenoliccontent since a high correlation have been demonstrated between phenolic contents and antioxidant abilities of soybean seeds and many other fruits, leaves, roots or seeds was demonstrated