Winged Bean Case Study

The winged bean (Psophocarpus tetragonolobus) is a twining, perennial herbaceous legume which can climb to 3-4 meters (Kantha and Erdman, 1985). As a leguminous plant, winged bean can be used in almost all parts of the plant. Fruit, leaves, flowers, bulbs and seed are edible and contain high protein and oil (Kotaru et al., 1987; Dwiani et al., 2014). The mature, dry seed is the most nutritious part of the winged bean. Their outstanding nutritive quality is based, above all, on their high protein content (30-42 percent) and their favorable amino acid composition (Shultes et al., 1981; Garcia and Palmer, 1983; Kantha and Erdman, 1985; Okezie and Martin, 1986; Prakash et al., 1987; Ibuki et al., 1987; Gross, 1988; Cerny et al., 2006; Dwiani
The content of carbohydrate is a little different with other varieties of winged bean, 33.0% (Ekpenyong and Borchers, 1981), 34.7% (Garcia and Palmer, 1980), 33.3% and 28-31.6% (Schultes et al., 1981). Level carbohydrate of winged bean flour compares in the middle with other seed flour. For some fruit seed flour, the level of carbohydrate range between 15 % in peach and 78% in Suriname cherry (Wani et al., 2007; Lima et al., 2014). Some legume flour has a carbohydrate content higher than winged bean, pea (72% d.b.), lentil (69% d.b.) and chickpea (67% d.b.) (Ettoumi and Chibane,
The principal decomposition process begins with a rapid dehydration and decomposition of hydroxyl groups in glucose rings to form water molecules. During this step the main chain breaking occurs when C-C-H, C-O and C-C bonds break (Liu et al., 2010). The gaseous decomposition products consist mainly of H2O, CO, CO2, compounds as CH4 and C2H4. A prominent peak is recorded between 271oC and 404.2oC in the DTG curves indicating the possibility of a simple mechanism of reaction or the unification of reaction mechanisms multiple (Opfermann, 2000; Gomez et al., 2011). The winged bean flour shows two new steps of decomposition after the stability. A decomposition that was attributed to decomposition and oxidation of organic matter (amylose and amylopectin) that occurs in consecutive reaction and with mass loss of 42.09% and 32.95% respectively. The final residue (ash) was