Nani Ratnaningsih, Suparmo, Eni Harmayani, Yustinus Marsono
Background and Objective: Legumes were studied extensively in the past because of their protein contents but they have now become valuable for their low glycemic index (GI), which is attributed to high amylose and resistant starch contents. This study aimed to evaluate the in vitro starch digestibility and estimated glycemic index (eGI) of native starches from five varieties of cowpea (Vigna unguicuiata) cultivated in Indonesia. Materials and Methods: Five varieties of cowpea (namely KT4, KT5, KT7, KT8 and KTL) were extracted their starches using wet milling method. The in vitro digestibility and eGI of cowpea starches were determined using method of Englyst and Goni. Results: Cowpea starches had low RDS content, from 4.09% (KT7) to 7.51% (KT4) but high SDS, from 19.66% (KT5) to 27.07% (KTL) and RS, from 65.75% (KTL) to 76.15% (KT5). The RAG and SAG contents of the cowpea starches ranged from 3.77% (KT7) to 6.79% (KT8) and from 18.56% (KT5) to 25.13% (KT8), respectively. The eGI of cowpea starches varied from 45.46±0.23 (KT5) to 48.14±0.38 (KT8). Conclusion: Cowpea starches have high SDS and RS contents and low GI, therefore they are suitable as a dietary carbohydrate alternative for the management of obesity, diabetes mellitus, cardiovascular disease and certain cancers. © 2017 Nani Ratnaningsih et al.
Department of Food Processing Education, Faculty of Engineering, Yogyakarta State University, Kampus Karangmalang, Yogyakarta, 55281, Indonesia; Department of Food and Agricultural Product Technology, Faculty of Agricultural Technology, Gadjah Mada University, Jl. Flora No. 1, Bulaksumur, Yogyakarta, 55281, Indonesia
