Pembuatan Isolat dan Penetapan Kadar Protein Kacang Edamame (Glycine max (L.) Merr) dengan Metode Kjeldahl dan Bradford

Abstract

Background: Edamame beans have a fairly high protein content. To obtain pure protein, protein isolation is carried out. One alternative for obtaining protein isolate from edamame beans can be done using the acid-base method. Analysis of protein levels can be done qualitatively and quantitatively. Qualitative analysis can be carried out using the Biuret method, while quantitative analysis can be carried out using the Kjeldahl method and Bradford method. Objective: This study aims to determine the levels of protein isolate in edamame beans (Glycine max (L.) Merr.) obtained using the Kjedahl method and the Bradford method. Method: Edamame beans are extracted using NaOH 0.1 N to pH 10 and then followed by a precipitation process with HCl 2 M to pH 4-4.5. Then centrifugation is carried out at a speed of 3500 rpm for 30 minutes at a temperature of 4oC. The centrifugation precipitate was taken and dried using an oven. Protein levels were determined by the Kjeldahl method and the Bradford method. Results: Edamame bean protein isolate using the acid base method obtained 1.2568 grams in 10 gram samples with a protein yield (%) of 12.56%. The protein content of edamame beans using the Kjeldahl method is 0.14%. Meanwhile, the protein content of edamame beans using the Bradford method was 6.09% ± 0.0102. Conclusion: The protein isolate content of edamame beans using the Bradford method was greater than that of the Kjeldahl method