American Journal of Food Science and Technology
ISSN (Print): 2333-4827 ISSN (Online): 2333-4835 Website: Editor-in-chief: Hyo Choi
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American Journal of Food Science and Technology. 2017, 5(6), 238-244
DOI: 10.12691/ajfst-5-6-3
Open AccessArticle

Isolation of Protein from Defatted Lentil Flour

Zar Zar Oo1, , Thwe Linn Ko2 and Soe Soe Than3

1Industrial Chemistry Department, Yadanabon University, Mandalay, Myanmar

2Industrial Chemistry Department, University of Mandalay, Myanmar

3Industrial Chemistry Department, University of Yangon, Yangon, Myanmar

Pub. Date: November 10, 2017

Cite this paper:
Zar Zar Oo, Thwe Linn Ko and Soe Soe Than. Isolation of Protein from Defatted Lentil Flour. American Journal of Food Science and Technology. 2017; 5(6):238-244. doi: 10.12691/ajfst-5-6-3


The main purpose of this research work was to isolate the most refined form of protein from lentil for food processing. In this research work, lentil (Lens culinaris L.) was collected from Monywa Township, Sagaing Region and nutritional characteristics such as moisture content, ash content, fat content, carbohydrate content, protein content and fiber content were determined. The fat of raw bean flour was removed by bulk soaking in ethanol and also by soxhlet extraction using ethanol as solvent before isolating the protein. In addition, the fiber and starch from defatted lentil flour was removed by alkaline extraction and acid precipitation method to isolate the protein (isoelectric precipitation). Protein solubility, water and oil absorption capacity, emulsifying capacity and stability, foaming capacity and stability of lentil protein isolate have been determined. The solubility curve corresponding to the lentil protein isolate indicated the minimum solubility at pH 4 (protein solubility of 20 %) and maximum solubility at pH 12 (protein solubility of 85 %) respectively. The lentil protein isolate had water absorption capacity of 1.82± 0.07 mL H2O/g. protein and oil absorption capacity of 1.95±0.06 mL oil/g. protein. It was found that emulsifying activity and stability of isolated lentil protein were 73.44± 0.03 % and 41± 0.07% while foaming capacity and stability were 22.67± 0.06 % and 50.11± 0.05 %. Isolated lentil protein improved texture appearance and taste than the lentil flour and thus it can better be used as nutrition and functional ingredients in many food products.

defatted lentil flour solvent extraction isoelectric precipitation functional properties lentil protein isolate

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[1]  Kudre,T.G,Benjakul ,S.& Kishimura, H. “Comparative study on chemical compositions and properties of protein isolates from Mung bean, Black bean and Bambara groundnut”, Journal of Sciences and Food Agriculture, 93 (10). 2429-2436.Feburary.2013,
[2]  Butt, M. S. & Batool, R. “Nutritional and functional properties of some promising legumes protein isolates”. Pakistan Journal of Nutrition, 9. (4), 373-379. 2010.
[3]  Habib Ullah, et al. “Proximate and mineral composition of Mung bean, Sarhad Journal of Agriculture”,23 (2).1-4.2007.
[4]  George Amponsah, Zjen Ma & Joyce Irene Boye. “Crop- legume”, Food Processing: Principles and Applications, 305-337. 2014.
[5]  Berrios, J.D.J, “Extrusion cooking of legumes: Dry bean flours”. Encyclopedia of Agricultural, Food and Biological Engineering, 1-8. 2006.
[6]  Sibt-e-Abbas., et al, “Nutritional and functional properties of protein isolates extracted from defatted peanut flour” International Food Research Journal,22 (4).153-1537.2015.
[7]  Tharanathan, R.N. & Mahadevamma, S., “Grain legumes-a boon to human nutrition”. Trends in Food Science and Technology, 14. 507-518, 2003.
[8]  Ladjal Ettoumi,Y.. & Chibane .M. “Some physico-chemical and functional properties of pea, chickpea and lentil whole flours”, International food Research Journal, 22 (3). 987-996 .2015.
[9]  Siddiq M, Ravi R, Harte J.B,Dolan K.D, “Physical and functional characteristics of selected dry bean (Phaseolus vulgaris L.)”, Food Science and Technology. 232-237.2010.
[10]  Wani.I.A,Sogi D.S.Shivhare U.S,Grill B.S., “Physico-chemical and functional properties of native and hydrolyzed kidney bean (Phaseolus vulgaris L.) Protein Isolates”, Food Science and Technology.53 (1). 278-284. 2013.
[11]  Suliman, M. A., et al, “Solubility as influenced by pH and NaCl concentration and functional properties of lentil proteins isolate”. Pakistan Journal of Nutrition.5(6).589-593. 2006.
[12]  Akaerue BI, Onwuka GI, “Evaluation of the yield, protein content and functional properties of Mung bean [Vigna radiate (L.) Wilczek] protein isolates as affected by processing”, Pakistan Journal of Nutrition, 9 (8). 728-735, August, 2010.
[13]  Jayasena V., Chih H.J, Nasar-Abbas S.M, “Efficient isolation of lupin protein”, Food Australia, 63 (7). 306-309. 2011.
[14]  Garba, U, Kaur G, “Protein isolates: Production, functional Properties and applications”, International Research Journal of Chemistry (IRJC), 6 (3). 35-45.January, 2014.
[15]  Shabnum Shaheen,et al. “Comparative nutritional analysis between Vigna radiata and Vigna mungo of Pakistan”, African Journal of Biotechnology,11 (25). 6694-6702. March. 2012.
[16]  Seyam, A.A., Banank, O.J & Breen, M.D, “Protein isolates from navy and pinto Beans: their uses in macaroni products”, Journal of Agricultural Food and Chemistry.31.499-502.1983.
[17]  AOAC, Association of Official Analytical Chemists, Official Method of Analysis.17th ed., Washington, DC. 5-15, 2000
[18]  Aurelia, I., et al, “Chemical and functional characterization of chickpea protein derivates”, Journal of Food Technology, 5. 12-14. 2009.
[19]  Sathe, S .K., Deshpande, S .S. and Salunkhe, D. K., “Functional properties of winged bean( psophocarpus tetragonolobus L.DC) proteins”, Journal of Food Science, 47, 503-509, 1982.
[20]  Lin, M. J .Y., Humbert, E. S and Sosulki, F. W., “Certain funciton al properties of sunflower meal products”. Journal of Food Science.39.368, 1974.
[21]  Volkert, M. A and B. P. Kelin, “Protein dispersibility and emulsion characteristics of flour soy products”. Journal of Food Science, 44, 43-96, 1979.
[22]  Lawhon, J. T., C. M. Gater and K. F .Mattil, “Whippable extract from glandless cottonseed flour”, Journal of Food Science, 37, 317-321, 1972.
[23]  M.Qayyum, M. Butt, “Composition analysis of some selected legumes for protein isolate recovery”, Journal of Animal and Plant Sciences, 22(4). 1156-1162. 2012.
[24]  Josefina Porras-Saavedra, et al, “Comparative study of functional properties of protein isolates obtained from three Lupinus species”, Advanced in Bioresearch, 4 (4). 106-116. December, 2013.