Agustin, IkaRatna (2014) Karakterisasi Konsentrat Protein Kacang Tunggak (Vigna Unguiculata L. Walp) Dari Berbagai Fraksi Protein Berdasarkan Kelarutan. Magister thesis, Universitas Brawijaya.
Abstract
Kacang tunggak (Vigna unguiculata L. Walp) adalah salah satu legume yang paling banyak ditanam di daerah tropis. Disamping harganya yang murah, kacang tunggak juga berpotensi sebagai sumber protein nabati, sehingga dapat mendukung program diversifikasi pangan bergizi tinggi. Penelitian ini bertujuan untuk mengembangkan potensi kacang tunggak sebagai bahan pangan non kedelai, mengkaji pemanfaatan kacang tunggak dalam bentuk konsentrat protein yang dibuat berdasarkan kelarutan protein, yakni fraksi albumin, globulin, glutelin, dan prolamin serta mengkaji dan membandingkan sifat kimia dan fungsional tepung dan konsentrat proteinat kacang tunggak sehingga dapat diaplikasikan pada sistem pangan dengan tepat. Penelitian ini dilakukan dengan menggunakan Rancangan Acak Lengkap terdiri dari 4 level yakni metode presipitasi isoeletrik albumin, presipitasi isoelektrik globulin, presipitasi isoelektrik glutelin, dan presipitasi aseton prolamin. Data yang diperoleh dianalisis menggunakan Analysis of Variance (ANOVA) dan dilanjutkan dengan uji BNT selang kepercayaan 5%. Penelitian ini terdiri dari pembuatan tepung kacang tunggak, penentuan pH kelarutan masing-masing fraksi protein kacang tunggak (albumin, globulin, glutelin), dan ekstraksi fraksi protein kacang tunggak berdasarkan titik isoelektrik masing-masing fraksi protein (albumin, globulin, glutelin), sedangkan untuk fraksi prolamin, pengendapannya dengan presipitasi aseton. Dari hasil penentuan pH kelarutan fraksi protein kacang tunggak yakni fraksi protein albumin, globulin, dan glutelin memiliki pH kelarutan minimum berturut-turut pH 4,0; 4,2; dan 5,0 serta kelarutan maksimum berturut-turut pada pH 10, 12, dan 10. Kadar air tertinggi pada fraksi albumin (17,23%) dan terendah pada globulin (8,31%). Kadar protein tertinggi pada albumin (73,06±1,72%) dan terendah pada prolamin (17,23±1,68%). Hasil uji sifat fungsional tepung dan konsentrat protein kacang tunggak menunjukkan glutelin mempunyai daya serap air tertinggi (2,43±0,15 ml/g); prolamin mempunyai daya serap minyak tertinggi (2,86±0,42 ml/g), indeks aktivitas pengemulsian tertinggi (17,60±3,29 m2/g) dengan indeks stabilitas pengemulsi selama 46,12 menit, dan swelling power terbaik (1,76±0,48 g/g); albumin memiliki kapasitas buih tertinggi (45,33±9,87%). Hasil analisis SDS-PAGE, tepung kacang tunggak diperoleh 3 bands (BM 29,92; 43,24; 55,27 kDa), albumin mempunyai 3 bands (18,01; 34,67; 51,35 kDa), globulin mempunyai 2 bands (39,46 dan 58,45 kDa), glutelin memiliki 3 bands (16,68; 37,60; 56,45 kDa), dan prolamin memiliki 2 bands (45,11 dan 60,25 kDa).
English Abstract
Cowpea (Vigna unguiculata L. Walp) is one of most legume widely grown in tropics. Cowpea also has potential as a source of vegetable protein and it can support high nutritious food diversification program. This study aims to develop potential of cowpea as non-soy food, assess utilization of cowpea in form of protein concentrate by ir solubility, i.e. fraction of albumin, globulin, glutelin, and prolamin as well as reviewing and comparing chemical and functional properties of flour and cowpea protein concentrates that can be applied to food systems. study was conducted using completely randomized design with 4 levels consist of albumin isoeletric precipitation, globulin isoelectric precipitation, glutelin isoelectric precipitation, and prolamin acetone precipitation. Data were analyzed using Analysis of Variance (ANOVA) and continued by LSD test 5 %. study consist of cowpea flour production, determination of solubility pH pf each cowpea protein fractions (albumin, globulin, glutelin), and extraction of cowpea protein fractions by isoelectric point of each protein fraction (albumin, globulin, glutelin), whereas for prolamin fraction, it was performed by acetone precipitation. results of ir solubility of cowpea protein fractions albumin, globulin, and glutelin showed a minimum solubility at pH 4.0; 4.2 and 5.0 as well as maximum solubility at pH 10, 12, and 10. highest water content was found in albumin (17.23%) and lowest was found in globulin (8.31%). highest protein content was found in albumin (73.06±1.72%) and lowest was found in prolamin (17.23±1.68%). In case of functional properties, flour and cowpea protein fractions showed that glutelin had highest water absorption capacity (2.43±0.15 ml/g); prolamin had highest oil absorption capacity (2.86±0.42 ml/g), emulsifying activity index (17.60±3.29 m2/g) with emulsifying stability index for 46.12 min, and swelling power (1.76 ±0.48 g/g); albumin had highest foaming capacity (45.33±9.87%). In SDS-PAGE analysis, cowpea flour showed 3 bands (BM 29.92, 43.24, 55.27 kDa), albumin showed 3 bands (18.01, 34.67, 51.35 kDa), globulin obtained 2 bands (39.46 and 58.45 kDa), glutelin showed 3 bands (16.68, 37.60, 56.45 kDa) and prolamin showed 2 bands (45.11 and 60.25 kDa).
| Item Type: | Thesis (Magister) |
|---|---|
| Identification Number: | TES/641.356.592/AGU/k/041402147 |
| Subjects: | 600 Technology (Applied sciences) > 641 Food and drink > 641.3 Food |
| Divisions: | S2/S3 > Magister Teknologi Hasil Pertanian, Fakultas Teknologi Pertanian |
| Depositing User: | Hasbi |
| Date Deposited: | 15 Apr 2014 11:18 |
| Last Modified: | 22 Apr 2019 02:39 |
| URI: | http://repository.ub.ac.id/id/eprint/159111 |
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