98 Jurnal MIPA 39 (2) (2016): 98-106 Jurnal MIPA http://journal.unnes.ac.id/nju/index.php/JM PROFIL PROTEIN SUSU DAN PRODUK OLAHANNYA R. Susanti 1  E Hidayat 2 1 Jurusan Biologi, Fakultas MIPA, Universitas Negeri Semarang, Indonesia 2 SD Negeri 1 Suka Mulya, Kecamatan Lemong, Pesisir Barat, Lampung Info Artikel _______________________ Sejarah Artikel: Diterima Agustus 2016 Disetujui September 2016 Dipublikasikan Oktober 2016 _______________________ Keywords: protein profile; milk; dairy product _____________________________ Abstrak __________________________________________________________________________________________ Penelitian ini bertujuan untuk menganalisis kadar protein dan profil protein pada beberapa susu (susu kedelai, susu kambing) dan olahannya (yogurt, tofu). Kadar protein diukur dengan metode Lowry, sedangkan profil protein dianalisis menggunakan SDS PAGE. Data yang diperoleh dianalisis secara deskriptif. Kadar protein tertinggi pada sampel yang dianalisis terdapat pada produk yogurt A (579,5 mg/ml), disusul susu kedelai (289,99 mg/ml) dan susu kambing (133,1 mg/ml). Analisis profil protein terlihat pita protein dengan mobilitas terendah sampai tertinggi terletak pada berat molekul 14-150 KDa. Pita protein khas yang hanya dimiliki susu kambing adalah pita 150kDa. Sementara pita protein khas yang hanya dimiliki susu kedelai adalah pita 44 kDa dan 55kDa. Pita protein yang khas hanya dimiliki yogurt A (dengan bakteri Lactobacillus bulgaricus dan Streptococcus thermophillus) adalah pita 65Da. Semua jenis susu dan olahannya memiliki pita 70kDa, kecuali susu kedelai. Profil protein susu kedelai dan tofu menunjukkan profil protein yang sangat berbeda, namun keduanya memiliki pita 18kDa. Abstract __________________________________________________________________________________________ This study aimed to observe protein level and profiles on some milks (soy milk, goat's milk) and dairy (yogurt, tofu) product. Protein content was observed by Lowry method, whereas the protein profiles were analyzed by polyacrylamide gel electrophoresis. Data were analyzed descriptively. The highest protein content of the observed sample was in yogurt A products (579,5 mg/ml), followed by soy milk (289,99 mg/ml) and goat's milk (133,1 mg/ml). Analysis of protein profiles showed protein bands with lowest to highest mobility lies in the molecular weight of 14-150 KDa. Typical protein band of goat's milk was a 150kDa band. While the typical protein bands of soy milk were 44 kDa and 55kDa band. The typical protein band of yogurt A (with Lactobacillus bulgaricus and Streptococcus thermophillus bacterium) was 65Da. All types of milks and dairy had 70kDa band, except for soy milk. Protein profile of soy milk and tofu was very different, but both had 18kDa band. © 2016 Universitas Negeri Semarang  Alamat korespondensi: Kampus Sekaran Gunungpati Semarang 50229 ISSN 0215-9945