Electronic Theses and Dissertation

Indonesia sebagai negara agraris memiliki keanekaragaman hayati yang tinggi, salah satunya umbi janeng (dioscorea hispida dennst.) yang dikenal masyarakat aceh sebagai boh janeng. umbi ini berpotensi besar sebagai sumber pangan alternatif karena kandungan karbohidratnya yang relatif tinggi sehingga memungkinkan pengolahannya menjadi beragam produk turunan, mulai dari keripik, kerupuk, hingga tepung siap pakai. namun pemanfaatannya masih sangat terbatas karena umbi janeng mengandung senyawa beracun seperti dioskorin, diosgenin, dan asam sianida (hcn) yang berbahaya jika dikonsumsi tanpa pengolahan yang tepat. secara tradisional proses detoksifikasi dilakukan dengan merendam irisan umbi di sungai selama 4 hingga 5 hari, yang dinilai tidak efisien dan tidak ramah lingkungan. penelitian ini dilaksanakan pada bulan oktober 2025 hingga januari 2026, dengan proses pembuatan alat di laboratorium perbengkelan departemen teknik pertanian universitas syiah kuala dan pengambilan data di desa riting, kecamatan indrapuri. perancangan mesin menggunakan pendekatan fungsional dan struktural, yang mana setiap komponen ditentukan bahan, fungsi, dan dimensinya secara sistematis. komponen utama mesin meliputi motor listrik, gearbox, sistem transmisi pulley dan sabuk v, rangka besi siku, tabung, penampung saringan, poros, bantalan, mata pengaduk, serta pipa pembuang. analisis teknik dilakukan dengan menghitung kebutuhan daya, torsi, kecepatan sudut, perencanaan poros, serta tegangan geser. selain itu, dilakukan pengukuran bulk density umbi janeng yang diranjang sebagai dasar perencanaan muatan tabung. tahapan penelitian selanjutnya dengan uji fungsional guna memverifikasi bahwa setiap komponen mesin berfungsi sebagaimana yang telah direncanakan dalam desain awal. hasil penelitian menunjukkan bahwa mesin pembuang racun janeng berhasil dirancang dan dibangun dengan kinerja yang optimal. berdasarkan analisis teknik, mesin membutuhkan daya sebesar 168,35 watt dengan torsi 83,34 nm dan kecepatan pengadukan 19,27 rpm, yang seluruhnya terpenuhi oleh motor listrik berkapasitas 370 watt. diameter poros hasil perhitungan sebesar 37,76 mm dinilai aman karena memiliki momen inersia polar sebesar 10.306,03 mm⁴ dan mengalami tegangan geser sebesar 72,78 n/mm² atau 72,78 mpa akibat torsi sebesar 83,34 n·m. secara fungsional, mesin mampu menurunkan kandungan hcn pada umbi janeng dari 60 ppm menjadi 41,5 ppm, dalam waktu 3 jam pengoperasian jauh lebih efisien dibandingkan metode tradisional yang membutuhkan waktu 24 jam. proses kerja mesin diawali dengan perendaman janeng dalam larutan garam 12 jam, dilanjutkan pengadukan di dalam tabung berisi air menggunakan mata pengaduk berputar, dengan pergantian air secara berulang hingga air tampak jernih. hasil ini membuktikan bahwa mesin pembuang racun janeng layak dikembangkan lebih lanjut sebagai solusi teknologi tepat guna yang efisien, higienis, dan mendukung ketahanan pangan berbasis sumber daya lokal.

Indonesia, as an agrarian country, possesses high biodiversity, one example of which is janeng tuber (Dioscorea hispida Dennst.), locally known in Aceh as boh janeng. This tuber has considerable potential as an alternative food source due to its relatively high carbohydrate content, allowing it to be processed into various derivative products, including chips, crackers, and ready-to-use flour. However, its utilization remains very limited because janeng tuber contains toxic compounds such as dioscorine, diosgenin, and hydrogen cyanide (HCN), which can be harmful if consumed without proper processing. Traditionally, the detoxification process is carried out by soaking sliced tubers in river water for 4 to 5 days, a method considered inefficient and environmentally unfriendly. This research was conducted from October 2025 to January 2026. The machine fabrication process was carried out at the workshop laboratory of the Department of Agricultural Engineering, Universitas Syiah Kuala, while data collection was conducted in Riting Village, Indrapuri District. The machine was designed using functional and structural approaches, in which the material, function, and dimensions of each component were systematically determined. The main components of the machine consisted of an electric motor, gearbox, pulley and V-belt transmission system, angle-iron frame, tank, filter container, shaft, bearings, agitator blades, and discharge pipes. Technical analysis was conducted by calculating the power requirement, torque, angular velocity, shaft design, and shear stress. In addition, the bulk density of sliced janeng tubers was measured as a basis for determining the tank loading capacity. The subsequent research stage involved functional testing to verify that each machine component operated according to the initial design specifications. The results showed that the janeng detoxification machine was successfully designed and constructed with optimal performance. Based on the technical analysis, the machine required 168.35 watts of power, a torque of 83.34 N·m, and an agitation speed of 19.27 rpm, all of which were adequately supplied by a 370-watt electric motor. The calculated shaft diameter was 37.76 mm and was considered safe, with a polar moment of inertia of 10,306.03 mm⁴ and a shear stress of 72.78 N/mm² or 72.78 MPa resulting from a torque of 83.34 N·m. Functionally, the machine was able to reduce the HCN content in janeng tubers from 60 ppm to 41.5 ppm within 3 hours of operation, making it considerably more efficient than the traditional method, which requires 24 hours. The machine operation began with soaking the janeng tubers in a salt solution for 12 hours, followed by agitation in a water-filled tank using rotating agitator blades, with repeated water replacement until the water appeared clear. These results demonstrate that the janeng detoxification machine has potential for further development as an appropriate technology solution that is efficient, hygienic, and supportive of food security based on local resources.