Judul: Karakteristik fisikokimia dan sifat fungsional tepung koro benguk (Mucuna pruriens L.)
Abstrak: Indonesia memiliki beragam jenis kacang-kacangan lokal yang potensial dengan kandungan gizi hampir sama dengan kedelai. Namun, potensi tersebut sampai saat ini belum dikembangkan secara optimal. Salah satu komoditas lokal tersebut yaitu koro benguk (Mucuna pruriens L.). Kacang ini memiliki potensi yang cukup besar untuk dikembangkan, salah satunya dibuat menjadi tepung sebagai bahan baku ataupun bahan substitusi sebagian pada berbagai produk pangan olahan. Koro benguk segar mengandung sianida, suatu senyawa yang bersifat toksik. Selain senyawa cun, koro benguk dilaporkan mempunyai manfaat bagi kesehatan karena mengandung senyawa fenolik yang tinggi yang berperan sebagai antioksidan. Perlakuan pendahuluan untuk menurunkan kandungan sianida pada koro benguk perlu dilakukan untuk menjamin keamanan produk. Namun, beberapa perlakuan pendahuluan tersebut Berpeluang merusak zat gizi dan komponen fungsional yang terkandung di dalamnya. Oleh karena itu, penelitian ini bertujuan mengetahui pengaruh perlakuan pendahuluan terhadap karakteristik sikokimia tepung koro benguk. Di samping itu juga menentukan perlakuan pendahuluan yang baik dalam rangka memproduksi tepung koro benguk dengan karakteristik fisikokimia dan sifat fongsional yang diinginkan serta memenuhi aspek keamanan. Penelitian ini terdiri atas dua tahap, yaitu tahap perlakuan pendahuluan dan tahap analisis Asikokimia dan sifat fungsional. Tahap perlakuan pendahuluan dilakukan sebelum penepungan. Adapun perlakuan yang ditentukan antara lain mentah utuh, tanpa kulit, tanpa kulit dan dilanjutkan Serebusan 30 menit, tanpa kulit dan dilanjutkan pengukusan 30 menit, tanpa kulit dan dilanjutkan perendaman (6, 12, dan 24 jam), dan germinasi. Sementara itu, parameter yang dianalisis antara lain proksimat, asam sianida (HCN), total fenol, kapasitas antioksidan, daya cerna protein, dan daya cerna pati. Pada tepung perlakuan terbaik akan dilakukan analisis serat pangan, kalsium, fosfor, dan sifat fisik serta fungsional. Hasil analisis proksimat menunjukkan bahwa perlakuan memberikan pengaruh yang variatif, khususnya terhadap protein dan karbohidrat. Kadar protein tepung koro benguk putih lebih tinggi dibandingkan dengan varietas belang, namun untuk kadar karbohidrat sebaliknya. Perubahan kadar salah satu komponen akibat perlakuan akan berdampak pada kadar komponen lainnya…dst
Keyword: Mucuna pruriens L, Cyanide, Phenolic, Antioxidant, Digestibility

Judul: Karakteristik Fisikokimia dan Sifat Fungsional Tepung Koro Benguk (Mucuna pruriens L.) Berprotein Tinggi
Abstrak: One of food sources that can be potentially developed as high protein food product is mucuna bean. However, nowadays it is still under-utilized. This research aimed to determine the most appropriate process to produce ‘mucuna bean flour’ as material source of high protein flour, to find new method to increased protein content in mucuna flour using enzyme, and to studies its physicochemicals and functional properties. This research was divided into two stages: (1) preliminary research and (2) main research. At the preliminary research, the treatment design to decrease cyanide, (the natural toxin in mucuna seed) was determined using complete randomized experimental design with eight kinds of treatment to two mucuna bean varieties (white and motted). Whereas the main research was the production of high protein flour by enzymatic method with α-amylase enzyme and optimized its production process by the optimal-working-enzyme-factors-base method. After the selection of the best process, the next step was the physicochemical properties and functional quality analysis. At the preliminary research, the white mucuna bean, after going through dehulling treatment continued with 24-hour soaked water treatment, was chosen as the main research sample because it contains cyanide less than 10 ppm (CODEX standard for cyanide) and it contains the highest protein as much as 32%. Results of the main research shows that five factors (initial substrate concentration, enzyme activity, temperature, pH, and time) influenced the optimization process. Enzyme method was successfully lowered nonprotein components. So that, by calculation, protein increased by 28% from 32% to 41%. Mucuna high protein flour bulk density was 0.43 g/ml, the color was brownish white, while the water activity was 0.62. Mucuna high protein flour WAC and OAC were 1.67 ml/g and 1.83 ml/g respectively. The emulsion capacity and stability were 32% and 56%. Foam capacity and stability were 64% and 67%. The best concentration for gelling is 15% and the in vitro protein digestibility is 79%. Mucuna high protein flour has potential to be developed as ingredient for food products especially sausage, bakery and meat analog.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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