Judul: Effect of Processing Methods on Physical Characteristics, Nutritional Content, and Protein Quality of Pigeon Peas (Cajanus cajan)
Abstrak: Kacang gude berpotensi sebagai pangan sumber protein nabati. Penelitian ini bertujuan menganalisis pengaruh metode pengolahan terhadap karakteristik fisik, kandungan gizi, dan mutu protein kacang gude. Rancangan percobaan yang digunakan adalah rancangan acak lengkap dengan tiga perlakuan yaitu G1 (rendam), G2 (rendam-rebus), G3 (rendam-kukus) dan satu sampel kontrol (G0) pada dua kali ulangan. Analisis yang dilakukan diantaranya karakteristik fisik, analisis kandungan gizi, analisis daya cerna protein, analisis komposisi asam amino, skor asam amino, dan analisis Protein Digestibility Correct Amino Acid Score (PDCAAS). Metode pengolahan rendam, rendam-rebus, dan rendam-kukus berpengaruh nyata terhadap karakteristik fisik, kandungan gizi, dan mutu protein kacang gude (p<0,05). Daya cerna protein tertinggi diperoleh kacang gude yang diolah rendam-kukus (G3) yaitu sebesar 92,12%. Kacang gude yang diolah rendam-kukus mengandung histidin sebesar 0,59%, isoleusi sebesar 0,78%, leusin sebesar 1,07%, valin sebesar 1,56%, metionin sebesar 0,56%, sistein sebesar 0,45%, fenilalanin sebesar 0,74%, dan tirosin sebesar 0,55%. Kacang gude yang diolah rendam-kukus memiliki skor asam amino 54,69% dan PDCAAS 50,39%. Mutu protein % kacang gude yang diolah rendam-kukus tergolong berkualitas cukup baik., Pigeon peas have the potential to be a food source of vegetable protein. This research aims to analyze the effect of processing methods on the physical characteristics, nutritional content, and protein quality of pigeon peas. The experimental design used was a completely randomized design with three treatments, namely G1 (soak), G2 (soak-boil), G3 (soak-steam) and one control sample (G0) in two replications. The analyzes carried out include physical characteristics, nutritional content analysis, protein digestibility analysis, amino acid composition analysis, amino acid score analysis, and Protein Digestibility Correct Amino Acid Score (PDCAAS) analysis. The processing methods of soaking, soaking-boiling, and soaking-steaming had a significant effect on the physical characteristics, nutritional content, and protein quality of pigeon peas (p<0.05). The highest protein digestibility was obtained from pigeon peas that had been soaked and steamed (G3), namely 92.12%. Pigeon peas that have been soaked and steamed contain 0.59% histidine, 0.78% isoleucine, 1.07% leucine, 1.56% valine, 0.56% methionine, 0.45% cysteine, 0.74% phenylalanine, and 0.55% tyrosine. Pigeon peas that have been soaked-steamed have an amino acid score of 54.69% and PDCAAS 50.39%. The protein quality of pigeon peas that have been soaked and steamed is quite good quality.
Keyword: AAS, PDCAAS, pigeonpea, protein digestibility, proximate analysis

Judul: The Impact of Enzyme Addition on the Physical, Chemical, and Biological Value of Peeled Jack Bean Meal (Canavalia Ensiformis L.)
Abstrak: Penelitian ini bertujuan menginvestigasi pengaruh pengolahan dan penambahan enzim protease dan enzim polisakarida non pati (NSP) terhadap karakteristik fisik, komposisi kimia, energi dan protein metabolis kacang koro tanpa kulit. Penelitian ini menggunakan rancangan acak lengkap dengan 4 perlakuan dan 4 ulangan. Sebanyak 20 ekor ayam digunakan dalam penelitian ini, terdiri dari 16 ekor untuk mengukur energi dan protein metabolis dan 4 ekor untuk mengukur energi endogen. Perlakuan terdiri dari P0 (kacang koro tanpa kulit), P1 (P0 + enzim protease), P2 (P0 + enzim NSP), dan P3 (P0 + enzim protease + enzim NSP). Hasil analisis menunjukkan penambahan enzim protease dan NSP pada kacang koro berpengaruh nyata (P<0,05) terhadap karakteristik fisik, komposisi kimia, dan energi metabolis. Hal ini dikarenakan enzim protease dapat memecah protein menjadi peptida sehingga lebih mudah untuk diserap oleh hewan dan enzim NSP dapat memecah polisakarida non-pati sehingga dapat meningkatkan densitas pakan. Simpulannya, penambahan enzim protease dan NSP pada kacang koro tanpa kulit dapat meningkatkan energi metabolis, menjadikannya sebagai bahan pakan sumber protein alternatif yang menjanjikan untuk ayam broiler., The objective of this research was to investigate the effects of processing, including the addition of protease enzymes and non-starch polysaccharide (NSP) on the physical characteristics, chemical composition, metabolizable energy and protein of peeled jack bean meal. The study employed a completely randomized design with 4 treatments and 4 replications. A total of 20 animals were used in this study, including 16 for measuring metabolizable energy and protein and 4 broiler chickens to measure endogenous. The treatments consisted of P0 (peeled jack bean meal), P1 (P0 + protease enzymes), P2 (P0+ NSP enzymes), and P3 (P0+ protease enzyme + NSP enzyme). The results of the analysis showed that the addition of protease and NSP enzymes to the peeled jack bean meal had a significant (P<0.05) effect on chemical composition, physical characteristics, and metabolizable energy. This was because protease enzyme specifically broke down proteins into smaller peptides, making them more accessible for absorption by the animals and NSP enzymes broke down non-starch polysaccharides which increased the bulk density of the feed. In conclusion, the addition of protease and NSP enzymes to the peeled jack bean meal increase metabolizable energy and making it a promising alternative protein source for broiler chickens
Keyword: metabolic energy, NSP enzyme, Peeled jack bean meal, physical characteristics, protease enzyme, protein digestibility

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.
Keyword: