Judul: The Presence of Bacteria in Fresh Salted Eggs
Abstrak: Telur asin merupakan telur yang berasal dari bebek dan diawetkan dengan cara diasinkan. Telur dapat mengalami kerusakan dan pembusukan karena adanya kontaminasi bakteri. Penelitian ini bertujuan untuk mengisolasi dan mengidentikasi keberadaan bakteri yang dapat menurunkan kualitas telur asin segar dengan menghitung jumlah total mikroba serta isolasi dan identifikasi bakteri. Sampel yang diambil berupa 10 sampel telur bebek segar yang lolos candling, 10 sampel telur asin segar black yolk dari nomor kandang yang sama dan dilakukan pooling, serta adonan pasta pada jam ke-0, jam ke-3, dan jam ke-6 dengan pengulangan sebanyak tiga kali. Pengujian dilakukan di Laboratorium Mikrobiologi Medik, Sekolah Kedokteran Hewan dan Biomedis, Institut Pertanian Bogor. Identifikasi bakteri dilakukan secara fenotipik berdasarkan sifat Gram dan uji biokimia. Hasil penelitian menunjukkan bahwa jumlah bakteri total pada telur bebek segar lolos candling berada di bawah rentang maksimum menurut SNI Nomor 7388:2009, yaitu 1x105 cfu/g, sedangkan sampel adonan pasta dan telur asin segar black yolk berada di atas standar jumlah cemaran mikroba maksimum. Bakteri yang teridentifikasi berasal dari 6 genus, yaitu Escherichia spp., Enterobacter spp., Proteus spp., Staphylococcus spp., Pseudomonas spp., dan Bacillus spp., Salted eggs are eggs that are preserved by salting. Eggs can be damaged and spoilage due to bacterial contamination. This study aims to isolate and identify the presence of bacteria that can affect the quality of fresh salted eggs by counting the total number of microbs also isolation and identification of bacteria. The samples taken include 10 fresh duck eggs that passed the candling, 10 fresh black yolk salted eggs from the same cage number and pooled, and also pasta dough at 0, 3, and 6 hours with three repetitions. The testing was conducted at the Microbiology Medic Laboratory, School of Veterinary Medicine and Biomedicine, IPB Univeristy. Bacterial identification was done phenotypically based on Gram staining and biochemical tests.The results of the research showed that the total number of bacteria in fresh salted eggs passed through candling was below the maximum range from SNI Number 7388:2009 which is 1x105 cfu/g, while samples of pasta dough and black yolk fresh salted eggs were above the limit for the maximum number of bacterial contaminations. The bacteria identified were came from 6 genus, which is Escherichia spp., Enterobacter spp., Proteus spp., Staphylococcus spp., Pseudomonas spp., and Bacillus spp.
Keyword: bakteri, black egg yolk, telur asin segar, total jumlah mikroba, bacteria, fresh salted egg, total number of bacteria

Judul: The Presence of Fungi in Fresh Salted Eggs
Abstrak: Telur asin merupakan olahan makanan berbahan dasar telur bebek yang diawetkan dengan proses pengasinan. Adanya kontaminasi cendawan dapat menyebabkan kerusakan dan penurunan kualitas pada telur asin segar. Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi keberadaan cendawan yang mempengaruhi kualitas telur asin dengan metode menghitung total jumlah cendawan, isolasi dan identifikasi = cendawan. Sampel untuk pengujian terdiri dari 10 sampel telur bebek segar yang lolos candling, 10 sampel telur asin segar black yolk, serta adonan pasta pada jam ke-0, jam ke-3, dan jam ke-6 yang dipooling dengan pengulangan sebanyak 3 kali. Pengujian dilakukan di Laboratorium Mikrobiologi Medik, Sekolah Kedokteran Hewan dan Biomedis, Institut Pertanian Bogor. Identifikasi cendawan dilakukan dengan mengamati pertumbuhan morfologi secara makroskopik dan koloni cendawan diperiksa secara mikroskopis. Hasil dari penelitian menunjukkan bahwa jumlah cendawan pada ketiga sampel berada di bawah batas jumlah cemaran sebesar 1x105 koloni/g sesuai dengan SNI Nomor 7388 Tahun 2009. Cendawan yang teridentifikasi yaitu dari genus Aspergillus spp., Penicillium spp., Mucor spp., Candida spp., dan Fusarium spp., Salted duck eggs are a processed food product made from duck eggs preserved through salting. Fungal contamination can lead to deterioration and a decline in quality. This research aimed to isolate and identify the presence of fungi affecting the quality of salted duck eggs through methods including total fungal count, isolation, and fungal identification. Samples for testing comprised 10 fresh duck eggs that passed candling, 10 fresh salted eggs with black yolks, and dough paste at 0, 3, and 6 hours, pooled with three repetitions. Testing was conducted at the Microbiology Medic Laboratory, School of Veterinary Medicine and Biomedical Sciences, IPB University. Fungal identification involved macroscopic morphological observations and microscopic examination of fungal colonies. The study results indicated that fungal counts in all samples were below the contamination limit of 1x105 colonies/g as per SNI Number 7388 Year 2009. Identified fungi included genera Aspergillus spp., Penicillium spp., Mucor spp., Candida spp., and Fusarium spp
Keyword: Identifikasi, cendawan, Black egg yolk, telur asin segar, Fungi, Fresh Salted Eggs, Identification

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: