Judul: Cemaran Enterobacteriaceae dalam Daging Ayam yang Dijual di Kota Dili, Timor Leste
Abstrak: Negara Timor-Leste melakukan importasi daging ayam beku dari beberapa negara serta hasil peternakannya sendiri, untuk memenuhi kebutuhan protein hewani masyarakatnya. Kontaminasi mikrob dalam daging ayam yang dijual di Timor Leste dapat terjadi di tingkat penjualan, sehingga tujuan penelitian ini yaitu mengetahui cemaran Enterobacteriaceae pada daging ayam yang dijual di pasar Kota Dili, Timor-Leste. Sebanyak 150 sampel daging ayam segar dan beku diambil dari pasar tradisional dan modern di Timor-Leste. Pengujian jumlah Enterobacteriaceae dilakukan menggunakan metode hitungan cawan dengan media Violet Red Bile Glucose agar. Hasil penelitian ini menunjukkan jumlah Enterobacteriaceae pada sampel daging ayam yang dijual di Timor-Leste adalah 28.613,1±99.322,8 CFU/g dengan jumlah cemaran Enterobacteriaceae paling tinggi sebesar 103.658,3±199.900,4 CFU/g pada sampel daging ayam broiler Timor Leste dan paling rendah sebesar 1.216,7±2.975,2 CFU/g pada daging ayam lokal Timor Leste. Rata-rata jumlah cemaran Enterobacteriaceae pada sampel daging ayam segar yang berasal dari Timor Leste sebesar 52.437±101.437,8 CFU/g, sedangkan pada sampel daging ayam beku yang diimpor Malaysia, Amerika dan Brazil sebesar 16.562,233±34.391,067 CFU/g. Tingginya jumlah Enterobacteriaceae dalam daging ayam yang dijual di pasar menunjukkan tingkat higiene dan sanitasi yang buruk pada saat penanganan dan penjualan ayam di Timor Leste., Timor-Leste imports frozen chicken meat from multiple countries and from their own farm to fulfill the population’s need for animal protein. Microbial contamination of chicken meat may occur during the trading stage, hence, the aim of this study was to determine the microbiological quality of chicken meat based on the number of Enterobacteriaceae contamination in chicken meat from Kota Dili, Timor-Leste. A total of 150 fresh and frozen chicken meat samples were taken from traditional and modern markets in Dili, Timor-Leste. The total plate count method with a Violet Red Bile Glucose agar media was used to determine the Enterobacteriaceae number. The results obtained shows that the number of Enterobacteriaceae on the chicken meat sample sold in Timor-Leste is 28.613,1±99.322,8 CFU/g, with the highest being 103.658,3±199.900,4 CFU/g and the lowest 1.216,7±2.975,2 CFU/g for Timor Leste broiler and native chicken meatrespectively. The average number of Enterobacteriaceae contamination in fresh chicken meat samples was 52,437±101,437.8 CFU/g and in frozen chicken meat samples was 16,562.233±34,391.067 CFU/g.The high total average of Enterobacteriaceae indicates high contamination in chicken meat, which is associated with poor hygiene and sanitation during the handling and trading of chicken meat in Timor-Leste.
Keyword: chicken meat, Enterobacteriaceae, sanitation, Timor-Leste

Judul: Microbial Contamination Level in Chicken Meat from Timor-Leste Based on Total Plate Count
Abstrak: Daging ayam merupakan salah satu produk pangan asal hewan yang paling banyak dikonsumsi di Timor-Leste. Salah satu aspek kualitas daging ayam yang harus diperhatikan adalah kualitas mikrobiologisnya. Penelitian ini bertujuan untuk mengetahui kualitas mikrobiologis dari daging ayam berdasarkan angka lempeng total (ALT) pada daging ayam asal Timor-Leste. Sebanyak 150 sampel daging ayam diambil dari pasar tradisional dan modern di Timor-Leste. Metode ALT dilakukan berdasarkan International Commission on Microbiological Spesification for Foods (ICMSF) tentang Pemeriksaan Mikrobiologi Pangan jumlah total mikroorganisme maksimum adalah 106 CFU/g. Rata-rata Angka Lempeng Total (ALT) pada daging ayam adalah 3,05 × 105 ± 5,66 × 105 CFU/g dengan maksimum 3,96 × 105 CFU/g dan minimum adalah 2,13 × 105 CFU/g. Jika dibandingkan dengan kriteria mikrobiologis yang ditetapkan oleh International Commission on Microbiological Spesification for Foods (ICMSF), 88,7% (83/150) sampel berada di bawah standar ICMSF. Tingginya ALT pada daging ayam mengindikasikan perlunya perbaikan praktik higiene dan sanitasi di pasar., Chicken meat is one of the most widely consumed food products of animal origin in Timor-Leste. One aspect of chicken meat quality that must be considered is the microbiological quality. This study aimed to determine the microbiological quality of chicken meat based on the total plate count (TPC) in chicken meat that sold in Timor-Leste. A total of 150 samples of chicken meat were taken from traditional and modern markets in Timor-Leste. The method of TPC was carried out based on The Compendium of Methods for the Microbiological Examination of Food. According to the International Commission on Microbiological Specification for Foods (ICMSF) on Microbiological Criteria in Food, the maximum number of TPC for food is 106 CFU/g. The result showed that the average TPC in chicken meat were 3,05 × 105 ± 5,66 × 105 CFU/g with the maximum was 3,96 × 105 CFU/g and the minimum were 2,13 × 105 CFU/g. When compared to microbiological criteria established by ICMSF, 88,7% (83/150) samples were below the ICMSF standard. The high number of TPC in chicken meat indicated the need of improvement on hygiene and sanitation practices in the market.
Keyword: Chicken meat, Timor-Leste, Total plate count

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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