Judul: Design of Retort Pouch Packaging and Shelf Life Estimation for Commercial Sterilized Goat Tongseng Product by MSMEs
Abstrak: Produk olahan peternakan penting bagi masyarakat sebagai sumber protein kedua setelah hasil perikanan. Daging kambing sering diolah menjadi sate, sop, soto, gulai, tongseng, dan lainnya. Namun, produk daging kambing siap saji dalam kemasan masih langka karena mayoritas diproduksi saat dipesan. UMKM Produk Steril Komersial seperti HnR Food mengembangkan produk Ready to Eat (RTE) sesuai permintaan konsumen. Sterilisasi dan kemasan yang tepat penting untuk kualitas dan umur simpan produk RTE. Produk RTE memiliki umur simpan lebih lama dengan pengemasan yang sesuai. Pengujian umur simpan dilakukan dengan metode ASLT model Arrhenius. Kemasan retort pouch bag telah sesuai dengan desain proses sterilisasi yang telah ditentukan dan dapat digunakan sebagai kemasan alternatif untuk menggantikan kemasan kaleng dengan harga yang lebih terjangkau. Umur simpan dari produk tongseng kambing yang dikemas dengan kemasan retort pouch bag berhasil untuk diketahui dengan nilai umur simpan yang didapatkan 93 hari atau sekitar 3 bulan pada suhu 25°C dan dapat mencapai 170 hari atau kurang lebih 6 bulan apabila disimpan pada suhu 4°C., Processed livestock products are important to the community as the second source of animal protein after fishery products. Goat meat is commonly prepared as satay, soup, stew, tongseng, and others. However, ready-to-eat goat meat products in packaging are still rare because they are mostly produced upon order. MSME commercial sterilized products like HnR Food developed Ready to Eat (RTE) products according to consumer demand. Proper sterilization and packaging are crucial for RTE product quality and shelf life. RTE products have a longer shelf life with appropriate packaging. Shelf life testing was conducted using the ASLT Arrhenius model. The retort pouch bag packaging was suitable for the specified sterilization process and offered a more affordable alternative to cans. The shelf life of tongseng goat product in the retort pouch bag was determined to be 93 days or approximately 3 months at 25°C and could extend up to 170 days or approximately 6 months when stored at 4°C.
Keyword: Arrhenius, commercial sterilized products, goat tongseng, retort packaging, shelf life

Judul: Determination of Heat Adequacy in Sterilization of Lamb Curry in Retort Pouch Packaging Using Pressure Cooker at CV XYZ
Abstrak: Penggunaan kemasan kaleng sebagai kemasan pangan sterilisasi komersial gulai domba yang disterilisasi menggunakan panci presto dengan sumber panas kompor gas di CV XYZ kurang efisien secara waktu dan biaya karena harganya yang mahal dan kemampuan penetrasi panas yang kurang baik. Retort pouch dapat menjadi kemasan alternatif yang menghemat biaya dan waktu karena kemampuan pindah panasnya lebih besar dibandingkan kaleng dan harganya lebih murah. Penelitian ini bertujuan mengembangkan retort pouch sebagai kemasan produk gulai domba dengan menentukan waktu pemanasan yang dibutuhkan agar produk mencapai kondisi steril komersial. Penelitian dibagi menjadi tiga tahapan, yaitu uji distribusi panas, uji penetrasi panas, dan perhitungan biaya variabel untuk penggunaan kedua jenis kemasan. Hasil uji distribusi panas menunjukkan bahwa penyusunan vertikal merupakan penyusunan yang paling optimal. Berdasarkan hasil uji penetrasi panas, waktu holding selama 60 menit saat sterilisasi gulai domba kemasan retort pouch dapat memenuhi standar pangan steril komersial. Namun dengan memperlama waktu tunda pembukaan katup uap menjadi 30 menit, maka waktu holding dapat dikurangi menjadi 49 menit. Selain itu, kemasan retort pouch juga tidak akan pecah pada semua percobaan waktu tunda. Jika membandingkan penggunaan kedua kemasan dari waktu sterilisasi dan biaya, penggunaan kemasan retort pouch dapat menghemat biaya produksi dibandingkan kemasan kaleng, namun membutuhkan waktu sterilisasi yang lebih lama., The use of cans as commercial sterilization food packaging for lamb curry, which is sterilized using a pressure cooker with gas stove heat source at CV XYZ is less efficient in time and cost because of the high price and poor heat penetration ability. Retort pouches can be an alternative packaging that saves costs and time because their heat transfer capacity is greater than cans and they have cheaper price than cans. This study aims to develop a retort pouch as packaging for lamb curry products by determining the heating time required for the product to reach a commercially sterile condition. This research is divided into three stages, namely heat distribution test, heat penetration test, and calculation of variable costs for the use of both types of packaging. The results of the heat distribution test show that the vertical arrangement is the most optimal. Based on the results of the heat penetration test, the holding time of 60 minutes when sterilizing the lamb curry in retort pouch packaging can meet commercial sterile food standards. However, by extending the delay time for opening the steam valve to 30 minutes, the holding time can be reduced to 49 minutes. In addition, the retort pouch packaging will also not break in all the time delay trials. When comparing the use of the two packages in terms of sterilization time and cost, the use of retort pouch packaging can save production costs compared to canned packaging but requires a longer sterilization time.
Keyword: Heat adequacy test, Pressure cooker, Retort pouch

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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