Judul: Evaluasi Sensori Produk Gule Domba dalam Kemasan Retort Pouch dengan Metode RATA (Rate-All-That-Apply)
Abstrak: Gule domba dalam kemasan retort pouch merupakan produk olahan daging dalam kemasan yang sedang dikembangkan oleh CV XYZ. Proses pengembangan suatu produk memerlukan tahap evaluasi sensori untuk mengetahui respon sensori terhadap produk. Evaluasi sensori dilakukan dengan metode RATA (Rate-All-That-Apply). Penelitian ini bertujuan mendeskripsikan profil atribut sensori produk gule domba dalam kemasan retort pouch dan kaleng berdasarkan persepsi konsumen serta mengidentifikasi perbedaan tingkat kesukaan konsumen secara overall dan atribut sensori produk gule domba dalam kemasan retort pouch dan kaleng. Tahapan penelitian ini yaitu focus group discussion, seleksi panelis, persiapan dan penyajian sampel dengan dua sampel uji, pengujian sensori, dan analisis data menggunakan uji-t sampel independen. Hasil pengujian menunjukkan bahwa gule domba dalam kemasan retort pouch dan kaleng memiliki atribut sensori yaitu rasa manis, asin, gurih, pedas, aroma rempah bumbu gule, aroma prengus domba, warna cokelat jingga, tekstur berserat, tekstur empuk, kenampakan berminyak, bersantan, dan kental. Selain itu, teridentifikasi perbedaan yang signifikan pada tingkat kesukaan konsumen secara overall. Gule domba dalam kemasan retort pouch lebih disukai dibandingkan dengan gule domba dalam kemasan kaleng. Kemudian, teridentifikasi perbedaan yang signifikan pada atribut sensori rasa gurih, pedas, aroma rempah bumbu gule, aroma prengus domba, warna cokelat jingga, tekstur berserat, kenampakan bersantan, dan kekentalan., Lamb curry in retort pouch packaging is packaged meat product that is being developed by CV XYZ. The process of developing a product requires sensory evaluation to determine the sensory response of the product. Sensory evaluation was carried out using RATA (Rate-All-That-Apply) method. This study aims to describe sensory attributes profile of lamb curry product in retort pouch and can packaging based on consumer perceptions and identify differences in overall level of consumer preference and sensory attributes of lamb curry products in retort pouch and can packaging. This research is divided into five stages, are focus group discussion, panelist selection, sample preparation, sensory testing, and data analysis using independent sample t-test. The results show that the lamb curry in retort pouch and can packaging has sensory attributes, namely sweet, salty, savory, spicy, curry spices aroma, prengus aroma, orange brown color, fibrous, tender, oily, coconut milk appearance, and thickness. In addition, a significant difference were identified in the overall level of consumer preference. Lamb curry in retort pouch packaging is preferable to lamb curry in cans. Then, significant differences were identified in sensory attributes of savory, spicy, curry spices aroma, prengus aroma, orange brown color, fibrous, coconut milk appearance, and thickness.
Keyword: atribut sensori, gule domba, RATA (Rate-All-That-Apply), retort pouch

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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