Judul: Sifat Fisikokimia, Organoleptik dan Aktivitas Antioksidan Dendeng Daging Ayam dengan Penambahan Serbuk Bunga Rosella
Abstrak: Dendeng berpotensi mengalami reaksi oksidasi yang dapat dihambat dengan antioksidan. Senyawa antioksidan banyak terkandung dalam bahan alami, seperti bunga rosella. Penelitian ini bertujuan untuk menguji sifat fisikokimia, organoleptik dan aktivitas antioksidan dendeng daging ayam dengan penambahan serbuk bunga rosella. Variabel yang diukur dalam penelitian ini meliputi nilai pH, aw, kadar air, aktivitas penghambatan terhadap 2,2-difenil-1-pikrilhidrazil (DPPH), kapasitas antioksidan, nilai TBARS, dan sifat organoleptik (warna, aroma, tekstur, dan rasa) dendeng daging ayam. Rancangan yang digunakan dalam penelitian ini adalah rancangan acak lengkap (RAL) dengan tingkat penambahan serbuk bunga rosella yang berbeda (0%; 0,15%; 0,30%). Hasil penelitian menunjukkan bahwa penambahan serbuk bunga rosella berpengaruh nyata (p<0,05) terhadap nilai pH yang semakin menurun, serta nilai aw dan kadar air yang semakin meningkat. Penambahan serbuk bunga rosella tidak berpengaruh nyata terhadap nilai TBARS, aktivitas penghambatan DPPH dan kapasitas antioksidan. Secara keseluruhan dendeng daging ayam dengan penambahan serbuk bunga rosella pada taraf 0,15% dan 0,30% tidak memberikan pengaruh terhadap sifat fisikokimia, organoleptik, dan aktivitas antioksidan., Jerky has the potential to undergo oxidation reactions that can be inhibited by antioxidants. Many antioxidant compounds are contained in natural ingredients, such as rosella flowers. This study aimed to examine the physicochemical, organoleptic, and antioxidant activity of chicken meat jerky with the addition of roselle flower powder. The variables measured in this study included pH value, aw, moisture content, inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH), antioxidant capacity, TBARS value, and organoleptic properties (color, aroma, texture, and taste) of chicken meat. The jerky design used in this study was a completely randomized design (CRD) with different levels of rosella flower powder addition (0%; 0.15%; 0.30%). The results showed that the addition of rosella flower powder had a significant effect (p<0.05) on the decreasing pH value and increasing water content. The addition of rosella flower powder did not significantly affect the TBARS value, DPPH inhibitory activity and antioxidant capacity. Overall chicken jerky with the addition of rosella flower powder at the level of 0.15% and 0.30% did not affect the physicochemical, organoleptic, and antioxidant activity properties.
Keyword: antioxsidant, meat chicken jerky, physicochemical sensory, rosella flowers, sensory properties

Judul: Antioxidant Activity and Organoleptic  Properties of Chicken Nuggets Added with Saffron Flower Mash (Crocus Sativus  L)
Abstrak: Safron memiliki banyak kegunaan bagi kesehatan karena memiliki kandungan antioksidan yang tinggi. Penambahan safron pada nugget ayam ditujukan untuk meningkatkan kandungan antioksidannya. Penelitian ini bertujuan menganalisis karakteristik yang meliputi sifat fisikokimia, aktivitas antioksidan dan organoleptik nugget ayam yang diberi penambahan safron sebagai tambahan bumbu pada proses pembuatannya. Penelitian ini menggunakan rancangan acak lengkap (RAL) satu faktor perlakuan dengan tiga kali ulangan pembuatan nugget ayam. Faktor perlakuan tersebut adalah penambahan tepung bunga safron dengan persentase 0%, 0,25%, 0,5%. Hasil penelitian menunjukkan bahwa nugget ayam dengan penambahan tepung bunga safron hingga 0,5% menghasilkan kadar air yang nyata lebih rendah (p<0,05), tanpa perbedaan nilai pH dan aw yang nyata. Penambahan tepung bunga safron pada nugget ayam hingga 0,5% mampu meningkatkan aktivitas antioksidan secara nyata (p<0,05) dan menurunkan kandungan malonaldehida sampai pada batas tidak terdeteksi. Penambahan tepung bunga safron pada nugget ayam baik 0,25% maupun 0,5% pada seluruh kriteria mutu uji hedonik tidak menunjukkan perbedaan yang nyata (p<0,05) dengan nugget ayam tanpa penambahan tepung bunga safron kecuali pada kriteria mutu rasa. Hasil uji mutu hedonik menunjukkan bahwa penambahan tepung bunga safron berpengaruh nyata (p<0,05) terhadap warna, aroma nugget, aroma safron dan rasa. Penambahan tepung bunga safron hingga 0,5% menghasilkan karakteristik nugget ayam yang lebih baik, kecuali pada kriteria mutu rasa yang kurang disukai panelis., Saffron has many health benefits due to its high antioxidant content. The addition of saffron to chicken nuggets is intended to increase its antioxidant content. Thisstudy aimsto analyze the characteristics that include physicochemical properties, antioxidant activity and organoleptic chicken nuggets that were given the addition of saffron as an additional seasoning in the manufacturing process. This study used a completely randomized design (CRD) with one treatment factor with three replications of making chicken nuggets. The treatment factor was the addition of saffron flower flour with a percentage of 0%, 0.25%, 0.5%. The results showed that chicken nuggets with the addition of saffron flower flour up to 0.5% resulted in a significantly lower water content (p < 0.05), without a significant difference in pH and aw values. The addition of saffron flower flour to chicken nuggets up to 0.5% was able to significantly increase the antioxidant activity (p < 0.05) and reduce the malonaldehyde content to an undetectable limit. The addition of saffron flower flour to chicken nuggets both 0.25% and 0.5% on all hedonic test kriteria mutus did not show a significant difference (p < 0.05) with chicken nuggets without the addition of saffron flower flour except for the taste kriteria mutu. The results of the hedonic quality test showed that the addition of saffron flower flour had a significant effect (p < 0.05) on the color, aroma of nuggets, saffron aroma and taste. The addition of saffron flower flour up to 0.5% resulted in better characteristics of chicken nuggets, except for the taste criteria that the panelists did not like.
Keyword: antioksidan, fisikokimia, nugget ayam, organoleptik, tepung bunga safron

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: