Judul: Utilization of Seaweed Gracilaria sp. in the Artificial Rice Production by Extrusion Method
Abstrak: Beras tiruan merupakan produk olahan berbentuk seperti butiran beras namun terbuat dari bahan pangan yang mengandung pati. Gracilaria sp. merupakan rumput laut penghasil agar yang kaya akan serat dan sudah dibudidayakan di Indonesia. Penelitian dilakukan untuk menentukan formulasi dan karakteristik beras tiruan dengan pemanfaatan rumput laut Gracilaria sp. yang dikomposisikan dengan tepung jagung, tepung singkong dan tepung beras menggunakan metode ekstrusi. Penelitian menggunakan rancangan acak lengkap (RAL) dengan uji lanjut Duncan dan hedonik menggunakan Kruskal Wallis dengan uji lanjut Multiple Comparison. Beras tiruan dengan penambahan tepung rumput laut Gracilaria sp. memberikan pengaruh terhadap komposisi kimia dan kesukaan panelis dengan parameter aroma netral, warna sedikit gelap, dan tekstur kompak. Beras tiruan dengan perlakuan RL10 merupakan formulasi terbaik. Beras tiruan yang dihasilkan memiliki kadar air 11,27%, kadar abu 0,21%, kadar lemak 1,07%, kadar protein 3,55%, kadar karbohidrat 95,17%, kadar fenol 23,135 mg/kg, kadar tanin 0,095%, serat larut air 2,92%, serat tidak larut air 3,64%, dan serat total sebesar 6,56%., Artificial rice is a processed product shaped like rice grains but made from foodstuffs that contain starch. Gracilaria sp. is agarose producer and it is rich in fiber and has been cultivated in Indonesia. Research was conducted to determine the formulation and characteristics of artificial rice with the utilization of seaweed Gracilaria sp. were composed with cornstarch, cassava flour and rice flour using extrusion methods. The study used a complete randomized design (CRD) with duncan and hedonic test using Kruskal Wallis with further test of Multiple comparison. Artificial rice with the addition of seaweed flour Gracilaria sp. influenced the chemical composition and preferences of the panelists with neutral aroma parameters, slightly dark colors, and compact textures. Artificial rice with RL10 treatment is the best formulation. Artificial rice contained moisture 11.27%, ash 0.21%, fat 1,07%, protein 3.55%, carbohydrate 95,17%, phenol 23,135 mg/kg, tannin 0.095%, water-soluble fiber 2,92%, water-insoluble fiber 3,64%, and total fiber 6.56%.
Keyword: artificial rice, composition, seaweed, total fiber

Judul: Characteristics of Artificial Rice with the Addition of Seaweed Gracilaria sp.
Abstrak: Rumput laut Gracilaria sp. mengandung serat pangan dan senyawa polifenol yang dapat dimanfaatkan dalam produk diversifikasi pangan beras tiruan. Beras tiruan adalah produk olahan sumber karbohidrat non padi yang memiliki kandungan karbohidrat mendekati beras yang terbuat dari tepung lokal atau tepung beras. Beras tiruan dengan penambahan rumput laut memiliki potensi sebagai bahan pangan pengganti beras untuk sumber karbohidrat yang tinggi serat. Penelitian ini bertujuan menentukan formulasi dan karakteristik beras tiruan dengan penambahan rumput laut Gracilaria sp. dengan metode ekstrusi serta menentukan formulasi terbaik beras tiruan. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan faktor konsentrasi rumput laut Gracilaria sp. 0%, 5%, 10% dan 15%. Beras tiruan formula terpilih berdasarkan metode Bayes adalah beras tiruan dengan penambahan rumput laut Gracilaria sp. 10%. Kriteria penilaian penting beras tiruan meliputi parameter sensori dan komposisi kimia. Beras tiruan yang dihasilkan memiliki nilai sensori yang disukai panelis dengan nilai kadar air 7,29% sesuai batas yang ditentukan SNI 6128:2008, senyawa total fenol 253,94 mg/kg, komponen tanin 0,27% serta kandungan serat pangan sebesar 13,85% yang termasuk beras tiruan dengan tinggi serat sehingga telah mencukupi asupan serat pangan harian., Gracilaria sp. contains dietary fiber and polyphenolic compounds that can be used in artificial rice diversification products. Artificial rice is a non-rice carbohydrate source processed product that has a carbohydrate content close to that of rice made from local flour or rice flour. Artificial rice with the addition of seaweed has the potential as a food substitute for rice for a high-fiber carbohydrate source. This study aims to determine the formulation and characteristics of artificial rice with the addition of seaweed Gracilaria sp. with the extrusion method and determined the best formulation of artificial rice. This study used a Completely Randomized Design (CRD) with the concentration factor of seaweed Gracilaria sp. 0%, 5%, 10%, and 15%. Artificial rice selected formula based on Bayes method was artificial rice with the addition of seaweed Gracilaria sp. 10%. Important assessment criteria for artificial rice include sensory parameters and chemical composition. The artificial rice produced had a sensory value that preferred by the panelists, the water content of 7,29% according to the limits set by SNI 6128:2008, total phenol compound 253,94 mg/kg, 0,27% tannin component, and has a food fiber content of artificial rice of 13,85 % food fiber content which includes artificial rice with high fiber so that it has enough daily dietary fiber intake.
Keyword: artificial rice, dietary fiber, Gracilaria sp., polyphenol

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model