Judul: Perbaikan nilai tambah limbah tulang ikan tuna, Thunnus sp. menjadi gelatin serta analisis fisika-kimia
Abstrak: Ikan tuna pada umumnya dimanfaatkan untuk produksi pengalengan dan pembekuan, baik utuh maupun dalam bentuk loin beku. Produk ikan tuna beku sebagian besar hanya memanfaatkan daging ikannya saja, sedangkan sisa-sisa pemanfaatan lain berupa kepala, sirip dan tulang belum dimanfaatkan secara optimal. Saat ini kepala, sirip dan tulang hanya dibuat tepung ikan dengan nilai ekonomi yang masih rendah. Tulang ikan tuna dapat dijadikan gelatin, karena di dalam tulang ikan tuna mengandung protein kolagen. Gelatin merupakan polipeptida yang diperoleh melalui beberapa tahapan degradatif dari protein kolagen. Proses pembuatan tulang ikan tuna menjadi gelatin digunakan HCl dengan konsentrasi 4, 5 dan 6% dan suhu ekstraksi 80, 85 dan 90 oC. Tujuan dari penelitian ini adalah mempelajari pembuatan gelatin dari tulang ikan tuna dengan menggunakan metode asam serta menganalisis sifat fisika kimia gelatin yang dihasilkan.
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Judul: Ekstraksi dan Sifat-Sifat Gelatin Kulit Ikan Tuna Sirip Kuning (Thunnus albacares)
Abstrak: Gelatin merupakan produk yang banyak diperlukan dalam berbagai industri, yaitu industri pangan maupun non-pangan. Penggunaan gelatin yang sangat luas menyebabkan kebutuhan gelatin Indonesia selalu mengalami peningkatan dari tahun ke tahun. Hingga saat ini, belum terdapat industri gelatin dalam negeri, sehingga perlu penelitian tentang sumber gelatin, terutama dari limbah perikanan. Tujuan penelitian ini yaitu melakukan ekstraksi gelatin kulit ikan tuna sirip kuning dengan perlakuan suhu (55, 65 dan 75 ˚C). Sifat-sifat gelatin yang diteliti yaitu rendemen, pH, kekuatan gel, viskositas, analisis FTIR, SDS-PAGE dan komposisi asam amino. Suhu ekstraksi 75 ˚C terpilih sebagai hasil terbaik. Perlakuan tersebut menghasilkan rendemen yang dihasilkan sebesar 17%; pH 5,3; dan kekuatan gel 1789,55 gf; viskositas 104,2 Cp. Terdapat gugus fungsi amida A, I, II, dan III. SDS-PAGE menunjukkan pita β, α1 dan α2. Komposisi asam amino utama yaitu glisin dan prolin.
Keyword: ekstraksi, gelatin, histologi, suhu, tuna sirip kuning

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite