Judul: Ekstraksi Gelatin Halal dari Limbah Tulang Ikan Patin (Pangasius hypophthalmus) dengan Ultrasound Assisted Extraction
Abstrak: Hingga saat ini sumber gelatin terbesar berasal dari kulit babi yang menyumbang 46% dari total gelatin. Hal ini menjadi penghambat bagi pengembangan produk pangan di negara dengan mayoritas muslim seperti Indonesia. Salah satu sumber yang prospektif untuk dikembangkan adalah tulang ikan yang menyumbang 10-20% dari bobot ikan, dengan budi daya ikan terbanyak, yaitu ikan patin. Penelitian ini bertujuan mengekstraksi gelatin dari limbah tulang ikan patin dengan bantuan ultrasonik menggunakan variasi waktu ekstraksi 3, 5, dan 7 jam. Berdasarkan hasil yang diperoleh waktu ekstraksi 5 jam menjadi perlakukan terbaik yang memberikan rendemen tertinggi, yaitu 5 ± 1.03% dengan nilai kekuatan gel, viskositas, dan pH berturut-turut 147.74 ± 0.83 g Bloom, 14.63 ± 0.31 cP, dan 6.76 ± 03. Analisis gugus fungsi dengan fourier transform infrared (FTIR) telah memberikan serapan khas dari gelatin dengan munculnya puncak amida. Hasil analisis berat molekul dengan sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) diperoleh berat molekul gelatin dengan rentang 120.08-155.82 KDa.
Keyword: gelatin, patin, tulang ikan, ultrasonik, waktu ekstraksi

Judul: Kualitas Gelatin dari Kulit Ikan Patin (Pangasius hypohthalmus) Hasil Iradiasi Gamma
Abstrak: Gelatin adalah protein yang dihasilkan dari hidrolisis kolagen tulang dan kulit. Hewan yang menjadi sumber gelatin utama yakni babi dan sapi. Sumber alternatif yang berpotensi untuk memperoleh gelatin halal adalah tulang dan kulit ikan. Penelitian ini bertujuan menentukan pengaruh dosis iradiasi sinar gamma 8 dan 16 kGy terhadap karakteristik fisik-kimia gelatin dan jumlah mikrobiologi pada bahan baku kulit ikan patin. Kulit ikan patin diiradiasi sinar gamma dosis 0, 8, dan 16 kGy dengan 3 kali pengulangan. Gelatin dari bahan baku yang diiradiasisinar gamma dosis 8 dan 16 kGy berpengaruh terhadap viskositas gelatin, dosis iradiasi hingga 16 kGy mengakibatkan viskositas larutan gelatin meningkat. Perlakuan iradiasi sinar gamma 8 dan 16 kGy mampu mematikan mikroba pada bahan baku. Karakteristik gelatin yang dihasilkan sudah memenuhi Standar Nasional Indonesia untuk produk gelatin, tetapi kandungan mikrobanya tidakmemenuhi syarat (>10³ CFU/g) karena terjadi rekontaminasi.
Keyword: catfish, gelatin, irradiation

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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