Judul: Characteristics of Gelatin from Tilapia Fish Scales (Oreochromis niloticus) and Gourami Fish (Osphronemus goramy)
Abstrak: Sisik merupakan salah satu limbah hasil samping perikanan yang dapat digunakan sebagai bahan baku alternatif pembuatan gelatin. Gelatin adalah produk turunan protein yang dihasilkan melalui degradasi kolagen. Perlakuan yang digunakan dalam penelitian ini adalah pengunaan sisik ikan yang berbeda, yaitu sisik ikan nila (Oreochromis niloticus), sisik ikan gurami (Osphronemus goramy), serta sisik campuran ikan nila dan gurami. Analisis statistik yang digunakan adalah analisis ANOVA dan uji lanjut Duncan. Kualitas gelatin terbaik diperoleh dari jenis sisik campuran ikan gurami dan ikan nila. Rendemen yang dihasilkan dari gelatin sisik ikan tersebut yaitu 14,45±0,28%; kadar air 11,04±0,18%; kadar abu 0,49±0,25%; kekuatan gel 208,29±2,6 bloom; viskositas 7,26±0,02 mPas; setting point 18,60±1,90ºC; dan pH 7,11±0,06. Gelatin sisik ikan gurami, sisik ikan nila serta sisik campuran ikan gurami dan ikan nila menunjukkan rantai ß, a1, a2 dan hasil FTIR menunjukkan gugus fungsi khas gelatin yaitu amida A, amida I, amida II dan amida III., Scales are a by-product of fisheries that can be used as an alternative raw material for making gelatin. Gelatin is a protein derivative product produced through collagen degradation. This research aims to determine the influence of different types of fish scale raw materials. The treatments used in this study were the use of different fish scales, namely tilapia fish scales (Oreochromis niloticus), gourami fish scales (Osphronemus goramy) and mixed scales of tilapia fish and gourami fish. The statistical analysis used was ANOVA analysis and Duncan's post-hoc test. The best quality gelatin is obtained from mixed types of gourami and tilapia fish scales. The yield produced from fish scale gelatin was 14.45±0.28%; water content 11.04±0.18%; ash content 0.49±0.25%; gel strength 208.29±2.6 bloom; viscosity 7,26±0,02 mPas; setting point 18.60±1.90ºC; and pH 7.11±0.06. The gelatin of gourami fish scales, tilapia fish scales and mixed scales of gourami fish and tilapia fish shows ß, a1, a2 chains and FTIR results show the typical functional groups of gelatin, namely amide A, amide I, amide II and amide III.
Keyword: gelatin, sisik, halal, nila, gurami, gelatin, scales, halal, tilapia, gourami

Judul: Characterization of Tilapia Fish Scale Gelatin (Oreochromis niloticus) Extraction Process Optimization Results Using Response Surface Methodology
Abstrak: Sisik ikan nila menjadi salah satu sumber bahan baku halal yang dapat dimanfaatkan untuk produksi gelatin ikan. Penelitian ini bertujuan menentukan kondisi pretreatment yang optimum melalui penggunaan konsentrasi NaOH dan HCl yang tepat berdasarkan metode Response Surface Methodology (RSM) serta menentukan karakteristik gelatin hasil optimasi. Variabel bebas yang digunakan, yaitu konsentrasi NaOH dan konsentrasi HCl dengan variabel respon penelitian meliputi, rendemen, kadar air, kadar abu, kekuatan gel, viskositas, pH, dan setting point. Hasil optimasi diperoleh respon optimum pada konsentrasi NaOH 0,05 M dan konsentrasi HCl 0,257 M. Hasil verifikasi keadaan optimum memperoleh gelatin dengan rendemen 17,20±0,36%, kadar air 2,42±0,19%, kadar abu 0,47±0,02%, kekuatan gel 223,448±5,55 Bloom, viskositas 15,37±0,29 mPas, pH 6,87±0,08, dan setting point 19,63±0,06℃. Gelatin hasil optimasi memiliki gugus fungsi amida A, B, I, II, III dan bobot molekul menunjukkan rantai β 241,048 kDa; α_1 161,318 kDa dan α_2 100,646 kDa., Tilapia scales are one of halal raw sources that can be utilized for fish gelatin production. This study aims to determine the optimum pretreatment conditions through the use of the right NaOH and HCl concentrations based on the Response Surface Methodology (RSM) and determine the characteristics of the optimized gelatin. The independent variables were used, such as NaOH concentration and HCl concentration with response variables including yield, moisture content, ash content, gel strength, viscosity, pH and setting point. Based on this study, it showed the optimum response at NaOH concentration of 0,05 M and 0,257 M for HCl concentration. The verification results of the optimum conditions obtained gelatin with a yield of 17,20±0,36%, moisture content of 2,42±0,19%, ash content of 0,47±0,02%, gel strength of 223,448±5,55 Bloom, viscosity of 15,37±0,29 mPas, pH 6,87±0,08, and setting point of 19,63±0,06℃. The optimized gelatin has amide functional groups A, B, I, II, III and the molecular weight shows β chain 241,048 kDa; α_1 161,318 kDa dan α_2 100,646 kDa.
Keyword: gelatin, halal, optimization, RSM, scales

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.
Keyword: