Judul: Effect of Acid Soaking Time on Characteristics of Pangasius Fish Skin Gelatin and Its Utilization for Hard Capsules
Abstrak: Kulit ikan patin merupakan bahan baku alternatif yang lebih ekonomis, aman, dan halal untuk pembuatan gelatin. Penelitian ini bertujuan menentukan pengaruh waktu perendaman dalam asam terhadap karakteristik gelatin serta menentukan karakteristik kapsul keras yang dihasilkan. Waktu yang digunakan pada proses perendaman asam yaitu 2, 3, dan 4 jam. Hasil analisis karakteristik gelatin menggunakan ANOVA menunjukkan bahwa perlakuan waktu perendaman asam tidak berpengaruh nyata terhadap karakteristik gelatin. Perlakuan yang diberikan menghasilkan rendemen 19,04-21,49%; kekuatan gel 190,013-234,6 bloom; viskositas 6,94-7,45 cP; derajat keasaman (pH) 5,94-6,205; kadar air 5,3727,824%; kadar abu 0,303-0,836%; setting point 18,67-22,33 ℃, serta tidak terdeteksi adanya logam berat. Karakteristik gelatin yang dihasilkan telah sesuai dengan standar GMIA 2019 dan SNI 8622-2018. Karakteristik kapsul yang dibuat dari bahan baku gelatin kulit ikan telah memenuhi standar kapsul menurut Kementerian Kesehatan Republik Indonesia., Pangasius fish skin is an alternative raw material that is more economical, safe and halal for the manufacture of gelatin. This study aims to determine the effect acid soaking time on the characteristics of the gelatin and to determine the characteristics of the resulting hard capsules. The time used in the soaking acid process is 2, 3, and 4 hours. The analysis result of the gelatin characteristics using ANOVA showed that the acid soaking time did not significantly affect the characteristics of gelatin. The treatment given resulted yields 19.04-21.49%; gel strength 190.013-234.6 bloom; viscosity 6.94-7.45 cP; degree of acidity (pH) 5.946.205; water content 5.372-7.824%; ash content 0.303-0.836%; setting point 18.6722.33 ℃, and no heavy metals were detected. The characteristics of the resulting gelatin comply with GMIA 2019 and SNI 8622-2018 standards. The characteristics of capsules made from fish skin gelatin have met capsule standards according to the Ministry of Health of the Republic of Indonesia.
Keyword: acetic acid, capsule, gelatin, pangasius

Judul: Effect of Citrict Acid Soaking Volume and Time on Catfish Skin for Optimazion of Gelatin Extraction
Abstrak: Gelatin berasal dari protein kolagen yang diperoleh melalui hidrolisis kolagen kulit dan tulang hewan yang dapat dimanfaatkan sebagai bahan baku pembuatan kapsul keras. Penelitian dilakukan untuk mendapatkan formula proses pembuatan gelatin optimal dari kulit ikan patin dengan Response Surface Methodology (RSM) serta dilakukan analisis fisik dan kimia kapsul keras gelatin. Rancangan eksperimen yang digunakan yaitu Central Composite Design (CCD) yang terdiri dari dua variabel yaitu volume asam sitrat (300 mL, 400 mL dan 500 mL) dan waktu perendaman asam sitrat (6 jam, 12 jam dan 18 jam) pada suhu ekstraksi 65°C selama 8 jam dengan delapan respon yaitu rendemen, kadar air, kadar abu, pH, kekuatan gel, viskositas, setting point dan melting point. Ekstraksi gelatin optimal pada perlakuan volume 500 mL dan waktu perendaman 18 jam menghasilkan gelatin dengan kualitas yang telah sesuai standar GMIA 2019 dan SNI 86222018. Nilai validasi keadaan optimal yang diperoleh yaitu rendemen 22,41±0,20% kadar air 6,72±0,40%; kadar abu 0,30±0,05%; pH 5,26±0,02; kekuatan gel 266,08±14,68 bloom; viskositas 59±0,16 mps; setting point 20,33±1,5°C; dan melting point 24,67±1,52°C. Karakteristik kapsul keras yang dihasilkan telah sesuai dengan standar Depkes RI 1995., Gelatin is derived from collagen protein obtained through hydrolysis of animal skin and bone collagen which can be used as raw material for making hard capsules. The research was conducted to obtain the optimal formula for the process of making gelatin from catfish skin with Response Surface Methodology (RSM) and physical and chemical analysis of hard gelatin capsules were carried out. The experimental design was the Central Composite Design (CCD) which consisted of two variables, namely the volume of citric acid (300 mL, 400 mL and 500 mL) and the immersion time of citric acid (6 hours, 12 hours and 18 hours) at an extraction temperature of 65°C for 8 hours with eight responses, namely yield, water content, ash content, pH, gel strength, viscosity, setting point and melting point. Optimal gelatin extraction at treatment volume of 500 mL and soaking time of 18 hours produced gelatin with quality that complies with GMIA 2019 and SNI 8622-2018 standards. The optimal validation value obtained was yield of 22,41±0,20% water content 6,72±0,40%; ash content 0,30±0,05%; pH 5,26±0,02; gel strength 266,08±14,68 bloom; viscosity 59±0,16 mps; setting point 20,33±1,5°C; and a melting point of 24,67±1,52°C. The characteristics of the hard capsules produced are in accordance with the 1995 Ministry of Health standards.
Keyword: Catfish, Gelatin, Hard capsule, Optimal, Response Surface Methodology

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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