Judul: Characteristics and Scale Magnification of Pangasius Fish Skin Gelatin Extraction and Its Application in The Manufacture of Marshmallow
Abstrak: Gelatin banyak dimanfaatkan pada berbagai bidang. Gelatin umumnya bersumber dari hewan mamalia seperti babi dan sapi yang menimbulkan kekhawatiran terhadap aspek keagamaan. Kulit ikan patin diharapkan dapat menjadi sumber alternatif bahan baku gelatin. Kualitas gelatin salah satunya dipengaruhi oleh proses pretreatment. Proses pretreatment dapat dilakukan dengan basa, asam, atau kombinasi basa dan asam. Kombinasi pretreatment dengan larutan basa dan asam dapat meningkatkan sifat-sifat gelatin. Penelitian ini bertujuan menganalisis pengaruh konsentrasi dan waktu perendaman NaOH terhadap karakteristik gelatin yang dihasilkan, menentukan perlakuan terpilih yang akan dilakukan perbesaran skala ekstraksi, menganalisis karakteristik gelatin dari perbesaran skala ekstraksi, dan menguji aplikasinya pada pembuatan marshmallow. Rancangan dalam penelitian ini menggunakan Rancangan Acak Lengkap Faktorial dengan 2 faktor yaitu konsentrasi NaOH (0,1 M: 0,2 M: dan 0,3 M) dan waktu perendaman NaOH (1 jam dan 3 jam). Analisis data menggunakan one-way analysis of variance (ANOVA) dengan uji lanjut Duncan dan menggunakan independent sample t-test dengan taraf kepercayaan 95%. Karakteristik gelatin yang dianalisis meliputi rendemen, kadar air, kadar abu, pH, kekuatan gel, dan viskositas. Karakteristik marshmallow yang dianalisis meliputi kadar air, kadar abu, dan uji sensori rating hedonik dan Rate-All-That-Apply (RATA). Hasil karakteristik gelatin dengan perlakuan perbedaan konsentrasi NaOH dan lama perendaman NaOH memiliki interaksi yang berbeda nyata terhadap parameter rendemen, pH, kekuatan gel, dan viskositas, sedangkan pada parameter kadar air dan kadar abu gelatin tidak terdapat perbedaan yang nyata. Gelatin dengan konsentrasi NaOH 0,3 M dan waktu perendaman 1 jam menjadi perlakuan terpilih untuk dilakukan pembesaran skala ekstraksi dengan nilai rendemen sebesar 23,83%, kadar air sebesar 10,16%, kadar abu sebesar 0,44%, pH sebesar 6,44, kekuatan gel sebesar 229,38 bloom, dan viskositas sebesar 72,00 mps. Hasil gelatin kulit ikan patin pada semua perlakuan memiliki karakteristik yang memenuhi standar gelatin menurut SNI 8622-2018 dan GMIA 2019. Gelatin dapat diaplikasikan pada pembuatan marshmallow. Hasil uji sensori rating hedonik antara marshmallow hasil penelitian memiliki hasil yang tidak berbeda nyata dengan marshmallow komersial, hal tersebut menunjukan bahwa marshmallow hasil penelitian dapat diterima dan disukai oleh panelis.
Keyword: gelatin, marshmallow, NaOH, pangasius, skin

Judul: Effect of Multistage Extraction on the Gelatin Properties of Pangasius Fish Skin (Pangasius hypopthalmus)
Abstrak: Gelatin merupakan produk hidrolisis kolagen yang dapat membentuk gel reversibel. Salah satu bahan baku gelatin adalah kulit ikan patin. Ekstraksi tunggal gelatin menyisakan kolagen di dalam struktur kulit ikan patin sehingga perlu dilakukan ekstraksi bertingkat. Ekstraksi bertingkat bertujuan meningkatkan rendemen sekaligus mempertahankan kualitas gelatin. Produksi gelatin diawali dengan pretreatment di dalam NaOH 0,2 M dan asam asetat 0,05 M. Ekstraksi bertingkat menggunakan kombinasi suhu 55-75, 55-80, dan 65-75 oC selama 10 jam pada setiap tahap dengan pelarut akuades. Rancangan percobaan yang digunakan yaitu Rancangan Acak Lengkap (RAL) dan uji lanjut Duncan. Penggunaan metode ekstraksi bertingkat meningkatkan rendemen dibanding ekstraksi tunggal. Perbedaan perlakuan berpengaruh terhadap viskositas, kekuatan gel, dan distribusi bobot molekul gelatin. Perlakuan tidak berpengaruh terhadap pH, kadar air, kadar abu, serta setting point. Hasil terbaik diperoleh pada perlakuan ekstraksi 65-75oC yang menghasilkan rendemen (25.05±0.35%), viskositas (63.67±2.08 mps), serta kekuatan gel (255.69±2.94 bloom). Perbedaan perlakuan menyebabkan perbedaan tingkat kerusakan pada struktur stratum compactum kulit ikan patin., Gelatin is hydrolyzed collagen that can form a reversible gel. One source of gelatin is Pangasius skin. Gelatin single extraction left some collagen in Pangasius skin so that a multistage extraction is needed. Multistage extraction aims to increase yield and maintain gelatin quality. Gelatin production began with pretreatment in 0,2 M NaOH and 0,05 M acetic acid. This extraction used some combination of 55-75, 55-80, and 65-75 oC for 10 hours at each stage in distilled water. The experimental designs in this study were completely randomized design (CRD) and Duncan's advanced test. Multistage extraction improved gelatin yield from a single extraction. Different treatments affected viscosity, gel strength, and molecular weight distribution. Treatments did not affect pH values, water contents, ash levels, and setting points. The best results were obtained at 65-75 oC treatment which resulted in a yield (25.05±0.35%), viscosity (63.67±2.08 mps), and gel strength (255.69±2.94 bloom). Different treatments caused different damage to the stratum compactum of Pangasius skin.
Keyword: gel, histologi, kolagen, reversibel, suhu

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: