Judul: Hibiscus sabdariffa Linn
Abstrak: Es krim adalah makanan beku semi padat hasil olahan susu yang dibuat dengan melewati berbagai proses, yaitu pasteurisasi, homogenisasi, pematangan es krim, pengadukan untuk membentuk rongga udara pada adonan es krim, serta pembekuan dalam lemari es. Bunga rosella memiliki kandungan antioksidan yang tinggi. Kandungan antosianin pada bunga rosella mencapai 96 mg dan vitamin C mencapai 280 mg setiap 100 g. Antosianin pada bunga rosella mampu memberikan efek perlindungan terhadap penyakit kardiovaskuler, termasuk penyakit hipertensi. Penelitian ini bertujuan untuk menganalisis sifat fisikokimia, organoleptik dan aktivitas antioksidan es krim yang diberi penambahan bubuk bunga rosella. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan perlakuan persentase penambahan bubuk bunga rosella berbeda beda yaitu 0%, 5%, 10% dan 15%. Hasil penelitian menunjukkan bahwa penambahan bubuk bunga rosella pada es krim berpengaruh nyata (P<0.05) terhadap nilai pH, kadar air, aktivitas antioksidan, kapasitas antioksidan, daya leleh dan karakteristik organoleptik. Penambahan bunga rosella tidak berpengaruh nyata (P>0.05) pada nilai aw dan overrun. Persentase terbaik ditemukan pada penambahan rosella perlakuan 5%., Ice cream is a semi-solid frozen food processed by milk which is made by going through various processes, namely pasteurization, homogenization, ripening of ice cream, stirring to form air cavities in the ice cream dough, and freezing in the refrigerator. Rosella flowers have high nutritional content and antioxidant compounds. The anthocyanin content in rosella flowers reaches 96 mg and vitamin C reaches 280 mg for every 100 g. Anthocyanins in rosella flowers are able to provide a protective effect against cardiovascular disease, including hypertension. This study aims to analyze the physicochemical, organoleptic and antioxidant activity of ice cream which was added with rosella flower. This study used a completely randomized design (CRD) with different percentages, namely 0%, 5%, 10% and 15%. The results showed that the addition of rosella flowers to ice cream had a significant effect (P<0.05) on the pH value, water content, antioxidant activity, antioxidant capacity, melting power and organoleptic characteristics. The addition of rosella flowers had no significant effect (P>0.05) on the aw and overrun values. The best percentage was found in the addition of 5% rosella treatment.
Keyword: antioxidant, ice cream, rosella flower, milk

Judul: Characteristics and Antioxidant Activity of Roselle Yoghurt Ice Cream
Abstrak: Es Krim yoghurt Rosela adalah inovasi produk yang menggabungkan susu, probiotik dari yoghurt, dan sifat antioksidan dari bunga rosela. Yoghurt, dengan bakteri asam laktat bermanfaat, mendukung kesehatan sistem pencernaan. Kandungan antosianin dalam bunga rosela meningkatkan tingkat antioksidan produk, melindungi dari radikal bebas dan stres oksidatif. Penelitian ini mengeksplorasi berbagai rasio yoghurt rosela dan es krim (20:80, 30:70, 40:60) untuk mengevaluasi sifat fisikokimia, kadar gizi, aktivitas antioksidan, dan karakteristik organoleptik. Dengan desain acak lengkap, analisis data melibatkan ANOVA, Uji Beda Nyata Terkecil (P < 0,05), dan uji Kruskal-Wallis untuk organoleptik. Hasil penelitian menunjukkan bahwa rasio 30:70 (P2) merupakan perlakuan optimal sesuai dengan preferensi konsumen terkait rasa dan kesehatan. Es krim pada perlakuan P2 menampilkan karakteristik fisikokimia optimal dan nilai sensori positif, dengan pH 5,47, total asam tertitrasi 0,74%, overrun 75,61%, dan daya leleh 26,98 menit, serta tingkat penerimaan sensori yang baik. Analisis kandungan gizi mengungkapkan bahwa perlakuan P2 mengandung 68,71% air, 1,35% abu, 1,82% lemak, dan 4,95% protein. P2 juga memiliki total aktivitas antioksidan terbaik, yaitu 137 µg/mL. Penelitian ini menunjukkan bahwa kombinasi yoghurt rosela dan es krim pada perlakuan P2 memiliki potensi untuk menjadi produk yang sesuai dengan preferensi konsumen serta memberikan manfaat kesehatan tambahan.
Keyword: Es Krim Yoghurt Rosela, Rosela, Manfaat Kesehatan

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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