Judul: Pengembangan yogurt probiotik dengan menggunakan isolat bakteri asam laktat asal manusia
Abstrak: Probiotik adalah suplemen makanan yang berisi mikrcba hidup yang sangat menguntungkan bagi inangnya (manusia dan hewan) karena dapat meningkatkan keseimbangan mikroflora usus (Fuller, 1989). Pangan probictik merupakan pangan (makanan/minuman) yang mengandung sejumlah bakteri hidup yang memberi efek yang menguntungkan kesehatan. Salah satu produk pangan probiotik yang cukup terkenal adalah produk susu fermentasi seperti yogurt, yakult, susu acidophilus, dan lain-lain. Produk probiotik yang tersedia umumnya menggunakan isolat komersial yang diisolasi dari manusia. Feses bayi umumnya digunakan sebagai sumber isolasi dengan pertimbangan bahwa bakteri hasil isolasi tersebut adalah bakteri yang telah mampu bertahan hidup dan menyesuaikan diri dengan kondisi di dalam saluran pencernaan. Evanikastri (2003) telah berhasil mendapatkan isolat bakteri asam laktat asal feses bayi, yang diuji karakteristik probiotiknya secara in vitro dan in vivo. Dari hasil penelitian tersebut diperoleh dua isolat BAL (Lactobacillus G3 dan Lactobacillus F1) yang memiliki potensi probiotik yang unggul untuk pengembangan yogurt probiotik, Penelitian ini bertujuan untuk menghasilkan produk yogurt probiotik yang memiliki viabilitas bakteri probiotik yang tinggi, yaitu minimal 10 CFU/ml, dan memiliki kemampuan bertahan dalam produk yang tinggi pula. Selain itu produk yogurt tersebut diharapkan dapat diterima dan disukai oleh konsumen. Pada penelitian ini yogurt dibuat dengan menggunakan bahan baku susu segar. Untuk menghasilkan yogurt probiotik dilakukan beberapa tahap penelitian yang mencakup (1) persiapan kultur starter, (2) penentuan jenis gula dan jenis flavor, (3) penentuan konsentrasi gula, (4) penentuan konsentrasi kultur starter, suhu, dan lama fermentasi, dan (5) pengujian perubahan mutu yogurt probiotk selama penyimpanan dingin. Hasil penelitian menunjukkan bahwa kultur starter dapat diperoleh dengan cara menginokulasikan kultur segar BAL dalam 10% susu skim steril. Kultur starter yang digunakan selanjutnya dalam pembuatan yogurt probiotik adalah Lactobacillus F1 karena yogurt yang dihasilkan memiliki rasa yang lebih dapat diterima konsumen dibandingkan yogurt yang dibuat dengan menggunakan Lactobacillus G3. Dari tahap penentuan jenis gula dan flavor terlihat bahwa penggunaan glukosa menghasilkan viabilitas dan pH yogurt probiotik lebih rendah, serta viskositas dan TAT yang lebih tinggi dibandingkan dengan sukrosa. Viabilitas Lactobacillus F1 tertinggi dihasilkan oleh yogurt probiotik yang dibuat dengan menggunakan sukrosa: dan flavor strawberry (1.8x10 CFU/ml), sedangkan viabilitas Lactobacillus F1 terendah dihasilkan oleh yogurt probiotik yang dibuat dengan menggunakan glukosa...
Keyword: yoghurt, lactobacilus cassei

Judul: Pembuatan Yogurt Sinbiotik Menggunakan Bakteri Asam Laktat Indigenus sebagai Pangan Fungsional Antidiare
Abstrak: Yoghurt is a product of fermented milk using lactid acid bacteria (LAB) as a starter. An indigenous probiotic LAB, Lactobacillus plantarum 2C12 and Lactobacillus fermentum 2B4, were applied in the making of functional synbiotic yoghurt with fructo-oligosaccharide (FOS) 5% as a prebiotic source. The aim of this study was to determine the best formula of functional synbiotic yoghurt as an alternative to protect human gastrointestinal against diarrhea. The best formula with the highest antidiarrheal effect was then applied with the addition of stabilizer and flavor to improve the product quality and consumer acceptance. The results showed that the synbiotic yogurt made from mixed culture L. bulgaricus, S. thermophillus, and L. fermentum 2B4 has the highest antibacterial effect in preventing Enteropathogenic Escherichia coli (EPEC) growth. Addition of 1.75% natural corn starch as a stabilizer produced optimum improvement in yoghurt consistency and minimize whey separation. Result of sensory evaluation indicated that the yoghurt with addition of 1% strawberry flavor and 0.1% vanilla flavor were ranked at first and second. Yoghurts could still good to consume after 15 days storage period at the refrigeration temperature (10oC).
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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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