Judul: Optimasi Penggunaan Tepung Komposit Jagung dan Ubi Jalar dalam Pembuatan Kukis
Abstrak: Corn and sweet potato have been known as local resources in Indonesia. Composite flour consisted of corn and sweet potato flour could be used to replace wheat flour in cookies production. The aim of this research was to obtain optimum formula and process parameters in cookies production using composite flour. Wheat flour could be totally replaced by composite flour which were made from 77.54% of corn flour and 22.46% of sweet potato flour. Optimum baking parameters were 139°C for 18 minutes. The organoleptic score of the cookies was between 5.89 (like slightly) and 7.18 (like moderately). Proximate analysis showed that cookies contained 4.55% of water, 1.65% of ash, 5.97% of protein, 64.40% of carbohydrate (by difference), and 23.43% of fat.
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Judul: Optimasi Formula dan Proses Pembuatan Muffin Berbasis Substitusi Tepung Jagung dan Ubi Jalar Kuning
Abstrak: Nowadays, the high domestic consumption of wheat-based bakery product has increased the amount of imported wheat flour in Indonesia. Food diversification using local resources becomes one of the solutions to reduce the cost associated with imported wheat flour. The objective of this research is to make composite flour (consists of corn flour and sweet potato flour) substituted muffins that is sensory acceptable by consumers. This research is divided into 3 stages namely formula optimization using mixture design technique, process optimization using response surface methodology, and final product analysis, which consists of texture analysis and proximate analysis. Hedonic rating test is carried out to collect the response from 70 untrained panelists. The results showed that the formula with 4% wheat flour, 86% corn flour, and 10% sweet potato flour was selected as optimal formula while the process with 39 minutes of baking time and 158°C of baking temperature was chosen as optimal process. The hardness score of muffin produced from optimal formula and process is equivalent to 107.3 gf. The final product contained 18,84% moisture, 1.48% ash, 4.78% protein, 18.23% fat, 56.67% carbohydrate, and 0.26% crude fiber.
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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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