Judul: Kombinasi Konsentrasi dan Lama Perendaman dalam Larutan CaCl2 untuk Mempertahankan Mutu Daging Buah Mangga Kupas Utuh
Abstrak: Mangga adalah buah musiman yang berlimpah saat panen rауа. Сага panen dan kondisi iklim yang tidak baik membuat buah mangga berpenampilan kurang menarik yaitu bergetah dan ada bercak-bercak hitam pada permukaan kulit buah yang tidak dapat dihilangkan dengan proses pencucian biasa. Agar buah mangga tetap mempunyai nilai jual yang tinggi, maka dilakukan pengupasan bagian kulit. Kelemahan dari buah terkupas adalah cepat menurun mutunya. Untuk mempertahankan mutu buah mangga terkupas maka dilakukan penelitian dengan tujuan menentukan kombinasi lama perendaman dan konsentrasi CaCl2. Buah mangga indramayu yang digunakan dalam penelitian diperoleh dari pedagang pengumpul yang ada di Pasar Bogor. Perlakuan yang diteliti adalah kombinasi lama perendaman 1 dan 5 menit dengan konsentasi CaCl2 0.99% dan 3.85%. Secara umum buah mangga yang diberi perlakuan CaCl₂ pada suhu 13 °C mampu mempertahankan mutu buah sampai hari ke-7 sedangkan pada suhu ruang bertahan sampai 3 hari. Perendaman buah mangga terkupas dalam larutan CaCl₂ 3.85% selama 5 menit (M4R5) pada suhu 13 °C memiliki nilai kekerasan yang baik dan warna buah cerah kekuningan….
Keyword: CaCl2, Dipping, Mangoes, Quality, Harvest handling, Dipping time, CaCL2 concentration, Ambient storage, Yellowish color

Judul: Kajian Kombinasi Hot Water Treatment (HWT) dan CaCl2 terhadap Mutu dan Umur Simpan Mangga Varietas Gedong Gincu (Mangifera indica, L.)
Abstrak: Mango cv. gedong gincu is one of tropical fruit that has been a long time cultivated and have the commercial potention in Indonesia, but the export volume of this fruit is lower than the production volume. This is because of the quality, certification and limited of product supply. To increase the amount and competitivness of mango cv. gedong gincu’s export, there are some postharvest treatment, one of them is combination of hot water treatment (HWT) and CaCl2. General purpose of this research was to maintain tropical fruit quality starts from postharvest handling in the suply chain that already exist using the combination treatment. The research was divided into 4 main groups: preparation, treatment, observation and analysis the data. Through the research, treatment of HWT was significantly influencing the respiration rate, hardness, total soluble solids, weight losses and total acid; CaCl2’s soaking was not too influencing the changes of the fruit quality; and the combination treatment was significantly influencing the respiration rate, hardness, color changes and total acid of the fruit. From the visual, observation of quality changes and organoleptic test, sample of HWT 55oC 15’ (CaCl2 20’, 40’, 60’) have the most significant different value compared to another treatment. The longest storage period of the mango was sample with HWT 35oC; CaCl2 60’ and HWT 45oC 40; CaCl2 20’ that could be stored for 14 and 15 days based on respiration rate and total acid. The shortest storage period was sample with HWT 55oC 15’ (CaCl2 20’, 40’, 60’), 3 days.
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Judul: Pengaruh vaksinasi terhadap dinamika populasi pada model SIR (Susceptible-Infected-Recovered)
Abstrak: SIR model can be used to model the spread of diseases in a closed population based on certain assumptions. In this research, the SIR model is formulated by including the factor of vaccination. As the result, the model has been shown to have two equilibrium points, i.e. disease free and endemic equilibrium. A simulation study is carried out to illustrate the model. The results show that some equilibrium points are asymptotically stable. Moreover, a minimum level of vaccination has been defined. For the vaccination level less than the minimum level, increase in the vaccination level results in decrease of the proportion of infected individuals in the corresponding equilibrium point. On the other hand, for the vaccination level greater than the minimum level, increase in the vaccination level results in decrease the proportion of susceptible individuals in the corresponding equilibrium point. Furthermore, when vaccination level is greater than the minimum level, it is found that the time needed for the disease to extinct is shorter.
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