Judul: Perubahan Konsentrasi Larutan Gula pada Dehidrasi Osmotik Irisan Mangga (Mangifera indica L.) dan Pengaruhnya Terhadap Kebutuhan Daya Pengadukan
Abstrak: During osmotic dehydration, water leaving the product may dilute the osmotic solution, especially for conditions having low product solution ratio. The main objectives of this study were to obtain the characteristic of sugar solution concentration during osmotic dehydration of mango and its effect on stirring power requirement. Solution concentration used in this study was 61o brix. Three level of solution temperature, i.e 30 oC, 40 oC, 50 oC and three levels of stirring speed, i.e 100 rpm, 300 rpm and 500 rpm were used as the process variables. Stirring speed and high temperature solution will increase the water loss, while the final moisture content of the sample will be lower. Highest water loss by 70% and the lowest final moisture content of 35.3% wb occur at 30oC temperature treatment and stirring speed 500 rpm. Solid gain at high stirring speed increased temperatures 30oC (4.59%), 40oC (7.92%) and 50oC (11.9%), while the solid gain with medium and low stirring speed did not increase. High stirring speed (500 rpm) at a temperature of 30oC solution, 40oC and 50oC produces Reynolds number greater than the low (100 rpm) and medium (300 rpm) stirring speed for 8 hours. The decresing osmotic solution concentration due to the water leaving the mango during the osmotic process provided the reduction solution viscosity. These conditions caused in the stirring rotation speed increased, so the need for stirrer motor power decreased during the osmotic dehydration process.
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Judul: Karakteristik Dehidrasi Osmotik Irisan Mangga Cengkir (Mangifera indica L.) pada Berbagai Ketebalan dan Konsentrasi Larutan Gula
Abstrak: Osmotic dehydration is one of the alternative methods commonly applied on pre-drying fruits like mango. The objectives of this study were to obtain effect of sugar concentration and thickness of mango slice on changes of osmotic dehydration characteristic and physical properties changes of mango slice in osmotic dehydration using temperature 30ºC, and in osmotic dehydration at room temperature for 48 hours. Thickness of mango slice that used were 0.5 cm, 1 cm, and 1.5 cm, while concentration of osmotic solution were 30ºBx, 45°Bx and 60°Bx. Observations were carried out for 6 hours at 30ºC and 48 hours at room temperature. High concentration of osmotic solution increased WL, but high solid gain trend in medium concentration of osmotic solution (45ºBx) was found. Increasing of concentration osmotic solution increased shrinkage, WR, density and porosity. Decreasing of thickness mango slice increased value of WL, WR and shrinkage. While the thickness of mango slice didn’t affect SG value, density and porosity of sampel increased during the process or osmotic dehydration. The best sample was thickness 0.5 cm using 60ºBx osmotic solution. It has lower water content, high value of WL, and lower SG value. Azuara modeling can be used as data validation WL obtained of R2 values 0.954 to 0.993.
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Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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