Judul: Karakteristik Dendeng Batokok dari Daging Sapi dan Kerbau dengan Beberapa Bahan Pengasap
Abstrak: Dendeng batokok is one of traditional jerked meat in Indonesia treated traditionally with smoked and pounded and using raw material produced at the local level and potential to be developed because it has a distinctive flavor. It needs to be introduced further into one of the alternative meat products. The production process is traditionally and often produce products that vary in quality, it is necessary for standardization related to the process of making dendeng batokok, so that would be generated products with a more homogeneous quality and safety. The objective of this study was to study the characteristics of dendeng batokok that made from beef and buffalo meat as raw materials and the use of coconut shell, medang sawdust and rice husk as smoke material. Smoking was conducted during each 30, 60 and 90 minutes. The research was conducted in three stages; 1) determining of selected smoking time, 2) determining of selected smoke materials, 3) flavor analysis of dendeng batokok. Parameters observed during research were organoleptic attributes (colour, texture, aroma and taste), quality changes of dendeng batokok with physical, chemical and microbiology variables (pH, water activity, hardness, moisture content, protein, lipid, total plate count, S. aureus, molds) and flavor volatile components. The experimental design used complete randomized design (CRD) with three replications. Nonparametric data of organoleptic tests processed statistically by Kruskal-Wallis method. Parametric data physical, chemical and microbiological variable analyzed by t test (Steel and Torrie 1993). Data processing using the program Statistical Analysis System (SAS) 9.1 and Minitab 15 version. The results of this study indicate that; 1) the selected of dendeng batokok with the highest average value of beef and buffalo meat are 60 minutes for coconut shell smoking during, 90 minutes for medang sawdust smoking medang and 90 minutes for rice husk smoking, (2) the use of beef and buffalo meat with smoking coconut shell, medang sawdust and rice husk showed no real difference on organoleptic characteristics, (3) physical, chemical and microbiological characteristics of dendeng batokok in this research in general is still quite good until 7 days of storage except for mold variable with rice husk smoking, (4) beef and buffalo meat have the same characteristic value to be used as raw material for dendeng batokok processing, (5) medang sawdust can be used as alternative smoke materials for dendeng batokok processing from beef and buffalo meat.
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Judul: Study Of Smoking Method In The Production Of Dendeng Batokok
Abstrak: Dendeng is a special dried meat product of Indonesia, which is processed by slicing the meat slightly followed by curing and drying processes. In West Sumatera, there is a well-known traditional meat product called dendeng batokok, which is processed specially using local raw materials and has unique flavor. Unfortunately, the shelf life of this meat product is only about two days. The spoiling of meat product can be caused by microorganism activity especially bacteria, enzyme activity, temperature, oxygen level and storing. Due to this limitation of dendeng batokok shelf life, it is needed to introduce a preserving method to maintain the quality of the product. The main problems found in the process of dendeng batokok production by smoking process are: 1) traditionally smoking process (direct smoking method), using fireplace and cormorant in opened space that can cause smokes lost in the air and unabsorbed into the meat, this will influence the quality, appearance and color of the meat, 2) time and temperature of smoking is varying, with smoking time between 1 to 7 hours, and unstable temperature between 25 to 75 oC, effecting high level water content, which is between 50 - 65% and effecting shelf life, 3) the variation of meat brooding time (about 30 – 60 minutes), flavor and salt that can influence texture, aroma and color of the product. 4) sanitation and hygienic during the making process are not yet noticed well so that the product might be contaminated by microbe. Thus, to cover the problems found in traditional smoking method, this study was attempted to improve the process and the smoking technology (indirect smoking method) of dendeng batokok by introducing smoking equipment and appropriate smoking temperature so that it could improve the quality and shelf life of the product. The result of this research showed that, by using direct smoke method, the best product was resulted at 6 hours of smoking time and 61-70oC of smoking temperature with high organoleptic scores of color, aroma and flavor (4,3; 4,7; 4,9), and has 26,98%d.b of water content; 0,60 of aw; 17,40%d.b of protein, 9,42%d.b of fat; 0,47kg/cm2 of hardness; 0,38 mg malonaldehid/kg; 9,04mg/kg of formaldehyde; 34,6 x 107 CFU/gr of TPC. By using indirect smoking method, the best product was resulted at 9 hours of smoking time and 61-70oC of smoking temperature with high organoleptic scores of color, aroma and flavor (5,3; 4,5; 4,8) and has 18,13%d.b of water content; 0,57 of aw; 18,77%d.b of protein, 8,52%d.b of fat; 0,48 kg/cm2 of hardness; 0,38 mg malonaldehid/kg; 9,26mg/kg of formaldehyde; 70,0 x 106 CFU/gr of TPC. It was also obtained from this research that by using indirect smoking method, coliform bacteria did not emerge after 15 days of storage while direct smoking method did. Finally, it can be concluded that indirect smoking method has a better result compared to direct smoking method.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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