Judul: Kemampuan Dadih Susu Sapi Menghambat Enterobacteriaeeae Secara In Vitro
Abstrak: Ddih is a saditional fermented milk from West Sumatera. instead of BufMoes milk, cows milk were used in this research. Using ktobaeillus planfamm as a dadih starter (concmtration 3,4,S %) d incubated for 48 hours at room tmpmtm. Obmtion of rladi)l bgin hm the lirst day of this poduct until 7 days aud its still stored at room temperatm. The ability of suppresing Enterobueferiaceae activity is abed by using mcherichia coli, SaImoneIZa tphimwim and Shigellaflaxneri (lo6 CFU/ml) in Nutrient Agar and challenge with dad& 3%, 4% and 5% (50 -11). Tetracylim, chlommpheniml and a p b paper disc are used as control. Obsewation of dad& quality by using Storch test, pH, acidity (titdon) and orgaaaleptic. Dadih of starter concentdon SY0-first day has the biggest inhibitation m e (17.42 mm) to E. coli, fblIowed by S. @phimwium (9.39 mm) and X Pexneri (8.88 mm) by dadih at concentration 5%- W da . Range of pH showed between 4.84 to 4.14 and the acidity btween 114.67 % to 365.67 %. The sensitivity test to antibiotilra was fourd by E cdi (ATCC 38218) with a resistance to chloramphenicol. Redt of the o~olep-tic test, respon of the panelist showed no differences on liked vdw between various concentration For the befit of the cwsumers health, dadih were good until the third day.
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Judul: Pengaruh Penambahan Bahan Tambahan Pangan (BTP) yang Dikombinasikan dengan Bakteri Asam Laktat (BAL) terhadap Karakteristik Dadih Susu Sapi
Abstrak: A decrease in productivity of buffalo milk leads us to seek the other solutions to change it as raw material of dadih. Productivity of cow's milk which abundant makes it potential as an alternative to buffalo milk. The different characteristics, both physically and chemically between them causes the characteristic of dadih is also different. Fortification the food additives that combined with lactic acid bacteria in cow's milk, is expected to improve the characteristics of dadih. The purpose of this study was to determine the best combination of the use of food additives and lactic acid bacteria ,which can produce dadih with good characteristics. Based on the results of test determining the best concentration of cow's milk as raw material for dadih so cow’s milk need be evaporated until 50% (v / v). The best concentration of food additives is 100 ppm for enzyme papain, the enzyme renin 2 ppm, and crude enzyme extract of Mucor sp. 0.5 ppm. Analysis of physical, chemical, and microbiological showed that the best treatment is the enzyme renin 2 ppm in combination with 3% Lactobacillus casei. Dadih from this treatments has a viscosity 2278 cP; pH 5,63; total acid value 0,56%; water content 75,03%; protein content 6,80%; fat content 3,35%; carbohydrate content of 13,21%;and total BAL 6,90 x 1010 cfu / gram. The results also showed that all treatments produced dadih with total BAL > 1010 cfu/gram, so that these dadih can classified as a probiotic food. Hedonic test showed that the addition of the enzyme renin 2 ppm and 3% Lactobacillus casei has advantages in terms of taste (3,24), aroma (3,20), texture (3,60), and public acceptance (3,32). As for the color parameters, the treatment was scored still quite high (3,48).
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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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