• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.10-17
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• 2000

This work presents an investigation of aerodynamic characteristics of fuel spray injected from a high pressure hollow cone swirl injector into a constant volume chamber. Laser tomography visualization was used to interrogate the fuel and air mixing characteristics and the effect of chamber pressure and temperature increase was analyzed, Preliminary results on spray development showed that mixing effect tends to increase with the increase of injection pressure and chamber gas pressure yielding a decrease of spray penetration and an attenuation of well-defined vortex structure. Topological analysis of the spray structure has been performed to initiate the understanding of mixing and vaporization process. For the present experimental conditions fuel injection pressure and chamber gas pressure appear as the dominant factors which govern the transient mixing characteristics. Moreover spray atmixation characteristics are improved by increasing chamber gas temperature.

• Food Science and Preservation
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• v.24 no.2
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• pp.246-253
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• 2017

This study was conducted prepare spray-dried powder using pumpkin sweet potato hydrolysates and examine the physicochemical properties of the powder. The insoluble dietary fiber and soluble dietary fiber of the pumpkin sweet potato treated by enzyme were 4.17% and 2.07%, respectively. The spray-dried pumpkin sweet potato hydrolysates was manufactured via spray-drying with different forming agents: i.e., pectin 0.1%, 0.5%, 1%, and 2.0%. The moisture contents and total starches of the spray-dried powders were approximately 1.68-2.46 and 45.32-46.51%, respectively. The color of the L and a value decreased, and that of the b and ${\Delta}E$ value increased. The particle size and outer topology of the spray-dried powders were $37.17-42.32{\mu}m$, and its shape was generally globular. The water absorption index of the spray-dried powder (1.74-1.91) was lower than that of the freeze-dried powder (2.15). The water solubility index of the spray-dried powder, 80.75-87.61%, was higher than that of the freeze-dried powder (70.47%). The adhesion values of spray-dried powder to epithelial HT-29 cells were 2.66-6.18% of the initial cell counts, whereas freeze-dried powder showed lower adhesive ability (1.79%). The in vitro human digestibility in the spray-dried powder was 70.09% which is very effective in digestion.

• Journal of Chitin and Chitosan
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• v.22 no.2
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• pp.110-117
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• 2017

This study was conducted to examine the physicochemical properties and hot air-dried and spray-dried powders process of sweet potato and steamed sweet potato. The moisture and the total starch contents were 1.66~2.19% and 52.65~57.42%, respectively. The total starch contents increased during process steaming. The water absorption index of the spray-dried powders (0.97 and 2.03) was lower than that of the hot air-dried powders (2.12 and 4.71), and the water solubility index of the spray-dried powders (83.83 and 86.95%) was higher than that of the hot air-dried powders (68.40 and 81.21%). The particle size and outer topology of the spray-dried powders were 46.18 and $65.53{\mu}m$, and its shape was generally globular. In the DSC analysis of this study, the $T_o$ of the spray-dried powders (64.40 and $67.80^{\circ}C$), $T_p$ of the spray-dried powders (74.40 and $78.20^{\circ}C$), and $T_c$ of the spray-dried powders (81.10 and $81.60^{\circ}C$) was higher than that of the hot air-dried powders. The solubility contents of the spray-dried powders (68.21 and 80.73%) was lower than that of the hot air-dried powders, and the swelling power contents of the spray-dried powders (14.79 and 15.35%) was higher than that of the hot air-dried powders. The amylose contents of spray-dried powders (11.67 and 12.51%) was lower than that of the hot air-dried powders. The soluble dietary fiber contents of spray-dried powders (1.34 and 2.02%) was higher than that of the hot air-dried powders.

• Food Science and Preservation
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• v.22 no.2
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• pp.225-231
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• 2015

This study was conducted to examine the physicochemical properties and micro-encapsulation process of rice fermented with Bacillus subtilis CBD2. The viable bacterial cell, pH, and amylase activity of the rice liquid culture were 7.61 log CFU/mL, pH 5.08 and 159.43 units/mL, respectively. The micro-encapsulated rice liquid culture was manufactured via spray drying with different forming agents: i.e., alginic acid 1.0% and chitosan 0.3%, 0.5%, and 1.0%. The moisture contents of the spray-dried powders were approximately 2.90~3.68%. The color of the L and a value decreased whereas that of the b and ${\Delta}E$ value increased. The particle size and outer topology of the spray-dried rice liquid culture were $48.13{\sim}68.48{\mu}m$ and globular, respectively. The water absorption index of the spray-dried powder (2.40~2.65) was lower than that of the freeze-dried powder (2.66). The water solubility index of the spray-dried powder (9.17~10.89%) was higher than that of the freeze-dried powder (7.12%). The in vitro dissolution was measured for five hours in pH 1.2 simulated gastric fluid, and pH 6.8 and pH 7.4 simulated intestinal fluids, using a dissolution tester at $37^{\circ}C$ with 50 rpm agitation. The amylase survival in the fermented rice was 85.93% through the spray-drying and it was very effectively controlled.