• Journal of Biosystems Engineering
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• v.12 no.1
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• pp.39-44
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• 1987

Measurement methods of moisture content were compared with 7 dried vegetables (red pepper, onion, green onion, garlic, ginger, carrot and radish). The moisture contents of dried vegetables having different moisture contents were determined by atmospheric oven drying, infrared balance, vacuum oven and Karl Fisher methods. Vacuum oven and Karl Fisher methods gave the relatively agreed results and considered to give the accurate moisture content. Atmospheric oven drying and infrared balance methods resulted in higher moisture content than methods mentioned above, because of the thermal decomposition of solid. Calibration of the moisture data of atmospheric oven drying method into the vacuum oven data was undertaken. The thermodecomposable solid fraction was high in onion, radish, green onion and carrot, and was in the range of 8.0-11.7% of the total solid in these products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1226-1229
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• 1999

In order to investigate the harvest time for the production of high value added ark shell(Scapharca subcrenata) cultured at the south coast of Korea, the seasonal variations of proximate composition(mois ture, protein, fat, ash and glycogen) in the edible portions of ark shell were measured from December 1994 to December 1995. Moisture contents were the lowest in spring, but the highest in summer season being the spawning season of the S. subcrenata. The other hand, protein contents were a maximum in spring and minimum in summer. In June, just before the spawning season, fat and glycogen content was the highest, and ash content was little changed through a year. After spawning season, glycogen contents, showed decrement. In evaluating the seasonal variation of protein, moisture, and glycogen content in ark shell, the relationships of moisture protein content, moisture glycogen content and glycogen protein content show to be reverse.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.762-771
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• 2017

Predicting the amount and distribution of moisture content within wood allows calculating the various mechanical dynamics of the wood as well as determining the drying time. For boxed-heart wood with a large cross-section, since it is difficult to measure the moisture content of the interior, it is necessary to predict the moisture content distribution. This study predicted the moisture movement in boxed-heart red pine timber, during high temperature drying, by using the three-dimensional finite difference method for the efficient drying process. During drying for 72 h, the predicted and actual moisture content of the tested wood tended to decrease at a similar rate. In contrast, the actual moisture content at 196 and 240 h was lower than predicted because surface checking of the wood occurred from 72 h and excessive water emission was unexpectedly occurred from the checked and splitted surface.

• Journal of Microbiology
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• v.39 no.3
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• pp.195-201
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• 2001

The effect of moisture content an the reductive dechlorination of polychlorinated biphenyls and population dynamics of dechlorinating microorganisms was investigated in sediments spiked with Aroclor 1248. In sediment slurry with an overlying water layer, dechlorination ensued after a 4-week lag period and reduced the average number of chlorines per biphenyl from 3.91 to 3.15 after 48 weeks. In the sediments of reduced moisture content, however, dechlorination occurred after a lag period of 12 weeks and decreased the average number of chlorines per biphenyl to only 3.62, and the dechlorination rate was also slower. When the population size of dechlorinators, methanogens, and sulfate-reducing bacteria was determined by the most probable number techniques, however, no difference was found between the slurry and the low-moisture sediments, except for methanogens. The growth of dechlorinating populations coincided with the end of the lag period and they then increased by 3 orders of magnitude in two conditions. Specific growth rate of dechlorinators showed little difference between the slurry and the low-moisture sediments; however, growth yield was high in the sediments of reduced moisture content. The reduction of sediment moisture decreased the dechlorination rate and extent of PCBs but did not inhibit the growth of PCB dechlorinators.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.832-838
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• 2008

Diatomite, bentonite and zeolite were used as porous materials for fabricating hygroscopic panels. Moisture adsorption and desorption of porous materials were investigated and hydrothermal method was applied to fabricate panels. Cheolwon diatomite and Pohang zeolite showed excellent characteristics of moisture adsorption and desorption. These characteristics were caused by higher surface area and pore volume of porous materials. Correlation coefficient between surface area and moisture adsorption content of porous materials was 0.93. Moisture adsorption contents were influenced by surface area and pore volume of panels, and surface area more effected on moisture adsorption. Correlation coefficient between surface area and moisture adsorption content of panels was 0.86. Moisture adsorption content of panel with 10% Pohang zeolite was $180\;g/m^2$ and that of 10% Cheolwon diatomite was $170\;g/m^2$. Moisture desorption content of panel with 10% Pohang zeolite was $105\;g/m^2$. Moisture adsorption contents of panel with porous materials were higher than that of panel without porous materials.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.1
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• pp.23-32
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• 1997

The change in moisture content of moisture sensitive products in moisture-semipermeable packages was investigated for the purpose of predicting the shelf life of a product-package combination. A mathematical model, and a computer program based on the physiochemical properties of the product and the moisture permeability of the package was developed. The moisture content for products in moisture-semipermeable packages was determined under various environmental conditions and the results were compared with the predicted values by means of the simulation model. These experimental studies demonstrated that the prediction of the change in moisture content of packaged products over time by the simulation model is accurate, within a practical range of temperature and relative humidity values. The developed semi-empirical model is considered to have applications in industry, since it provides product shelf life information for a range of temperature and relative humidity conditions, with a limited number of experimentally obtained data points.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.14-18
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• 1994

In order to elucidate the interaction effect between temperature and moisture content on the oil expression of perilla seed, recovery of expressed oil (REO) and volumetric strain of pressed cake (VSPC) of both roasted and unroasted perilla seeds were observed at different temperatures of 30, 40, 50 and $60^{\circ}C$, and different moisture contents of 2.5, 4.5, 6.5 and 8.5% (w.b). And duration of press was 11 min and applied pressure was 50 MPa. At the low temperature REO and VSPC of roasted and unroasted perilla seed increased in high moisture content and at the high temperature those increased in low moisture content. But REO and VSPC at 8.5% moisture content were decreased without relation to temperature. From the analysis of variance between expression factors and REO and VSPC, temperature and moisture contents showed high significance. Also the interaction effect between temperature and moisture content was higher than temperature. In our experimental conditions, the highest interaction effect between expression factors was observed in the range of $2.5{\sim}4.5%$ of moisture content in all temperatures. The maximum REO of unroasted perilla seeds was observed as 84.4% at 2.5% of moisture content and $60^{\circ}C$, and that of roasted one was as 84.3% at 6.5% of moisture content and $30^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.17 no.3
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• pp.203-209
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• 2012

The effects of variable moisture content, screw speed and barrel temperature on the physicochemical properties of red ginseng powder extrudates were investigated. The raw red ginseng powders were processed in a co-rotating intermeshing twin-screw extruder. Primary extrusion variables were feed moisture content (20 and 30%), screw speed (200 and 250 rpm) and barrel temperature (115 and $130^{\circ}C$). Extruded red ginseng showed higher crude saponin contents (6.72~7.18%) than raw red ginseng (5.50%). Tested extrusion conditions did not significantly affect the crude saponin content of extrudates. Increased feed moisture content resulted in increased bulk density, specific length, water absorption index (WAI), breaking strength, elastic modulus and crude protein content and decreased water solubility index (WSI) and expansion (p<0.05). Increased barrel temperature resulted in increased total sugar content, but decreased reducing sugar content in the extrudate (p<0.05). Furthermore, increased barrel temperature resulted in increased amino acid content and specific length and decreased expansion and bulk density of extrudates only at a higher feed moisture content. The physicochemical properties of extrudates were mainly dependent on the feed moisture content and barrel temperature, whereas the screw speed showed a lesser effect. These results will be used to help define optimized process conditions for controlling and predicting qualities and characteristics of extruded red ginseng.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.772-779
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• 1989

The effects of screw speeds and moisture contents on the physical properties of texturized extrudate from isolated soy protein were examined by using a single-screw extruder. The screw speeds and moisture contents tested were in the range of 122-334 rpm and 20-35%, respectively, and die temperature were $90-145^{\circ}C$. The texturization characteristics such as nitrogen solubility index, integrity index, chewiness, density, rehydration ratio, and lightness after rehydration were appeared to be influenced by screw speed and moisture content. As the screw speed increased and moisture content decreased, die temperature, nitrogen solubility index, integrity index, lightness before and after rehydration were increased, while chewiness, density, water content of final extrudate wee decreased. The rehydration rate was changed drastically at the feed moisture content of 30% in particular. As the moisture content decreased, the air cell size became large and its number was increased. The effects of interaction between screw speed and moisture content of raw materials on the extrudate characteristics were tested by the analysis of variance.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.582-592
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• 1995

To measure rheological properties of the starch dough, an Extrusion Capillary Viscometer(ECV) cell was self-made and attached to Instron machine(Model 1140). Apparent viscosities of corn and waxy corn starch doughs were measured and their gelatinization degrees were determined by enzymatic analysis. When corn and waxy corn starch doughs with $36{\sim}52%$ moisture content were heated at $60{\sim}100^{\circ}C$, come-up time of the cold point of doughs decreased from 220 sec to 140 sec with increased in the moisture content. In the measurement range of $36{\sim}52%$ moisture content and $60{\sim}100^{\circ}C$ heating temperature, both corn and waxy corn starch doughs showed pseudoplastic flow behaviors. At the same shear rate, both shear stress and viscosity of starch dough decreased as the moisture content increased. At the moisture content above 44%, the shear stress and viscosity of starch dough decreased as the heating temperature increased from $60^{\circ}C\;to\;70^{\circ}C$, but increased as the heating temperature increased from $80^{\circ}C\;to\;100^{\circ}C$. When the moisture content increased and heating temperature, the gelatinization degree of starch dough increased from about 10% to about 62%. The gelatinization degree of waxy corn starch dough was $15{\sim}20%$ higher than that of corn starch dough under the same gelatinization conditions. The effects of moisture content on the viscosity of starch dough were examined by Arrhenius equation. As the moisture content increased, viscosity of starch dough decreased. But the effect of moisture content was greater in the range of $80{\sim}100^{\circ}C$ than in the range of $60{\sim}70^{\circ}C$ heating temperature.