• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.640-645
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• 1995

Job's-tears(Coix lachryma-jobi L. var. Ma-yuen Stapf) seeds were processed to flakes by soaking, heat treatment, intermediate-moisture drying, flaking, drying, and cooking. Some functional properties of job's-tears flakes subjected to varing degree of heating were characterized by specific volume, texture, water absorption index(WAI), water solubility index(WSI), and viscosity. As degree of gelitinization increased within the intermediate range of $60{\sim}70%$, steam-cooked Job's-tears demonstrated appropriate rheological properties for further processes, resulting in increased specific volume and decreased breaking strength. However, excessive heat treatment rendered Job's-tears undesirably sticky for flaking, which caused adverse effects on the functional properties of flakes such as specific volume and breaking strength. Increasing steaming time$(5{\sim}30\;min)$ caused an increase in WAI and WSI values. Apparent viscosity of powdered flakes was increased with the extent of gelitinization as a function of heat processing. Viscosity of powdered flakes determined using the amylograph increased with the degree of heating applied to Job's-tears at low pasting temperatures, accompanied by a decrease in maximum viscosity as the pasting temperature increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.433-438
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• 2004

This study was conducted to develop a sweet pumpkin to intermediate materials for various processed foods and dried food having high quality. Factorial experiment design with three variables having three levels was adapted and response surface methodology was used to determine optimum conditions for osmotic dehydration of sweet pumpkin. The moisture content, weight reduction, moisture loss and solid gain after osmotic dehydration increased according to increasement of immersion temperature, concentration and time. The effect of concentration was more significant than that of temperature and time at given conditions. Sugar concentration and vitamin C content increased in accordance with increasement of immersion temperature, concentration and time during osmotic dehydration. Hardness was increased by increasing immersion time. The regression models showed very significant values and high correlation coefficients (R2) above 0.91, excepting hardness. The optimum condition for osmotic dehydration was 23$^{\circ}C$, 52$^{\circ}C$Brix and 80 min at the constricted conditions such as 60∼70% moisture content, above 3 mg/100 g vitamin C and more than 10 kg/$\textrm{cm}^2$ hardness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1573-1579
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• 2004

This study was conducted to develop intermediate material for new processed food from sweet pumpkin. Osmotic dehydration was carried out as pretreatment before drying. After the sweet pumpkins were pretreated under optimized osmotic dehydration conditions, they were dried by three drying methods (hot air drying, vacuum drying and cold air drying). The moisture contents of dried sweet pumpkin products by osmosis treatment (sucrose) and hot air drying, vacuum drying, and cold air drying were 14.48, 14.09 and 13.87%, respectively. Cold air drying preserved more vitamin C content and showed lower color difference than hot air drying and vacuum drying. As a result of microscopic analysis, cold air dried sweet pumpkin was observed regular tissue, while hot air and vacuum dried sweet pumpkins were observed a cell collapse following the loss of water.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.303-309
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• 1988

The heat generation at the start-up period of an autogeneous single screw extruder was determined with various feed materials, die structure and operational conditions. The highest heat generation rate was observed with defatted soybean meal, while the lowest value was obtained with rice flour, and wheat and barley flour showed the intermediate rate. As the moisture content of the flour decreased and the screw speed increased, the electric power requirement and heat generation rate increased. The temperature at compression section increased with the decrease in the particle size. The same effect was also observed as breaker plate was installed. The optimum operation was established as the temperature profile was maintained in decreasing order of metering section, die and compression section.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.328-333
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• 2019

The proximate composition and mineral contents of 18 subtropical fish species caught off the coast of Jeju Island, Korea were determined. The mean moisture content was highest (78.0%) in the eight species of lean fish, lowest (72.6%) in the four species of medium-fat fish, and intermediate (75.4%) in the six species of low-fat fish. The lipid content was in the order of medium-fat fish > low-fat fish > lean fish. The protein content ranged from 17.7% to 18.9%. The mean macro-mineral contents in the 18 species were 290.2 mg/100 g edible portion K, 146.6 mg P, 113.5 mg Na, 67.2 mg Ca and 38.3 mg Mg. The mean value of micro-mineral contents were 2.1 mg Fe, 1.7 mg Cu and 1.5 mg Zn. These results suggest that subtropical fish from Jeju Island are good sources of protein, lipid and minerals.

• The Korean Journal of Food And Nutrition
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• v.33 no.5
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• pp.588-597
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• 2020

This study was conducted to secure basic information for corn processing by comparing the quality characteristics according to maize cultivars and kernel types (dent, intermediate, flint-like). As a result of analyzing 15 cultivars, a range of measurements were observed: 100-kernel weight, 22.89~35.63 g; moisture, 7.57~8.42%; crude protein, 8.46~11.45%; crude lipids, 3.26~4.83%; Hunter's L-value, 83.70~86.79; a-value, 2.61~5.49; b-value, 22.01~28.15; and total carotenoids, 6.74~17.07 ㎍/g. Significance among the cultivars was shown in all quality characteristics (p<0.001), but the significance among the kernel types was found only in crude protein (p<0.005), crude fat (p<0.001), and Hunter's L-value (p<0.05). The hardness of maize was decreased proportionally to the soaking time for all maize cultivars (p<0.001). In particular, with the same soaking time for different kernel types, the hardness difference was shown in the order of flint-like > dent ≒ intermediate. It was confirmed that the decrease in the hardness of flint-like kernel of close to that of hard-type starch was slowed compare dent and intermediate kernels. So it is expected the some characteristic of kernel types will contribute to the appropriate customized use of the developed cultivars.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.632-639
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• 2018

To develop the high-value added seafood products from a regional speciality seafood, the seasoned dried pen shell Atrina pectinata adductor (SDPA) and seasoned smoke-dried pen shell adductor (SSPA) samples were prepared, and their optimal processing conditions, quality metrics, and shelf-life characteristics were examined. SDPA and SSPA samples were produced by thawing of frozen pen shell adductor, and cutting it into 6-7 mm slices, hot-air drying ($60^{\circ}C$, 20 min) or smoking ($110^{\circ}C$, 20 min), seasoning ($4^{\circ}C$, 12 h) with seasoning powder (60% sorbitol, 15% sucrose, 16% salt and 9.0% monosodium glutamate), hot-air drying ($60^{\circ}C$, 3 h), torching, vacuum-packaging in a laminated plastic film bag, heat treating with hot-water ($85^{\circ}C$, 15 min), and cooling. The moisture content of SDPA and SSPA samples was 44.5 and 43.0%, respectively, and the water activity was 0.845 and 0.842. The total amino acids in SDPA and SSPA samples were 20,986.8 and 21,312.4 mg/100 g, respectively, and the major amino acids in both products were aspartic acid, serine, glutamic acid, proline, glycine, alanine, valine, leucine, phenylalanine, lysine and arginine. The primary minerals were Na, S, K and P. Incubating tests indicated that the quality of SDPA and SSPA samples was maintained for 30 days of storage.

• Food Science of Animal Resources
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• v.36 no.3
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• pp.326-334
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• 2016

This study was carried out to develop jerky product utilizing spent hen meat. Manipulation of water activity (a_w) of semi-dried meat with the addition of humectants (glycerol and sorbitol at the concentration of 0, 10, and 15%) and roasting process were applied to enhance quality of jerky product. After spent hen meat was ground, formulated, reformed and then dried in convection oven at 85℃ for 2 h followed by 60℃ for 1 h, all jerky samples showed values of a_w ≤0.85 with total aerobic bacteria, yeast and mold and Staphylococcus aureus counts were reduced to undetectable levels. Moreover, the results showed that the 15% glycerol added jerky showed superior quality, indicated by the lowest a_w, low protein aggregation as evaluated by sorption isotherm and the lowest shear value as compared to sorbitol added and control samples (p<0.05). Regardless effect of humectant, roasting could improve the quality of the jerky via enhanced sensory attributes by increasing color, appearance, flavor and overall acceptability scores (p<0.05). Therefore, spent hen meat could be used as a potential raw material for jerky in which soft product texture obtained by the addition of glycerol and intense flavor resulted from roasting process after drying, leading to sensory acceptance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.619-626
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• 2012

This study investigated the food quality characteristics of mottled skate Raja pulchra including the proximate composition, taste, color, flavor and texture as affected by area caught (Heuksando and Daecheongdo), sex and fish weight (heavy, intermediate and light grades). Based on viable cell counts, all of the mottled skates studied remained fresh. The moisture and protein contents of the mottled skate did not differ by the area caught and fish weight, but differed by fish sex. The taste of mottled skate was affected only by fish weight. The texture of the mottled skate differed according to fish sex and fish weight. The odor intensity did not differ for the three parameters.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.475-481
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• 1984

Estimation of the penetration rate of humectants has been considered to be important in effective control of food processing when intermediate moisture food is manufactured by the moist-infusion method. In this study, when shark (Isurus glaucus) muscle was soaked in four common humectants (sucrose, sorbitol, glycerol, and propylene glycol), the equation of their penetration rate was drawn as a function of time using high performance liquid chromatography analysis. Penetration rates increased with soaking temperatures and decreased inversely with molecular weights of humectants. The penetrated amounts for 10% humectant solution reached about equilibrium after soaking for 10 hours and for 30% humectant after soaking for about 7 hours. In consideration with the penetration rate of the sample soaked in 10% humectant and complex solution of each 10% humectant, little difference was found between them. When the sample was soaked in 10% humectant and 30% humectant, it seemed to be able to apply the following regression equation to estimate the penetrated amounts: M = a log (c.t)+ b where M = penetrated amounts; c = concentration of humectant; t= soaking time; a, b = constant and c.t should be within $10^3\;-\;4{\times}10^4$.