• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.973-980
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• 2000

This study was conducted to evaluate the quality of the cold air dried anchovies (CA), and compared with those of sun-dried anchovies (SA) and hot air dried anchovies (HA). Peroxide value increased, while ratio of percentage of (20:5+22:6) to that of 16:0 decreased during boiling and drying. The extents of change were CA>SA>HA in the order. In the case of CA, lightness was higher, but redness, yellowness and degree of browning was lower than in SA and HA. From the results of lipid properties, color test and sensory evaluation on color and rancidity odor, lipid deterioration was the lowest in CA of all boiled dried anchovy. Favorite properties such as a hot-water soluble nitrogen content and sensory evaluation on color and appearance of CA was superior to that of SA and HA. The nutritional properties (total amino acid contents, mineral contents and fatty acid compositions) of CA was similar to that of SA, but was superior to that of HA. Consequently, CA was recognized as a boiled dried anchovy with the most quality.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.72-79
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• 2008

In this study, changes in the physicochemical properties and functional components of uncooked foods, including carrots, cabbage, shiitake (Lentinus edodes) and white button (Agaricus bisporus) mushrooms, sea mustard, and laver treated with electrolyzed water were investigated. No changes were observed in the primary compositions of any of the materials that were hot air- or freeze-dried after being treated with electrolyzed water. The lightness (L), redness (a), and yellowness (b) values of the carrots, shiitake, and laver were not affected by drying, while changes did occur in the cabbage (L-, a-, and b-values), mushrooms (a-value), and sea mustard (b-value) specimens that were hot air- or freeze-dried following the treatments with electrolyzed water. The dietary fiber contents of all the materials increased when they were hot air-dried. Vitamin C content decreased when the samples were treated with alkalic electrolyzed water. No changes occurred in the lectin, $\beta$-carotene, or total phenolic compound contents after the electrolyzed water treatments, suggesting that electrolyzed water could be used effectively as a pasteurization step for uncooked carrots, cabbage, shiitake and white button mushrooms, sea mustard, and laver.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.245-251
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• 2001

This research was conducted to study the changes in physical characteristics of mushrooms (Agaricus bisporus) as influenced by drying methods. Samples were dried using either hot air drying, vacuum drying, or freeze drying and changes in the color, browning index, hardness and rehydration rate were evaluated by response surface methodology. Hot air drying resulted in the fastest drying of sample as compared to other methods. The rate of drying was most affected by the environmental temperature rather than air velocity or vacuum pressure. The overall color difference increased as the temperature and air velocity increased. The overall color changes of the freeze dried samples were minimal as compared to those of fresh mushrooms. The hot air dried samples showed the greatest changes in the overall color, browning index as well as hardness. The freeze dried samples showed the best rehydration characteristic and maintained the best overall quality after drying.

• Culinary science and hospitality research
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• v.20 no.1
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• pp.55-64
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• 2014

This study was performed to determine the effects of drying methods on the quality and physiological activities of blueberry. Blueberries(Vaccinium ashei) were dried by hot-air ($60^{\circ}C$), cyclic low pressure ($50^{\circ}C$), and freeze drying methods. They contained high properties of carbohydrates(68.48~80.00%), crude protein(1.63~5.41%), crude fat(0.58~1.25%), and ash(0.71~1.11%) regardless of the drying methods. There were no differences in pH according to the drying methods. Browning index increased as the drying temperature increased. The L, a values of the freeze-dried sample were higher than those of the other dried samples, whereas the b value of the cyclic low pressure dried sample was higher than that of the other samples. The free sugar contents of the hot-air sample were higher than those of the other samples. Vitamin C content of the freeze dried sample was higher than that of either the hot-air or cyclic low pressure dried sample. The contents of total polyphenols and anthocyanins were higher in the freeze dried sample. The DPPH radical scavenging activity of freeze drying sample was higher than that of either the hot-air or cyclic low pressure dried sample. The result indicated that there were no differences in product quality depending on the freeze-drying and cyclic low pressure drying methods.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.635-641
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• 2006

In an attempt to find ways of improving the quality and sanitary state of dried squid, this study compared artificial drying methods i.e. hot air drying and cold air drying with natural drying method. The drying rates of squid were in the order of hot air, cold air and natural drying. However, cold-air drying was slower than natural drying at $7^{\circ}C$. The drying rates increased with increasing drying temperature. When drying temperature was close to the dew point on a dehumidifier surface, which was the case with cold air drying at $7^{\circ}C$, the driving force for dehumidification was lower than under other drying conditions, which resulted in a lower drying rate. There were little color differences between the drying methods and temperature. Squid dried by cold air-drying had better mechanical texture and sensory qualities than with other drying methods. In addition, the cold air drying method maintained superior quality in terms of the contents of amino acids, taurine, EPA, DHA, other fatty acids and a low TBA value than the other drying methods.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.278-285
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• 1989

Effects of cooking and drying methods on the taste component and microstructure of shrimp, Metapenaeus joyneri, were investigated. The nucleotides and their related compounds of fresh shirmp such as ATP, ADP, AMP, IMP, inosine and hypoxanthine were detected. AMP was detected as a trace amount in fresh shrimp, however, it increased up to $23.5{\sim}45.7{\mu}$ moles with cooking and drying due to the decomposition of ATP and ADP to AMP during cooking and drying. The major component of the free amino acids of fresh shrimp was arginine followed by glycine, lysine, proline and alanine. These free amino acids contents were 70% of the total free amino acids. One hundred grams of fresh shrimp contained 1,198mg (dry basis) of the total free amino acids. However, for hot air and freeze dried cooked shrimps it was decreased down to 342mg (dry basis) and 503mg (dry basis), respectively. It might be due to the dissolution of soluble amino acids during cooking. Hot air-and freeze-dried fresh shrimps was higher in hardness and brittleness but lower in cohesiveness and gumminess than hot air-and freeze-dried ones with boiling and microwave heating. Freeze dried shrimp had softer myofibril texture than hot air dried one. At the same time, more dense and multiporous structure in the tissue could be obtained from the hot air and freeze drying, respectively, after microwave heating of shrimps.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1582-1588
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• 2011

Caposiphon fulvescens was dried by the hot-air (50$^{\circ}C$), vacuum (50$^{\circ}C$), and freeze drying methods. The green alga contained high proportions of carbohydrates (38.10~41.54%), ash (31.86~33.28%), and crude proteins (17.46~23.03%) regardless of the drying methods used to prepare the sample. The total sugar contents of the hot-air and vacuum dried samples were higher than that of the freeze dried sample (p<0.05). Vitamin C content of the freeze dried sample was higher than that of either the hot-air or vacuum dried samples (p<0.05). The major amino acids were glutamic acid, proline, and aspartic acid, which amounted to 33.34~34.80% of the total amino acid content depending on the drying methods used. Total mineral content of either the hot-air or vacuum dried samples was significantly higher than that of the freeze dried sample (p<0.05). Regardless of the drying methods, Na, K, Mg, Ca, and P were the most abundant elements in the samples while trace elements were identified as Fe, Mn, Zn, and Cu.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.13-18
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• 1978

The present study was conducted to elucidate the pattern in changes of trimethylamine oxide and related compounds in the muscle of Alaska pollack during drying, especially referred to formaladehyde and dimethylamine. Three kinds of dried samples of Alaska pollack, sun dried, hot-air dried, and salted-sun dried, were prepared and analyzed for their contents of trimethylamine oxide, trimethylamine, dimethylamine, and formaldehyde. The amount of trimethylamine oxide remained in the salted-sun dried sample was relatively higher than those in the other two samples. In the content of trimethylamine, the hot-air dried sample showed an exceedingly high value shelving forty-two times higher than the raw sample while the other two samples showed barely three to four times content based on the raw sample. The dimethylamine content in the hot-air fried sample was comparatively lower than those in the other two samples, the former marked about ten folds of the raw sample's and tile latter showed about fifteen folds, respectively. Refering to the content of formaldehyde, it decreased to eighty-three percent of initial content in the hot-air dried sample. On the contrary, it increased about two times initial content in the other two samples, respectively. As a tendency, the formaldehyde content appeared increased or decreased correlatively with the dimethylamine content, whereas the case was reverse for the trimethylamine content.

• The Korean Journal of Food And Nutrition
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• v.12 no.3
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• pp.258-264
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• 1999

This study was carried out to investigate the status in weight loss yield of edible meat quality and free amino acid contents of the snow crab(Chionoectes japonicus) by steaming and various drying treat-ment. Change of body weight loss in steaming treatment sample were 20.48∼26.72% and yield of edible meat of steaming sample was higher than raw sample(p<0.05) The pH value was increased with steam-ing and drying and pH of trunk meat was more increased than leg meat. Volatile basic nitrogen(VBN) content of vacuum dried sample was highest and VBN of hot-air and freezing dried sample were about 10mg%. Content of vaccum dried sample wre 41.33 and 48,56mg%. Thirty kind of free amino acids dectected in the snow crab and changes of free amino acid in leg meat were markedly reduced by vacuum drying and the reducing ratio of leg meat by freeze drying was little. The major free amino acid of leg and trunk meat were 39.94% 46.78% respectively. The formation of flavor free amino acid in freezing dried sample were high but its hot-air aried sample were small.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.176-181
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• 2007

This study aims to evaluate theoretically heat transfer characteristics and heat flux performance in ondol system of dried type is composed of panel of ceramics to improve of thermal conductivity and fin to expand heat. To this end, we analyzed effect of design factors(temperature of hot water, set temperature of room and thermal conductivity of finishing materials) in ondol system of dried type by heat transfer analysis. The main results of this study are summarized as follows; The deviation of heat flux and temperature was reduced by heat expansion from fin decreasing heat loss generated in air layer. The temperature and heat flux in upper finishing materials surface linearly increased according to temperature increment of hot water, but the temperature distribution in upper surface was assessed uneven. The greater heat resistance value of upper finishing materials, the deviation of maximum temperature and minimum temperature was decreased. Also, we suggested a basic design data about ondol system of dried type through an analysis of simulation results on heat transfer characteristics and heat flux performance.