• Culinary science and hospitality research
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• v.20 no.6
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• pp.235-244
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• 2014

The purpose of this study was to investigate the effect of freezing and thawing rate on the physical properties of soybean sprouts to improve the quality of processed soybean sprouts during distribution and storage. Cooked soybean sprouts were frozen by air-blast freezing (ABF) system at $-45^{\circ}C$ or natural air convection freezing (NCF) system at $-24^{\circ}C$, then thawed using microwave oven by varying output power (0, 400, 800 and 1,000 W) until $75^{\circ}C$. The quality of soybean sprouts was measured by the water content, hardness and springiness. In addition, the internal microstructure of soybean sprouts was observed by optical microscope. For results, water content of soybean sprouts thawed by 1,000 W in a microwave showed the lowest value after natural air convection freezing. Springiness of soybean sprouts thawed by all amounts of output power was decreased in comparison with control. Hardness was increased only in soybean sprouts thawed by 1,000 W after air-blast freezing. However the gaps between springiness and hardness were relatively small with control at 1,000 W thawing, after air-blast freezing. Internal microstructure of the soybean sprouts was more damaged as freezing and thawing time were increased. In conclusion, high freezing and thawing rate might improves the quality of soy bean sprout, and IQF freezing and 1,000 W of microwave thawing appears to be the optimum condition for frozen HMR production. From the results freezing and thawing process parameters might can be use as quality control parameters as various type of sprout products processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1638-1648
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• 2013

To promote the utilization of wild edible plants, this study examined blanching, drying, and fermentation as methods for enhancing the functionality of Hemerocallis coreana Nakai. Specimens fermented for 24 hours at a fermentation temperature of $50^{\circ}C$, with a relative humidity of 65%, contained the highest amount of organic acid (18,109.82 mg/100 g). For the blanched; specimens, total organic acid content decreased about 30% compared with the freeze-dried specimens. The main organic acid of Hemerocallis coreana Nakai was confirmed as succinic acid. After fermentation, free sugars decreased; in particular, specimens fermented at a relative humidity of 80% showed a 32~75% reduction in free sugar compared with the freeze-dried specimens. In terms of amino acid content, Hemerocallis coreana Nakai was mainly composed of valine, isoleucine, and phenylalanine. In fermented specimens the total amino acid content was highest in a moderately fermented (17 hr) specimen, (1,010.71 mg/100 g fresh wt.), but decreased in the maximally fermented (24 hr) specimen. The longer the fermentation, the higher the decrease in non-essential amino acids content, while the content of more essential amino acids consistently increased. In conclusion, since seasoned Hemerocallis coreana Nakai contains a considerable amount of glutamine and asparagine, it has a fresh sour and sweet taste; thus, it will likely be a highly preferred wild edible plant. Also, with an increase of essential amino acids after fermentation, Hemerocallis coreana Nakai is excellent in terms of nutrition. Thus, it may be possible to utilize fermented Hemerocallis coreana Nakai in the development of diverse products.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.402-411
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• 2014

This study investigated the quality characteristics of tea leaf pickle with different pickling solutions. Blanched tea leaf at $100^{\circ}C$ for 3 min was pickled using pickling solutions (mixture of water, soy sauce, sugar and vinegar) with different vinegar contents (10, 20, 30 and 40%, v/v). and stored for 30 days at $4^{\circ}C$. The color values, hardness, pH, total acidity, sensory evaluation, antioxidant compound contents, DPPH radical scavenging and ABTS radical scavenging of the pickled tea leaf during storage were determined. The pH of tea leaf pickles decreased consistently and total acidity was increased during storage. The L-value of tea leaf pickles was decreased and the a-value was increased significantly during storage; however, the b-value had no significant changes (p<0.05). The hardness of the tea leaf pickles decreased consistently during storage. On the sensory evaluation, the highest score of overall acceptance was presented to the tea leaf pickle using a 20% vinegar pickling solution stored for 20 days. The antioxidant compound contents and antioxidant activity consistently decreased during storage; further, the experimental group of vinegar with 20% content tea leaf pickle displayed the lowest antioxidant compound content and antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.207-215
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• 2014

To investigate the biological benefits of Korean traditional vegetables, anti-oxidative and anti-inflammatory effects of ethanol extracts from blanched and dried sprouts of evening primrose (Oenothera laciniata, OL) and gooseberry (Actinidia arguta, AA) were measured. Total polyphenol and flavonoid contents of OL were higher than those of AA; OL contained 60.4 mg tannic acid/g dry weight and 31.9 mg rutin/g dry weight, while AA contained 33.0 mg tannic acid/g dry weight and 20.3 mg rutin/g dry weight. The $IC_{50}$ value for DPPH radical scavenging activity was $58.2{\mu}g/mL$ for OL ethanol extract and $122.1{\mu}g/mL$ for AA ethanol extract. The reducing power upon $500{\mu}g/mL$ of ethanol extract treatment was as strong as $52.1{\mu}g$ ascorbate eq./mL for OL and $45.3{\mu}g$ ascorbate eq./mL for AA. Regarding anti-inflammatory effects, inhibition rate against 5-lipoxygenase (LOX) and cyclooxygenase (COX)-2 activities were 29.5% and 79.5% for OL, as well as 11.5% and 39.1% for AA, respectively at a concentration of $250{\mu}g/mL$. Lipopolysaccaride ($1{\mu}g/mL$)-treated RAW 264.7 macrophage cells subjected to OL ethanol extract at various concentrations ($0{\sim}25{\mu}g/mL$) showed significantly reduced synthesis of nitrite oxide (NO), prostaglandin (PG) E2, and IL-6 in a dose-dependent manner without cytotoxicity, although TNF-${\alpha}$ synthesis was not affected. In conclusion, both OL and AA sprouts showed strong antioxidative activity, whereas OL showed very strong anti-inflammatory activity via effective reduction of NO, PGE2, and IL-6 synthesis in LPS-activated macrophage cells.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.250-257
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• 2016

This study was conducted to extract the factors affecting the microbial safety of leaf and stem vegetables in the high school foodservice and to provide information for supplying the safe foodservice menu. The lunch and dinner menu (1,945 data) of the total 6 high schools at the Central and the South Region in March, June, September, and December were collected. The frequency analysis and the multiple correspondence analysis (MCA) based on the 3 factors (potentially hazardous food (PHF), leafy and stem vegetables in the menu, the cooking methods) were conducted. The most frequent PHF was the menu of blanched vegetables, salads, seaweeds and fried chicken. The most frequent consumed leaf and stem vegetables were spinach, chive, lettuce, Western cabbage, perilla leaf, iceberg lettuce, chicory, leek and broccoli. MCA based on the leaf and stem vegetables, the region, and the cooking method (cooked/non-cooked) showed that garlic stem and spinach were more used in the Central Region, while water drop-wort were more used in the South Region. Iceberg lettuce, Bok choy and leek were included frequently in the PHF menu. Plant products frequently used in PHF menu requires the food safety system such as Good Agricultural Practice (GAP) to reduce the microbial risk. The menu database according to raw materials based on cooking methods (heating or mixing) as well as the development and verification of menu based on the microbial safety will be contributed to provide the safer foodservice menu.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.43-57
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• 1977

In order to establish methods of potato processing for mixed cooking with rice as main diet, treatment for polyphenol oxidase inactivation in potato tissues, and safety in regard to sanitation were studied. The results were summarized as follows: 1. Cut potato granule which were blanched in boiling water are practical and best in color within $3{\sim}6\;minutes$ dipping. 2. Dipping treatment of potato granules in a saline solution is not pratical because of the resulting color and saline taste. 3. Dipping treatment of potato granules in a boiling saline solution is not practical because of residual salt. 4. Dipping treatment of potato granules in low concentration of hydrochloric acid solution is not effective in color changes but dipping treatment from 0.1N concentration for 4-10 minutes to 0.5N concentration for $1{\sim}10minutes$ shows good effects. 5. Dipping treatment in boiling hydrochloric acid solution of 0.04-0.068N concentration for 3-5 minutes dipping is practical for its resulting color. 6. Dipping treatments in 0.05% of $K_2S_20_5$ solution for $50{\sim}60\;minutes$ and in 0.06% for $40{\sim}60\;minutes$ and 0.065% for $10{\sim}60\;minutes$ shows a small palatability in color but its boiled potato granules shows good color 7. Treatments for any time in $0.01{\sim}0.03%$ of boiling $K_2K_20_5$ solution after predipping in its cold solution for longer time than 30minutes show effective in the color and palatability of the potato granules and their cooked ones. 8. From the view of food sanitation, dipping treatment of the potato granules in the solution of $K_2S_20_5$ is safe because of the few residual amount of $SO_2$. 9. All the methods of treatment that potato granules are dipped for any time at 0.01% of $K_2S_20_5$ solution are safe from the view of fond sanitation. At 0.03% of $K_2S_20_5$ solution, nothing but the methods of treatment that they are dipped within 30 minutes and boiled within 4 minutes are safe.

• Food Science and Preservation
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• v.18 no.5
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• pp.661-668
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• 2011

This study was conducted to devise appropriate blanching-process conditions as a means to convert Doraji, which is widely used in Korean food due to its unique fragrance and flavor, into frozen food materials for various uses. For the Hunter L values representing the brightness transformation among the surface color and gloss changes that were observed in Doraji before and after freezing, and after Doraji went through a blanching process, the specimen that went through a blanching process at $80^{\circ}C$ showed a significantly higher value compared to another specimen processed at a higher temperature, and the first specimen's value also rose after freezing. Meanwhile, for the hardness values, they declined more as the blanching temperature became higher and as the processing time became longer. For the number of total counts and the number of coliform groups, the number of total counts at $3.75{\times}10^5$ and $1.25{\times}10^5$ cfu/g before the blanching process was reduced into the approximately 2-3 log scale, and no coliform group was detected after the blanching process. As for the peroxidase activity, its activation was decreased by the blanching process, and more than 89% of the peroxidase became inactivated in all the specimens that went through the blanching process. The sensory characteristics of the frozen-thawed Doraji by test group showed the radish leaves blanched at $90^{\circ}C$ for 1 min to be the most highly evaluated in terms of the overall preference level (p<0.05).

• Food Science and Preservation
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• v.11 no.2
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• pp.195-200
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• 2004

Microbial lethal value and nutrient retention of sous vide processed spinach were evaluated with mathematical model prediction and experimental trial for different package sizes and pasteurization temperatures. The package size covers 500 g, 1 kg and 2 kg, while the pasteurization temperature includes 80, 90 and 97$^{\circ}C$. The basic process scheme consists of filling blanched spinach into barrier plastic film pouch, sealing under vacuum, pasteurization in hot water with over pressure and final cooling to 3$^{\circ}C$. Pasteurization condition was designed based on attainment of 6 decimal inactivation of Listeria monocytogenes at geometric center of the pouch package by heating cycle, which was determined by general method. Heat penetration property of the package and thermal destruction kinetics were combined to estimate the retention of ascorbic acid and chlorophyll. Smaller packages with shorter pasteurization time gave better nutrient retention, physical and chemical qualities. Larger package size was estimated and confirmed experimentally to give higher pasteurization value at center, lower ascorbic acid and chlorophyll contents caused by longer heat process time. Lower pasteurization temperature with longer process time was predicted to give lower pasteurization value at center and lower ascorbic acid, while chlorophyll content was affected little by the temperature. Experimental trial showed better retention of ascorbic acid and chlorophyll for smaller package and higher pasteurization temperature with shorter heating time. The beneficial effect of smaller package and higher pasteurization temperature was also observed in texture, color retention and drip production.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.382-388
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• 1994

Because of its restrictive harvest from spring to summer, It is necessary to preserve raw ascidians, Halocynthia roretzi, for the purpose of processing regardless of season. We evaluated low Temperature tolerance of ascidian and conditions for cold storage to secure the quality of the stock. To retard the browning of meat rapidly occurred after sucking, ascidians were blanched for 10 seconds in 10% boiling salt solution or dipped for 60 seconds in 0.2% $NaHSO_3$ solution, respectively. The samples were stored in ice, at $-17^{\circ}C$ or $-35^{\circ}C$ for 85 days, respectively. Changes in VBN, glycogen, brown pigment formation, total carotenoid, nucleotides and their related compounds during the storage were determined, and sensory evaluation of quality was also practiced. VBN and brown pigment formation were rapidly increased. Glycogen was gradually decreased and then not detectable after 85 days in case of ice storage. Lipophilic brown pigment was higher than hydrophilic and rapidly increased during storage. The result of sensory evaluation showed that the ascidian treated in 0.2% $NaHSO_3$ was good for 85 days of storage at $-35^{\circ}C$ . Judging from the results of chemical experiment and sensory evaluation, the quality of ascidian treated in 0.2% $NaHSO_3$ and stored at $-35^{\circ}C$ was better than that of other samples.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.242-251
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• 1989

The salted-dried mullet(Mugil japonicus) roe is a kind of traditional food particulary in the area of Young-am gun, Chunnam province. This study was conducted to conform the scientific processing conditions and to evaluate the nutritional quality and changes of major components during storage times. The manufacturing method was that the fresh roe was salted for about 20 hours for the preparation of salted-dried roe, washed by clean waters, drained, shaped a flat piece with 1.2cm thickness by pressing, and spreaded sesame oils on the surface of the salted roe periodically during wind drying for 20 days. The dried roe was blanched in heated water$(80^{\circ}C/3min)$ and packaged the dried product for storages. The fractional compositions of free lipid of wind dried roe were 40% of neutral lipids, 12% of glycolipids and 9% of phospholipids and those of bound lipids were 13% of neutral lipids. 10% of glycolipids and 13% of phospholipids respectively. The major fatty acids of the roe were $C_{16:0}$, $C_{18:0}$, $C_{18:1}$, $C_{18:2}$ and $C_{20:0}$ which was consisted of free and bound lipids in wind drying method during processing and storages. Total amino acids were 99.87g/100g and major amino acids were Glu, Pro, Leu, Lys and CySH and the protein score was average 155% and the chemical score was average 109%. Free amino acids was 1,376mg% that had 50.61% of Pro and the major kinds of those were Tyr and CySH.