• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.150-155
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• 1997

The twenty strains of Lactobacillus genus were tested for the optimal sponge fermentation of soda cracker. The six strains such as L. brevis, L. delbrueckii, L. fermentum, L. leichmanii, L. plantarum and L. sanfrancisco were selected because these strains did not smell off-flavor and showed the high value of TTA (total titrable acidity) after the fermentation. The selected strains consisted of the five strains of L. brevis, L. delbrueckii, L. fermentum, L. leichmanii and L. plantarum that mainly inhabited soda clacker and L. sanfrancisco that existed in San Francisco bread. The lactic acid bacteria were inoculated to the medium containing 10% wheat flour and then pH, TTA, acetic acid and lactic acid were measured during the sponge fermentation. The four strains of L. brevis, L. delbrueckii, L. fermentum and L. plantarum were used for the mixed lactic acid bacteria of sponge fermentation because the TTAs of L. brevis, L. fermentum and L. plantarum were higher than those of other lactic acid bacteria and L. delbrueckii rapidly produced organic acids and a large amount of acetic acid. Among the combination of L. brevis, L. fermentum, L. delbrueckii and L. plantarum, the mixed lactic acid bacteria of L. brevis, L. fermentum and L. plantarum showed the highest TTA, the lowest pH and the largest amount of acetic acid. Therefore, the mixed lactic acid bacteria of L. brevis, L. fermentum and L. plantarum were used for optimal sponge fermentation of soda cracker.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.425-430
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• 2005

Relative sweetness of sucralose, an intensive sweetener, to sucrose or fructose in binary model solution and beverage systems was examined. Sensory properties of sucralose solution, orange flavored beverage and sports drink containing sucralose were evaluated at the equi-sweetness to sucrose or fructose. Consumer acceptability tests were performed on orange flavored beverage. Relative sweetness of sucralose to sucrose was 350 and 500 in binary model solution and orange flavored beverage, respectively, while that of sucralose to fructose in sports drink was 550. All the sensory properties, except astringency, of sucralose solution examined were similar to those of sucrose solution. The sensory properties of orange flavored beverage, in which 50% sucrose was replaced with sucralose, were very close, and showed comparable or higher overall acceptability to that containing sucrose only. When fructose was replaced with sucralose in sports drink sour, salty and bitter tastes, metallic flavor, and astringency slightly increased.

• Food Science and Preservation
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• v.15 no.6
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• pp.810-815
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• 2008

Improving quality is a very important component of maintaining competitiveness of agricultural products. However, evaluation of 'high quality' indicates it is a very abstract concept and independent of some quality attributes, leading to differences in the perception of quality. Thus, there is a pressing need to objectively define 'high quality' and to develop basic technologies for its measurement, for application in the production, storage and distribution of competitive agricultural products. To objectively quantify apple quality, a survey was conducted on consumer preferences and awareness of quality attributes including color, taste, flavor and shape. The survey questionnaire targeted male and female adults (463 persons) ranging in age from 20 to 59 years. The questionnaire was based on purchases made at a wholesale market (50.1%) or a traditional market (18.8%). The majority of purchases were as small packets (62.0%) or as individual pieces (20.5%). Apples of moderate size (fist size, 60.5%) were preferred over small (4.3%) or large (32.6%) apples. The questionnaire provided consumer data on external quality attributes including color, shape and variety. Taste attributes were evaluated in relation to the balance between sour and sweet taste, and flavors peculiar to apples.

• Food Science and Preservation
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• v.17 no.4
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• pp.457-465
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• 2010

We sought to develop lotus (Nelumbo nucifera) root Jeonggwa as a health food. Jeonggwa was mixed with 0-8% (w/w) Omija water extract and stored at $25^{\circ}C$ for 12 weeks. Quality characteristics during storage were investigated. The pH of Jeonggwa fell, and the acidity level rose, as increasing amounts of Omija water extract were added. The moisture content of Jeonggwa rose from 7-8% to 14-17% within 2 weeks of storage at $25^{\circ}C$, and was maintained at that level to the end of storage. Total viable bacterial cells in Jeonggwa were initially 2.4~3.2 log CFU/g, and increased in number during storage, but never exceeded 4 log CFU/g. The shelf life of Jeonggwa was extended when Omija extract was added. The lightness (L), redness (a). and yellowness (b) of Jeonggwa during storage at $25^{\circ}C$ were highest in control samples and the values fell with increasing Omija extract concentration (p<0.001). Mechanical evaluation Jeonggwa showed that various tested parameters fell during storage at $25^{\circ}C$. The hardness and strength of Jeonggwa were significantly reduced as the Omija extract concentration rose (p<0.05). In sensory evaluation tests, the acceptability of Jeonggwa was optimal when 2~4% (w/w) Omija extract was added.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2234-2243
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• 2013

The purpose of this study was to measure using a six-step solution for taste recognition threshold and using a Wet-Test for salivary flow amount of the adults who reside in Daegu area and are more than their 40's old to find out the relationship between DMFT index and OHIP-14. The study result revealed that the practice of oral health gave an effect to taste recognition threshold, dietary habit gave an effect to salivary flow amount, and sweet and sour taste of taste recognition threshold and salivary flow amount gave effects to the DMFT index. Therefore, it was found that the person with good practice of oral health and dietary habit had good taste, salivary flow amount and DMFT index. According to this result, it is necessary to increase the practice of oral health, increase the sensitivity to taste recognition threshold, improve dietary habit, increase salivary flow amount and decrease DMFT index in order to improve OHIP-14. Dietary habit education has been performed without the evaluation on the individual's level of taste recognition threshold. Therefore, it is necessary to develop the education program to measure and notify the taste recognition threshold in the oral health education so that individual can adjust it by himself.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.283-288
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• 2003

The quality and sensory characteristics of kimchi added various levels of rosemary leaf during fermentation at 15$^{\circ}C$ were evaluated. Rosemary leaf amounts were added 0.5g(R0.5%), 1g(R1%), 1.5g(R1.5%) per brined chinese cabbage 100g. The pHs and reducing sugar contents of all experimental groups decreased with increasing the fermentation time, whereas levels of titratible acidity increased. The pHs and reducing sugar contents of experimental groups added rosemary leaf showed higher than control, but titratible acidity of these groups showed lower. Also, the period reached the maximum levels of the log number of lactic acid bacteria counts(cfu/ml) and total viable bacteria counts(cfu/ml) of experimental groups added rosemary leaf were more delayed than control. These results showed that the fermentation of experimental groups added various levels of rosemary leaf were slower than that of control. On the 5th day of fermentation which had most delicious kimchi flavor, the sensory evaluation analyzed by ANOVA followed Duncan's multiple range test showed that sour smell of experimental groups added rosemary leaf was significantly lower, but green flavor and green smell of these groups were significantly higher than control(p<0.05). The most preference among experimental groups was R0.5% and next was control, R1.5%, R1%.

• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.34-39
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• 2017

Typical flow regime of overflow at barrier or weir constructed in mid and small streams becomes as the submerged flow during most flood events. One of major causes of barrier failure has been reported as the levee-scour near the conjuction node between barrier and levee. However, most related design guidelines in Korea have not mentioned about the protection of levee around barrier or weir in detail. Furthermore, most previous researches have focused on the flow characteristics of overflow around several types of weirs but they did not have considered the material properties of levee itself. In this study, local scour near barrier was investigated with different material properties of levee under the submerged overflow condition which is assumed to reenact a flood event. Based on results from Fritz et al. and Mavis et al., a theoretical formula was also proposed in initial stage of laboratory experiments. And hydraulic experiments were carried out for the verification of the proposed formula. Levee was installed in the prismetic trapezoidal open channel and most parts were made of concrete except for movable section in which scour was expected to occur for the efficiency of experimental procedure. Each compaction of movable section in levee was followed by the basis of the KS F 2312. Further, after performing the experiments to find the optimum water content for each sediment, the specific amount of water was injected before flowing water. The difference between the proposed theoretical formula and experiment results was not much but considerable, which might be caused by the effect of compaction. For theoretical approach, it seemed that the formula did not take into account the compaction of levee, thus the correction coefficient for levee compaction determined in the literature was considered. Finally, the formula for the length of scour around barrier or weir was proposed, which can be useful to predict a levee in the reference design of revetment in mid and small streams. As shortly future study, scour length of levee around barrier or weir under different flow conditions such as perfect overflow condition will be studied and it will be able to contribute to suggest the design formula or criteria under all overflow conditions near barrier or weir.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.1-5
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• 1991

This study was conducted to examine the effect of the addition of calcium acetate and/or potassium sorbate on the characteristics of kakdugi(Korean seasoned pickles of cubed radish roots) fermented at $20^{\circ}C$ for 4 days or more. The sensory characteristics, pH, titratable acidity, non-volatile organic acids and texture by Instron were measured. The results of sensory evaluation on kakdugi stored at $20^{\circ}C$ for 4 days indicated that firmness, toughness, crispness, sour taste and overall desirability were increased by the addition of calcium acetate. Potassium sorbate was evaluated to decrease the sourness. Titratable acidity, pH and the amount of non-volatile organic acids were higher in samples containing calcium acetate than in other ones. Compression test with Instron gave the similiar result to sensory evaluation in the measurement of firmness. Calcium acetate and potassium sorbate showed synergistic effect greatly on the textural characteristics on kakdugis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.8-15
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• 1997

For an effective use of fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures, the changes of chemical properties of skipjark tuna viscera silage by the processing method during storage were investigated. The acid treated skipjack tuna viscera silage (ASS) were higher in the contents of moisture, lipid, protein and mineral but lower in the contents of carbohydrate and polyunsaturated fatty acids than those of fermented skipjack tuna viscera silage (FSS) by L. bulgaricus, KCTC 3188 and L. plantarum, KCTC 1048. Especially, the contents of total n-3 fatty acids in FSS increased remarkably during storage. The dominant amino acids in ASS and FSS were glutamic acid (Glu), aspartic acid (Asp), leucine (Leu), glycine (Gly) and alanine (Ala). And the contents of tryptophan (Trp) decreased by $30\%$ in ASS and $5\%$ in FSS in comparision with that of raw skipjack tuna viscera after 42 days of storage. The concentration of vitamin $B_1\;and\;B_2$ in FSS increased gradually during storage but the concentration of vitamin $B_2$ in ASS decreased. In the organoleptic evaluation, ASS gave a grayish brown color and a fishy odor. On the other hand, FSS had reddish brown color and sour taste by the production of lactic arid during storage.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.153-160
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• 2011

In this study, we have developed taste and other functional enhancements of yam chips, from tasteless and flavorless yam slices, through the process of soaking freeze-dried yam in different commercially available juices, including apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng, and black garlic juice. The analyses of color (brightness, redness and yellowness), pH, brix, acidity, total polyphenol, total flavonoids, total sugar and reducing sugar, DPPH and ABTS scavenging activity, reducing power and nitrite scavenging activity, of the different yam chips showed that the freeze-dried yam slices absorb various components of fruit juices, such as flavonoids, sugars, organic acids and flavors, during the soaking process. These changes resulted in increased taste (both sweet and sour tastes), flavor and antioxidant activity in the yam chips. The soaking time for yam slices in juice is considered to be a crucial factor for the taste and bioactivity of yam chips. In the case of grape juice-yam chips, which had the highest preference among the 8 different chips, the optimum soaking time was noted as 120 seconds. The optimization of the soaking process is necessary for various juices. These results suggest that taste, and other functional enhancements, in yam chips can be developed by juice-soaking and freeze-drying methods.