• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1158-1167
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• 2012

During the peeling, cutting, and shredding of wild root vegetables, the surface is exposed to air. This results in a rapid deterioration in quality and an increase in the potential of contamination by microorganisms, both of which reduce the shelf-life of wild root vegetables in retail markets. Thus, in this study, the effects of various washing treatments on the quality of wild root vegetables, including lotus root, burdock root, and bellflower root, were investigated at 10 and $24^{\circ}C$. Lotus root, burdock root and bellflower root were washed with 0.2% acetic acid (AA), 0.2% citric acid (CA), 500 ppm acidified sodium chlorite (ASC), and tap water (TW), which was used as a control, and stored at $10^{\circ}C$ and $24^{\circ}C$. The changes in total plate counts, coliform groups, polyphenol oxidase (PPO) activity, color, pH, and exterior appearance of the samples were then evaluated. The pH and initial microbial contamination levels were reduced when the root vegetables were washed with AA, CA, and ASC. In particular, initial population levels of total plate counts and coliform groups were not detected in lotus root and burdock root that had been washed with ASC and their growth was significantly (p<0.05) inhibited during storage at 10 and $24^{\circ}C$ when compared to the control (TW). In addition, the polyphenol oxidase (PPO) activities of the root vegetables washed with AA, CA and ASC were lower than that of root vegetables washed with TW. ASC was determined to be the most effective treatment for preventing microbial growth, tissue softening, and the development of browning and an unpleasant smell. At $10^{\circ}C$, the overall qualities of the wild root vegetables were maintained longer when compared to $24^{\circ}C$.

• Journal of Nutrition and Health
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• v.3 no.3
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• pp.129-135
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• 1970

From the previous studies, F-P-4 formula was found to be comparable to full fat dry milk in its nutritive value and feeding performance. However, an attempt was made in order to make sure whether or not any possibility might exist, by which further improvement of nutritive quality and simultaneous reduction of product costs may be achieved. Using F-P-4 as a control, modifications were made in new formulas, F-P-5, F-P-6 and F-P-7 by reducing FPC, eliminating yeast from the mixture, and by enriching with methionine as needed. In particular, F-P-7 is completely free of FPC, hydrogenated oil and yeast. Yet, levels of total protein and fat were kept equal to those of F-P-4 in all formulas. An animal feeding test for all formulas using 10 female rats per group for 8 weeks and an infant feeding trial for F-P-5 and F-P-6 with 5 of each female infants under age of one for one month were conducted along with F-P-4 as a control. Almost the same results were obtained with F-P-4, 5 and 6, but F-P-7 showed the lowest body weight gain. FER of F-P-5 and 6 was 0.20 as was with F-P-4, while that of F-P-7 was 0.16. Acceptability to infants was excellent; growth, appearance and biochemical data were normal. As an example F-P-4 packed in 0.04mm polyethylene bags was used for storage study at $25^{\circ}C$ and relative humidity of $65{\sim}85%$ for 8 months. Although viable bacterial counts and vitamin C contents were reduced, peroxide and TBA values were increased gradually during such storage. Since there are also significant changes in color and organoleptic quality, the expected shelf life under the given conditions is considered to be about 2 months and thus further works are needed both on the product and packaging in order to improve the storage stability. Either elimination of yeast form F-P-4, that is F-P-5, or partial replacement of FPC with methionine, that is F-P-6 may well reduce material costs about 10%. Considering blending process of ingredients, F-P-5 is thus found to be the best formula developed. While F-P-7 free of FPC is inferior in its nutritive quality than that of others, but significantly superior than of rice. Furthermore, the material cost of the product can be reduced about 20% from that of F-P-4. And thus this vegetable blend is considered to be useful as a low cost supplementary food mixture for growing children.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.140-145
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• 2017

This study was conducted to find out the effects of $CO_2$ fertilization (1,000ppm) on the quality and storability of 'Maehyang' strawberry fruits. Qualities such as firmness, soluble solid, and acidity of strawberry fruits showed higher numbers in those treated with $CO_2$ fertilization compared to those after harvest. Strawberry fruits were stored at $8^{\circ}C$; MA condition using $20,000cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ OTR (oxygen transmission rate) films and conventional condition using unsealed PE box stored for 20 and 10 days, respectively. Fresh weight loss rate was less than 1.0% in MA storage regardless of $CO_2$ fertilization treatment. Concentrations of oxygen, carbon dioxide, and ethylene in OTR films did not show any significant difference between $CO_2$ fertilization treatment and control (nontreatment) during storage. $CO_2$ fertilization treatments maintained higher firmness after storage regardless of storage methods, but soluble solid, acidity, and surface color did not differ among the treatments. Visual quality and off-flavor based on sensory evaluation was the highest in $CO_2$ fertilization treated strawberry and stored at a MA condition, and was the lowest in $CO_2$ fertilization treated strawberry and those stored in a conventional condition, respectively. The fungal incidence rate of strawberry fruits showed less in $CO_2$ fertilization treatment than control during both MA and conventional storage. These results suggest that $CO_2$ fertilization can improve firmness, increase visual quality after harvest and storage at $8^{\circ}C$, and the MA storage method enhances the shelf-life of 'Maehyang' strawberry fruits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.761-766
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• 2015

This study investigated the effect of protease on quality characteristics of sponge cake. Protease was used at levels of 0.0005 U (PC-1), 0.0010 U (PC-2), 0.0015 U (PC-3), and 0.0020 U (PC-4) for sponge cake preparation. Amylogram showed the setback was significantly decreased in comparison with the control (P<0.05). Height and baking loss rate of control sponge cake were $4.24{\pm}0.18cm$ and $12.01{\pm}0.29%$, respectively. PC-3 and PC-4 showed increased heights of $5.22{\pm}0.16$ and $5.24{\pm}0.11cm$ as well as slightly increased baking loss rates of $12.71{\pm}0.31%$ and $12.89{\pm}0.61%$, respectively. Specific volume and color difference measurements of control showed a specific volume of $3.53{\pm}0.06mL/g$, crust color difference of $53.05{\pm}0.28$, and crumb color difference of $29.84{\pm}0.52$. Measurements of specific volume, crust color, and crumb color of PC-3 and PC-4 were $4.18{\pm}0.02mL/g$, $56.19{\pm}0.84$, $29.05{\pm}0.43$, $4.21{\pm}0.02mL/g$, $56.85{\pm}0.43$, and $29.45{\pm}0.47$, respectively. Firmness measurements showed that the control had the highest firmness. PC-3 and PC-4 were effective at improving the shelf-life of sponge cake as indicated by reduced firmness. Sensory evaluation results demonstrated that all samples scored higher than the control. Throughout the results, the addition of protease increased volume and improved quality characteristics of sponge cake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.752-760
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• 2015

Effects of maltogenic amylase on textural properties of dough and quality characteristics of white pan bread were investigated. White pan bread was prepared with four different levels of maltogenic amylase contents (M-1: 0.048 U/g, M-2: 0.060 U/g, M-3: 0.072 U/g, M-4: 0.084 U/g). The setback by amylograph for the control was $480.0{\pm}12.25$ Brabender Unit (B.U.) while M-4 showed the a setback of $215.0{\pm}5.00B.U.$ The absorption, mixing tolerance index, and stability by farinogram were not significantly different (P>0.05) for across all treatments. The area under the curve (135 min) by extensogram was higher than all samples. The texture profile analysis results showed that there was significant decreasing in hardness for the maltogenic amylase infused bread (P<0.05). M-3 and M-4 showed higher springiness and cohesiveness but lower hardness than control over 1 to 3 days, indicating possibly extended shelf-life. Imaging scan showed that air cell size less than $0.4mm^2$ for the control and M-4 were at rates of 94.90% and 95.70%, respectively. For sensory evaluation, M-3 and M-4 showed higher intensities than the control for taste, flavor, texture, mouthfeel, and moistness quality. These results imply that the quality of white pan bread could be improved by adding maltogenic amylase without the use of chemical additives.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.187-193
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• 2005

This study was carried out to investigate the effect of the bleeding times(30sec., 90sec., 150sec.) at slaughtering process on meat quality and storage properties of broiler. The redness$(a^{\ast}\;value)$ of skin, wing, leg muscle decreased at high bleeding time(150sec.). However, there was no significant difference in breast muscle. WHC(water holding capacity) of breast muscle decreased from $63.64\%$ at low bleeding time(30sec.) to $61.06\%$ at high bleeding time. TBARS(thiobarbituric acid-reactive substance) values were 0.18 mgMA/kg at the low bleeding time, 0.16 mgMA/kg at the middle bleeding time(90sec.) and 0.21mgMA/kg high bleeding time on 3 days of storage. Total aerobic plate counts(TPC) were $6.25logCFU/cm^2$ at the low bleeding time, $6.25logCFU/cm^2$ at the middle bleeding time and $6.53logCFU/cm^2$ at the high bleeding time. The TPC was increased as the bleeding time increased. In conclusion, meat color of chicken were acceptable when the carcasses were slaughtered at the high bleeding time.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.834-844
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• 2014

Postharvest browning of mushroom (Agaricus bisporus) reduces the shelf life of harvested mushrooms. Here, mushrooms were dipped in various solutions (distilled water; DW, 0.25% rice bran extract; RB, 0.1% ascorbic acid; AA, RB + AA) for 3 min. After air-drying at room temperature, the dipped mushrooms were packaged in a polypropylene (PP) films and stored at 4 or $15^{\circ}C$. The quality changes of mushrooms were measured in terms of color, gas composition, firmness, and sensory evaluation during storage. Rice bran extract was measured for total polyphenol content, total flavonoid content, DPPH, ABTS radical scavenging, chelating activity and PPO inhibition activity. No difference in firmness were found in the mushroom samples regardless of dipping solution or storage temperature. At both 4 and $15^{\circ}C$ storage temperatures, RB + AA solution-dipped samples showed the highest L value and lowest delta E value. During the storage period, sensory evaluation showed that overall acceptability of mushrooms treated with RB and RB + AA solution was higher than that of the untreated mushrooms. Total polyphenol and flavonoid contents of 0.25% rice bran extract were $36.42mg\;GAE{\cdot}g^{-1}$ and $4.85mg\;QE{\cdot}g^{-1}$, respectively. The DPPH and ABTS radical scavenging activity of 0.1% ascorbic acid was higher than that of 0.25% rice bran extract. The highest copper ($Cu^{2+}$) chelating activity was found in the 0.25% rice bran extract. The PPO inhibition activity of 0.1% ascorbic acid was higher than that of 0.25% rice bran extract. Our results suggest that 0.25% rice bran extract with 0.1% ascorbic acid is effective anti-browning agent for maintaining quality of Agaricus bisporus during storage.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.324-331
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• 2009

Peeled whole onions (PWO) were cleaned at various hypochlorous acid (HA) concentration and steeping time and packed in LDPE bag keeping at $10^{\circ}C$ for 12 days and $35^{\circ}C$ for 3 days, in order eventually to examine microbiology, surface color and sensory quality. At the early stage of storage, it was found that total bacterial counts at H-II keeping at $10^{\circ}C$ after 1 minute steeping were $2.60\;{\pm}\;0.18\;log\;CFU/g$, and those after 3 minutes steeping were $2.10\;{\pm}\;0.18\;log\;CFU/g$ which showed less than the control. The total bacterial counts at H-III were detected after 4 days. The total bacterial counts of PWO treated HA increased as steeping time became longer, HA concentration increased, and storage temperature went down. E. coli was not detected at all treatments. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b- value showed increasing trend. But these trends were mitigated as HA concentration increased. The result of sensory quality evaluation for the appearance showed that the sample stored with $10^{\circ}C$ gained higher evaluation than that with $10^{\circ}C$, while the control and H-III gained highest points significantly (p < 0.05) for the sample keeping at $10^{\circ}C$ after 12 days storage. The sensory odor of onion showed similar to that for the appearance, and the 8-day treatments of H-II and H-III showed no significantly difference (p < 0.05). On the basis of the results above, it is likely to be more effective to prolong the period of circulation of PWO if you use HA over 50 ppm for washing PWO and storage at $10^{\circ}C$. This study will contribute to improve safety and quality in circulation of PWO.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1079-1085
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• 2003

Modified atmosphere packaging was applied to oyster mushrooms (Pleurotus ostreatus) to study the effect of storage temperatures and packaging materialso. Whole mushrooms (200g) were package with polyethylene film $(PE,\;60{\mu}m\;thickness)$, ethylene vinyl acetate (EVA), or ceramic film (containing 5% zeolite) and stored at 0, 5, 10 and $20^{\circ}C$. Weight loss, color, firmness, gas composition $(O_2,\;CO_2)$ inside the film package and ethanol content in the tissue of MA packaged mushrooms were examined. Mushroom that were packed unwrapped in a conventional hardboard box (2 kg) lost marketability at a very early stage of storage due to weight loss, shrinkage, browning, and spore formation. During storage, film packaging prevented or retarded the deterioration of the mushrooms in the aspects of appearance, texture, and discoloration. Firmness slightly decreased with storage time. Total color difference was much higher in the control than in the film-packaged mushroom and rapidly increased at the early of storage. Correlation analysis showed a high correlation between total color difference and b values. These results were characterized by the reduced respiration rate resulting from elevated carbon dioxide and reduced oxygen levels in the package. At all storage temperatures, ethanol content in the tissue increased slightly at the early part of storage and rose considerably towards the end of the storage period. Ethanol content in the oyster mushrooms was higher in the stipe than in pileus tissues. The shelf life of the oyster mushrooms was about $8{\sim}11$ days at $0^{\circ}C$, about $4{\sim}6$ day at $5^{\circ}C$, about $2{\sim}3$ days at $10^{\circ}C$, and about $1{\sim}2$ days at $20^{\circ}C$.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.387-394
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• 2015

The red snow crab lives at a depth 200-2,000 m in the east coast. It has a smooth taste with a rich texture. However mostly red snow crab are only utilized materials. For seafood development, research is needed on using red snow crab in various products. In this study, quality changes in fried rice prepared with red snow crab meat, red snow crab emulsion sauce and red snow crab effluent were investigated. Physicochemical, microbiological and sensory characteristics were determined during storage at -20, 4 and $25^{\circ}C$ for 5 weeks to assess changes in the quality of the fried rice. The pH and acidity values did not show any significant differences at $-20^{\circ}C$. The VBN and TBA values of fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of fried rice stored at $-20^{\circ}C$ during the same storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period. During storage at $25^{\circ}C$, the overall quality was initially 8.0, but rapidly decreased to 1.0 after 5 weeks. In conclusion, the best storage temperature for both quality and safety was $-20^{\circ}C$. The storage condition for instant rice containing red snow crab affects the quality and we confirmed the applicability of using materials from red snow crab.