• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.446-453
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• 2009

This study was conducted to find condition of improving the quality of peach by using surfacing washing system. The rate of weight loss of A,B groups were showed slower decreasing trend than CT group and the value of soluble solid degree was not different significantly among all groups from the results of stored peach treat with surface washing system of peach in the first experiment. The colory value of surface were increased with increasing storage period in all treatments. Browning pace of A,B groups were slower than control. Emission of carbon dioxide was increased from the results of respiration rate, 6-10 mL/kg/hr $(10^{\circ}C)$ and 32-41 mL/kg/hr $(25^{\circ}C)$. In second experiment with surface washing system of peach, the value of soluble solid was showed with similar value from 10 $Brix^{\circ}$ to 13 $Brix^{\circ}$. The pace of soft rot of EW groups were lower than CT groups from the results of hardness during storage period. The results of colory value was not showed with significant difference in $15^{\circ}C$ and $20^{\circ}C$ storage temperature but changed to browning in EW groups. The moisture contents was from 85% to 90% in all groups. And the count of total microorganism of EW groups were lower than control. Also total coliform of EW groups were negative. In sensory evaluation, washing peach was showed higher value with significant difference in all acceptability.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.575-580
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• 1999

In this study, the quality changes of Hoelen was investigated, which were color differences, browning degrees, total phenolic compounds and electron donating abilities to optimize drying condition using hot air and far infrared drying by changing conditions such as temperatures, air velocities and radiation distances. In color values, ${\Delta}b\;value$ decreased with increasing temperatures, while ${\Delta}L$, ${\Delta}a$ and ${\Delta}E\;value$ increased. The browning degrees showed the similar tendency with the color values. Total phenolic components of Hoelen decreased with increasing drying temperature and air velocity, and decreasing radiation distance. On the other hand, there was no significant difference in the changes of electron donating abilities (EDA) of Hoelen among drying methods and conditions. As a result, the hot air drying was more effective method than the far infrared was.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.761-769
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• 2011

The objective of this study was to investigate the physicochemical properties of Korean traditional soy sauces made with soybeans sown in different producing regions(Hadong, Paju) and in different seeding periods(late-May, mid-June, late-June). The total acidity, salt content, chromaticity, browning, amino nitrogen content and the reducing sugar content of the soy sauce samples were compared. It was found that the total acidity level and the amino nitrogen contents were significantly lower in the soy sauce made with mid-June soybeans, and that these properties increased as the sauce aged. Salt content increased with the aging period regardless of the region of production. The reducing sugar content of Paju soy sauce was the highest in late -June, and for the Hadong region, highest in late-May. The sauce made with Hadong soy beans showed an increase in reducing sugar content positively correlated with the aging period. Reducing sugar content in the samples of Paju soy sauce decreased up to 60 days of aging, but increased after this point. In Paju soy sauce, the brightness(L value) was significantly higher in mid-June, and the Hadong variant it was higher in late -May. The yellowness(b value) at the beginning of the aging process was high in late -June for Hadong soy sauce, but overall it was higher in the mid-June period. The more matured soy sauce samples were darker and showed both higher a and b values. The browning was the lowest in the mid -June regardless of the regions and it increased with the aging period regardless of the production regions. The salt, amino nitrogen contents, browning and yellowness showed significant correlations among the samples. In conclusion, the seeding period of soy beans may affect the characteristics of produced soy sauce alongside the aging conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.83-93
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• 1982

In this work, lipid oxidation and the kinetics of the oxidation reaction in fried file-fish meat were investigated when sun-dried file-fish was stored under the conditions of various water activities and temperature, 35, 45, 55 and $35/55^{\circ}C$. The storage stability and the development of browning by oxidative rancidity were also discussed. Monolayer coverage value of water content in dried file-fish was $8.03\%$ at $0.21\;a_w$Lipid oxidation at $35^{\circ}C$ was developed with increasing water activity but at $45^{\circ}C$and $55^{\circ}C$ it was rapidly progressed without clear differences between water activities except $0.44\;a_w$. The rate of reaction was more sensitive to storage temperature than to water activity. Browning in methanol-chloroform fraction was developed linearly by the progress of lipid oxidation which suggested that lipid oxidation was greatly influential to the development of browning in dried fish meat. In kinetical analysis the oxidation followed a zero order reaction mechanism as a function of carbonyl value. The activation energies obtained from the Arrhenius plot ranged 9.0 to 10.8 Kcal/mol and $Q_10$ values, 1.6-1.7. Shelf-lives at the storage of 35,45 and $55^{\circ}C$ ranged 58 days to 8 days. And in the fluctuating temperature storage at $35/55^{\circ}C$, shelf-lives were 17, 16, 15 and 13 days at 0.44, 0.52, 0.65 and $0.75\;a_w$, respectively. The shelf-lives for assessed from the accelerated shelf-life test were 125, 123, 120 and 106 days at 0.44, 0.52, 0.65 and $0.75\;a_w$, respectively, in the case of storage at $25^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.306-312
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• 2008

This study investigated the influence of pH on the color development of melanoidins formed from amino acid enantiomer model systems. For this, the color development was evaluated by measuring browning at 420 nm and color measurements by spectrophotometry and colorimetry. The browning and browning index showed no difference according to the type of amino acid enantiomers, while that formed from the D-Asn system was the only difference according to pH level. The tristimulus value of melanoidins formed from all model systems was located on a dominant wavelength of 475 nm, the blue zone of the diagram. In addition, the $L^*$, $a^*$, $b^*$, $C^*_{ab}$ values, and ${\Delta}E^*$ index on the basis of the type of amino acid enantiomers, the differences were markedly found at pH 4.0. At pH 7.0, significantly differences were found in the $L^*$, $a^*$, $b^*$ values, and ${\Delta}E^*$ index and not in the case of the lysine enantiomers. In addition, at pH 10.0, the differences were found in the $a^*$ and $b^*$ values from the lysine enantiomers and $C^*_{ab}$ value from the asparagine enantiomers. Therefore, the color development of melanoidins was influenced by the type of amino acid enantiomers and pH levels. Especially, it is thought that the $a^*$ and $b^*$ values can be used to explain the differences among the amino acid enantiomers in the color development of melanoidins.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.361-367
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• 1999

It was reported that green tea extract has antioxidant and antimicrobial activities. To improve the quality of seasoned squid, green tea water extract was sprayed on seasoned squid (water content 25%) and water content was adjusted to 27% and 29%. During storage at $30^{\circ}C$, TBA value, total plate count, browning were analyzed. Browning were analysed by 3 different method (absorbance of water solubilized color, 5% KOH-methanol solubilized color and color difference meter). Water and 5% KOH-methanol solubilized color showed good correlation, but color index detected by color difference meter was not. Green tea water extract slowed TBA value increment and reduced total plate count, so it was supposed that green tea water extract acts positively in manufacturing seasoned squid.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.183-187
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• 2006

Surface browning, caused by cutting and other wound during minimal processing, is very important quality criterion to consumers. Shelf-life of fresh-cut potatoes was extended using natural antibrowning treatments. Fresh-cut potatoes dipped with licorice and green tea extracts were packed with LDPE film and stored at $4^{\circ}C$ for 14 days. Quality characteristics of fresh-cut potatoes were investigated during storage. During storage, L value decreased and PPO activity increased. PPO showed the lowest activity at around 7 days storage, during which browning was effectively inhibited in licorice- and green tea extract-treated potatoes. Total phenol and chlorogenic acid contents increased for 7 days. Results suggest natural licorice extracts with ascorbic acids are effective antibrowning agents for maintaining quality of fresh-cut potatoes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.905-910
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• 2004

This study was carried out to observe the change of oriental melon juice quality during manufacture by heating condition and enzyme treatment. To use over-production oriental melon effectively, oriental melon juice was prepared with change of heating temperature and heating time. The heating conditions for minimum filtration time were 98.57$^{\circ}C$ and 11.29 min. The optimum conditions Predicted for separation ratio of clear solution, filtration time and browning color intensity of oriental melon juice were 98$^{\circ}C$, 13 min. In the pectin-degrading enzyme treatment test, turbidity showed minimum value in 4.40 mg％(pectin-degrading enzyme content)， 39.72 mg％ (gelatin content) and 24.09 min (treatment time)．Browning color intensity showed minimum value in 9.33 mg％ (pectin-degrading enzyme content)，44.70 mg％ (gelatin content) and 115.56 min (treatment time). The optimum conditions predicted for turbidity and browning color intensity of oriental melon concentration Juice were 6.6 mg％ (pectin-degrading enzyme content), 33.6 mg％ (gelatin content) and 70 min (treatment time).

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.382-386
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• 1997

In the present study, an attempt was made to investigate the effects of steeping treatment on browning of onion hydrolysate. After steeping treatment with solvents, phenols content of methanol and ethanol were showed 25.1mg/ml and 24.9mg/ml. And absorbance of methanol and ethanol was showed 0.26 and 0.22. L and b value of treatment with methanol and ethanol were lower than other solvents. Browning reaction of onion hydrolysate was decreased with increasing concentration of ethanol. Treatment of above 80% ethanol was effective to remove phenols and was showed a low color intensity. Treatment with 80% ethanol was more effective than addition of cystein to remove phenols and to decrease browing degree.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.509-513
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• 1990

Browning and color characteristics of stored mushrooms (Agaricus bisporus)following ionizing irradiation were investigated in connection with quality deterioration. The phenolic compounds of stored mushrooms showed a gradual decreasing tendency, while extractable browning pigments apparently rose from around 3days of storage under the conditions of $9{\pm}1^{\circ}C,\;80{\pm}7%$ RH and packaging with a corrugated paper box wrapped up in PE. ${\gamma}-irradiation$ at 2 to 3 kGy resulted in a significant reduction of their changes. Immediately after treatment, irradiated mushrooms were more discolored, i.e. a lower Hunter L value and higher Hunter a and b values than control. However, the subsequent storage for 15 days resulted in a preventive influence of ionizing energy on mushroom discoloration. This beneficial effect of ionizing energy was somewhat higher in the pilei than in the stipes of mushrooms and was found to increase lineally with increasing doses up to 3 kGy.