• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.539-542
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• 1990

The effects of immersion temperature $(20,\;40\;and\;60^{\circ}C)$ and immersion times (6. 12 and 18 min) in a distilled water prior to air dehydration upon the browning reaction and pyruvic acid content of air dried onions to a 4.071 moisture content (wet basis) were analyzed by a response surface methodology (RSM). Those values were also predicted by using a second degree polynomial regression model. Immersion temperature had more influence to browning reaction and pyruvic acid content than immersion time in these experimental ranges. The processing conditions to minimize the browning reaction of dried onions at $50^{\circ}C$ of air temperature (O.D.=0.071) were $60^{\circ}C$ of immersion temperature and 18 min of immersion time compared to control (O.D.=0.168) of air dehydration at $50^{\circ}C$ Pyruvic acid contents of dried onions at $50^{\circ}C$ of air temperature were maximized $(39.85{\mu}mole/g\;onion\;solid)$ at $60^{\circ}C$ of immersion temperature and 12 min of immersion time compared to control $(24.08{\mu}mole/g\;onion\;solid)$ of air dehydration at $50^{\circ}C$.

• Food Science and Preservation
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• v.21 no.3
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• pp.357-364
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• 2014

The quality improvement of the boiled-dried anchovy treated with acidic electrolyzed water (AEW) was investigated. The L value was higher in the anchovy treated with AEW than in the control. Moreover, its ${\Delta}E$ value was 5.08 higher than that of the control. The lipophilic browning degree was also higher than the hydrophilic degree. The degrees of calcium absorption of the control and anchovy treated with AEW were 10.77% and 12.61%, respectively. During their storage in the different conditions (five weeks in $20^{\circ}C$, ten weeks in $4^{\circ}C$, and five months in $-20^{\circ}C$), the lipophilic browning degree of the anchovy treated with AEW was significantly lower than that of the control at the $20^{\circ}C$ storage. The volatile basic nitrogen (VBN) content gradually increased as the storage period increased. During the $20^{\circ}C$ storage, the content of the anchovy treated with AEW was lower than that of the control. The lipid peroxide contents increased with the storage periods, regardless of the temperature, but the content of the anchovy treated with AEW was lower than that of the control. These results indicate that AEW treatment can improve the color quality of boiled-dried anchovy and reduce its VBN and lipid peroxide contents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.607-611
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• 1999

Carrageenan are sulfated polymers containing galactose and anhydrogalctose units, and is used for its gelling, thickening, stabilizing, emulsifying, and suspending properties. However, carrageenan is limited to use beyond $0.03\%$ as food additives because of its high degree of gelling and viscosity with low solubility. The use of ultrasound significantly reduced the viscosity of $\lambda$-carrageenan solutions. The optimal parameters of ultrasound for reduction of carrageenan molecular weight were temperature, $10^{\circ}C$ ultrasound intensity, 114.7 $W/cm^2$ ; carrageenan concentration, $2\%$; treatment time, 10 min. The molecular weights of control, ultrasound peak 1, and peak 2 were approximately 250,000, 184,000, and 67,000 daltons, respectively. The lower molecular weight of $\lambda$-carrageenan showed the higher solubility, the lower alcohol precipitation ratio and the lower emulsifying capacity. Browning degree of both control and lower molecular $\lambda$-carrageenans was not significantly different.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.610-617
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• 2019

The effects of dippin treatments using Glycyrrhiza uralensis extract (0.5%, 1.0%, 2.0%) and calcium chloride (0.5%, 1.0%, 2.0%) on the quality of peeled chestnuts were investigated. Following dipping treatment, peeled chestnuts were vacuum-packed using a 75-㎛ polyethylene PE and nylon film, and stored in a 0 ℃ incubator for six weeks. The dipping treatments of the peeled chestnuts successfully achieved browning inhibition. The browning degree following 2.0% calcium chloride treatment was the lowest at 0.68 OD. The color change (ΔE) of the peeled chestnuts was the highest (6.0) in the control, and the lowest (3.5) for the 1.0% and 2.0% calcium chloride-treated samples. G. uralensis extract and calcium chloride treatments did not impact weight, moisture loss rate, firmness, or the soluble solid content of the peeled chestnuts following storage. The decay rate was 12.0% in the control group, and 11.0%, 11.5%, and 11.0% for G. uralensis treatment at 0.5%, 1.0%, and 2.0% calcium chloride treatment, respectively, and 13.0%, 9.5%, and 9.0% at 0.5%, 1.0%, and 2.0% calcium chloride treatment, respectively. Sensory evaluation (palatability, off-odor) showed that a 2.0% G. uralensis extract treatment presented excellent results during the storage period. Texture and color indicated no differences as a result of the browning inhibition treatments. Therefore, when considered comprehensively, a 2.0% G. uralensis extract treatment was shown to be effective for maintaining the quality and providing browning inhibition of peeled chestnuts. This result isexpected to solve the problem of quality deterioration in the form of sour taste, which is a problem in chemical processing.

• Culinary science and hospitality research
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• v.3
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• pp.239-257
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• 1997

This study investigated the effect of the addition of alcohol on the quality change of Chungkukjang during the aging, The Cung-kuk-jang was made by the degree of 3, 5, 10%, respectively, and determined NH2-N, NH3-N, total acidity, cell numbers, lactate, succinate and phenolic acid to measure the change of flavor component in the aging of 2$0^{\circ}C$. 1. In the treatment groups of different amount of alcohol and salt added and aging period of Chung-kuk-hang, NH2-N was more decreased with more addition of alcohol and salt in the 3-and 10-day of aging. NH3-N was increased gradually in the addition of up to 2.0% alcohol and then decreased in the 3-and 10-day of aging. 2. In the treatment groups of different amount of alcohol added and aging period Chung-kuk-hang, the total acidity was more decreased with more addition of alcohol and higher degree of salt. Cell number was decreased rapidly with the addition of 1.0% alcohol in the 3-day and then decreased relatively and in the 10-day of aging, and it was increased with the addition of alcohol 3. With the addition of alcohol and the different growing temperature, the content of phenolic acid was more browning changed at 3$0^{\circ}C$ than that of at 2$0^{\circ}C$ and the phenol content of each group was decreased with increasing the addition amount of alcohol. Thus, the more addition of alcohol amount would the more extend the period of Chung-kuk-hang aging.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.704-710
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• 1988

This study was, firstly, to investigate water holding capacity in terms of variation of moisture sorption isotherms of seasoned squid treated with sodium lactate, glycerol, propylene glycol, sorbitol, mannitol, sodium benzoate, potassium sorbate and calcium propionate, and secondly, the effect of humectant treatments on storage stability was studied. The criteria for storage stability was based on three quality factors, namely, lipid oxiations, color development by non-enzymatic browning reactions and lipid oxidation, and mold growth. The effect of humectants on equilibrium moisture content was in the following increasing order; mannitol < sorbitol < sodium lactate < propylene glycol < glycerol. The experimental data indicated that sodium lactate has, in practice, potentially positive effect on processing of seasoned squid. During the storage period of 60 days, TBA values increased in all samples tested as humectants concentrations increased up to 10%. However, in the range of 1-7% sodium lactate treatment, the degree of lipid oxidation, browning reactions and mild growth were not high enough to affect the quality of seasoned squid, when compared with conventionally manufactured ones.

• 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.35 no.3
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• pp.455-460
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• 2003

Effects of 0.25 and 0.5% citric and phytic acids on color and quality properties of doenjang during fermentation at $30^{\circ}C$ for 80 days were evaluated. As concentration of organic acid and fermentation time of acid-added doenjang increased, acidity, lightness, and antibrowning rate increased, whereas pH, amino nitrogen, and enzyme activity decreased compared to nonacid-added control. Microbial populations of total bacteria, yeast, and lactic acid bacteria were not affected by decrease in pH. Although degree of brown color (p<0.05) could be differentiated, flavor, palatability, acid taste, and overall preference were not significantly different. Browning of doenjang added with 0.25% of either organic acid was inhibited, while quality properties and sensory characteristics were similar to those of the control.

• Food Science and Preservation
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• v.10 no.2
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• pp.136-141
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• 2003

This they was conducted to investigate the surface treated effect of Packaged kimchi on the PH, acidity, total microbe, number of lactic acid bacteria, browning and formation of off-flavor during storage at 10$^{\circ}C$. Kimchi was treated with 70% ethanol(1 time spraying) and attachment of polyethylene film(PE) on the surface of packaged kimchi and stored at 10$^{\circ}C$. pH of the control and ethanol treated kimchi stored for 15 days was decreased to 4.0 level but, the pH of PE-treated kimchi maintained over pH 4.0 until 21 days of storage. The aridity was the same tendency as the pH, which showed delaying of fermentation by PE treatment. Total microbe of PE treated kimchi was lower and number of lactic acid bacteria was higher than those of control and ethanol treated products, respectively. Degree of browning and off-flavor of control and ethanol treated kimchi increased from 13 days of storage, but the degrees of the PE-treated kimchi was lower during all storage periods.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.295-303
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• 2007

As a result of life-style changes, consumer's concerns of food have shifted from calories and nutrition to health and convenience. Fresh-cut products are one such new direction for fruit and vegetable consumption. In this study, the vitamin C, mineral, and pesticide contents of various fresh-cut products were analyzed. According to sensory evaluations, the key reason for a lower than expected overall acceptability of many fresh-cut products is that they are likely to have browning and can easily lose their freshness. Also, the sensory evaluation showed that shriveling, the degree of browning, softening around the cut edge, and off-flavors were the primary factors affecting the quality of fresh-cut products. As a nutritional factor of quality, vitamin C content was not practical with regard to fresh-cut lettuce because the level was very low. For product safety, residual pesticides were detected in the fresh-cut products, but the results showed that all items were under permitted levels and considered safe. In evaluation of the microbial levels of the fresh-cut market products, the levels of viable cells, mold, yeast, coliform bacteria, and enterobacteriaceae were not significantly different based on the summer and winter seasons. The levels of S. aureus and Listeria spp. in the products were higher during the summer season than the winter.