• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.71-81
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• 2018

$CO_2$ concentration has a significant effect on quality of cold-stored apples. High indoor $CO_2$ concentrations above 10,000 ppm cause the browning of apples and result in economic loss for farmers. The purpose of this study is to evaluate $CO_2$ concentrations and their distribution in a controlled atmosphere (CA) storage and provide better structural designs to improve the $CO_2$ environment using computational fluid dynamics (CFD) simulations. The CFD model was developed for a real CA storage for apples and applied to investigate the effect of changing the inlet and outlet locations and the aspect ratio of the floor of the CA storage on the spatial distributions of $CO_2$ concentration and the browning of the apples. The lowest $CO_2$ concentrations in existing CA storage with a high aspect ratio of the floor were achieved from the combination of the inlet located at the top of the right side and the outlet located at the bottom of the left side. In modified CA storage with a low aspect ratio, the combination of the inlet and outlet located at top and bottom of left side respectively achieved the lowest $CO_2$ concentrations. The proposed case enhanced the storage performance by reducing total browned apples by 3.6% in storage duration of 210 days. This study is expected to reduce the browning damages of apples in CA storage, and thus greatly prevent economic losses.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.1002-1006
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• 2007

Twenty four broilers (Ross) and 24 ducklings (Cherry berry) aged 45days were stunned and killed by conventional neck cut to evaluate the meat characteristics and fatty acid composition of breast meat. Breast meats were removed from each carcass at different post-mortem times. After complete processing, the breast meats were then placed in a polythene bag and kept in a cold storage room at $4^{\circ}C$ for 7 days. The pH of meat samples at different post-mortem times, and meat characteristics and fatty composition at different storage times were evaluated. No significant differences were found in pH at different post-mortem times except at 30 min postmortem, where duck breast showed significantly lower pH than chicken breast. As expected, duck breast meat had significantly higher redness (a*), but lower lightness (L*) value compared to chicken breast. During whole storage time, the a* value remained constant in duck breast. Cooking loss (%) was higher in duck breast compared to chicken breast during the whole storage time. Shear force decreased with increasing storage time in both chicken and duck breast meat, moreover, it decreased rapidly in duck breast compared to chicken breast. The TBARS values increased with increasing storage time in both duck breast and chicken breast meat and was significantly higher in duck breast. The fatty acids (%) C14:0, C16:0, C16:1, C18:2 and C18:3 were significantly higher while C18:0 was significantly lower in duck breast compared to chicken. SFA was increased, while USFA and MUSFA decreased only in duck breast during the 7 day storage time.

• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.23-31
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• 1969

Whole cure shrimp, eviscerated common squid and little squid meats were irradiated with gamma radiation from 60Co using varying dose up to one Mrad. Changes in quality were assessed by organoleptic, chemical (VRS and TMA-N), biochemical (hypoxanthine) and microbiological tests； and the effect of radiation on prolonging of the storage life at 2-4 C was studied. With the cure shrimp, 0.12-0.20 Mrad appears to be optimal with 8 days of storage life, whereas the unirradiated control samples had a storage life of 3 days. With the common squid meat, 0.20-0.30 Mrad appears to be optimal with 14-21 days of storage life, where-as the unirradiated control samples had a storage life of 8 days. And for the little squid meat, 0.12-0.20 Mrad appears to be optimal with 10 days of storage, where-as the unirradiated control samples had a storage life of 5 to 6 days.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.744-750
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• 2006

An experiment was carried out to evaluate the effects of substituted conjugated linoleic acid (CLA) for fat on qualities, lipid oxidation and residual nitrite contents in emulsion-type sausage (ETS) after different periods of storage. The control sausage contained 20% fat, however, the substituted CLA for fat sausages contained 17.5% fat+2.5% CLA, 15% fat+5% CLA, 12.5% fat+7.5% CLA and 10% fat+10% CLA, respectively. CLA concentration was significantly increased (p<0.05) by substitution of CLA sources for fat, and storage did not affect the CLA concentration. TBARS were significantly increased with the increasing of storage time in all treatments (p<0.05). Significantly higher $L^*$ values were observed in the 10% CLA treatment compared to other treatments during storage. Moreover, $a^*$ values in CLA treatments significantly (p<0.05) increased compared to the control. Again, $b^*$ values were significantly (p<0.05) higher in CLA treatments than those of the control during storage. The concentration of residual nitrite in ETS was significantly (p<0.05) different between the treatments during storage and the results were in the following order: control >2.5% CLA>5% CLA and 7.5% CLA>10% CLA. Overall acceptability of CLA treatments was significantly (p<0.05) lower than the control during storage, whereas no significant differences were found in overall acceptability between the treatments after 28 days of storage.

• Herbal Formula Science
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• v.19 no.1
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• pp.183-194
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• 2011

Objectives : To estimate the shelf-life by long-term storage test of Pyungwi-san. Methods : Experiments were conducted to evaluate the stability such as the selected physicochemical, heavy metal, microbilogical experiment under an acceleration test and long-term storage test of Pyungwi-san in different storage under room temperature, refrigeration and freezing. Futhermore, HPLC analysis was performed for the determinations of glycyrrhizin in the Pyungwi-san on an Inertsil ODS-3 column(250 mm ${\times}$ 4.6 mm, 5 um) using solvent 35% acetonitrile include 0.05% phosphoric acid at 254 nm. The flow rate was 1.0 mL/min. Results : The significant change was not showed in pH, heavy metal, microbiological, identification test and quantitative analysis based on acceleration test and long-term storage test. Retention time of glycyrrhizin in HPLC chromatogram was about 16.065 min and calibration curve showed good linearity($R^2$ = 0.9999). The contents of glycyrrhizin in acceleration test and long-term storage test were 0.068~0.076 mg/mL and 0.066~0.077 mg/mL, respectively. Shelf-lifes of room temperature, refrigeration and freezing by long-term storage test were predicted 41, 24 and 34 months, respectively. Conclusions : The suggested shelf-life would be helpful on the storage and distribution of herbal medicine.

• Food Science and Preservation
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• v.11 no.1
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• pp.7-11
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• 2004

To examine the effect of storage condition on the quality and microbiological change of strawberry “Minyubong”, the rate of weight loss, decay rate, pH and titratable acidity, and microbial (total bacterial count, mold and yeast) changes were determined during storage. Strawberry fruits were packaged with low-density polyethylene (LDPE). Strawberries were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was effective on the decrease of decay rate of strawberry as well as the rate of weight loss, compared with the non-packaged. Microbial changes of strawberry stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging affected the microbial change, resulting in retarding the growth of total bacteria as well as mold and yeast, compared with the non-packaged, regardless of storage temperature. These results indicate that storage of strawberry fruits wrapped with LDPE at 4'C should be recommended in terms of quality as well as its shelf-life.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.3
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• pp.265-274
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• 2004

To investigate the effect of cereal powders on the quality and storage characteristics of sausage, Aw, pH, microbial count, TBA value, VBN value, textual and sensory characteristics were examined. Water activity tended to decrease as storage time prolonged and all the samples showed higher Aw's than that of the control. During the storage period, pH values of all the samples decreased. L, a and b values had a tendency to decrease during the storage period. During the four weeks storage at 4$^{\circ}C$, TBA and VBN values of all the sample showed increasing tendency and were lower than those of the control. Total plate counts of bacteria, the number of lactic acid bacteria and coliform bacteria counts increased as the storage time prolonged. Texture characteristics of all samples increased up to 1 week storage and decreased subsequently. The sensory scores of all the samples decreased as the storage time prolonged.

• The Korean Journal of Mycology
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• v.39 no.2
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• pp.151-153
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• 2011

In order to optimize storage conditions of Korean traditional Makgeolli, we brewed Korean traditional Makgeolli for 1 week with two-stage fermentations and investigated changes viable cell counts of yeasts and bacteria during storage for 1 month at $4^{\circ}C$ and $20^{\circ}C$. Yeast viable cell counts were decreased to 89.0% after storage for 30 days at $20^{\circ}C$, however, those were not significantly changed at $4^{\circ}C$ storage. Bacteria cell counts were decreased to 59.0% of initial cell counts for 30 days at $4^{\circ}C$. In the storage at $20^{\circ}C$, bacteria were significantly decreased to 98.0% of initial cell counts after storage for 30 days. Lactic acid bacteria were also similar to those of total bacteria cell counts at $4^{\circ}C$ storage, however, 99% of lactic acid bacteria were decreased at $20^{\circ}C$ storage for 30 days.

• Food Science and Preservation
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• v.5 no.1
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• pp.23-28
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• 1998

The objective of this study was to investigate the methods of quality maintenance using modified atmosphere packaging with various quality preservatives at ambient and low temperatures. Ethylene(<1.0ppm) accumulated during modified atmosphere storage of Chinese cabbage using polyethylene film(60$\mu\textrm{m}$) caused quality deterioration such as yellowing and abscission. The addition of potassium permanganate reduced ethylene level and thus extended storage life of l00% at 20$^{\circ}C$ and 140% at 0$^{\circ}C$. To establish the storage conditions of minimally processed sit and vegetables, the experiment was conducted with various quality preservatives and packaging materials. Ceramic film(Zeolite 7%, 60$\mu\textrm{m}$) showed increasing storage life of 50%, reducing total microbial counts of 50% and keeping high appearance quality of minimally processed pears stored at 20$^{\circ}C$ and 0$^{\circ}C$. Minimally processed Chinese cabbage treated with l% CaCl2 at 20$^{\circ}C$, and 1% CaCl2 and 1% NaCl at 0$^{\circ}C$ has a longer storage life of 90% with good maketable quality. Treatment of 1% NaCl for cut Asian penis appeared increased storage life of 100%, decreased cut surface browning and the best overall acceptability by a sensory panel.

• Food Science and Preservation
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• v.1 no.2
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• pp.81-86
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• 1994

This study examined the quality change of red peppers during storage at various temperatures and humidities. It was observed that red peppers showed mold at aw 0.75(>25% water content), discoloration at aw 0.33(<10%) and browning at aw 0.75(>19%). The most ideal condition of the storage for red peppers was a 13∼15% water content and 60${\pm}$5% RH. The storage life for whole red peppers were 2.0 months at 40$^{\circ}C$, 13.6 months at 25$^{\circ}C$, 27.3 months at 15$^{\circ}C$, 30.0 months at 10$^{\circ}C$, and 65.0 months at -3$^{\circ}C$. During any storage period above, level of capsanthin, browning and capsaicin were changed for whole peppers. Browning appeared to be a crucial factor for marketable quality of stored red peppers. It was found that the level of capsaicin & capsanthin have a miner relationship with marketable quality for consumer. Storing red peppers in nitrogen and vacuum atmosphere packing condition was found to be better than storing them in air at various temperatures in terms of storage life and quality maintenance. The nitrogen gas packaged red peppers kept longer shelf life and better quality compared with vacuum packaging.