• Food Science and Preservation
• /
• v.10 no.1
• /
• pp.16-22
• /
• 2003

This study was conducted to find out effective MA (Modified Atmosphere) gas compositions on the oyster mushroom through statistical analysis of the respiration rate and MA storage for the various packaging materials. Under the various gas compositions, the oxygen consumption rate of oyster mushroom was from 28.9 to 161.4mgO$_2$/kg$.$hr and the carbon dioxide evolution rate was from 53.4 to 166.9 mgCO$_2$/kg$.$hr at 20$^{\circ}C$. The estimated MA condition of oyster mushroom were 2.5∼4.5%O$_2$and 11.5∼l3%CO$_2$by the RSREG(Response Surface Regression). The gas compositions of MA packaging are following that 0.03mm LDPE were 1.6∼3.0%O$_2$and 3.9∼5.3%CO$_2$,0.05mm LDPE were 1.2∼1.3%O$_2$and 9.0∼11.1%CO$_2$and Nylon+PE were 0.9∼1.2%O$_2$and 33.5∼39.6%CO$_2$. The weight loss increased at 0.03mm LDPE but has the lowest value at Nylon+PE. The hardness of pileus and stipe was decreased with storage periods. The $\Delta$E-value increased with storage period and seriously changed in early storage period at 12 and 20$^{\circ}C$. In the 0.05mm LDPE, the gas compositions of packaging were similar to estimated gas compositions from the RSREG and the storage quality was superior to the other packaging materials in weight loss, hardness, and color difference at 4, 12 and 20 $^{\circ}C$.

• Journal of the Korean Society of International Agriculture
• /
• v.23 no.5
• /
• pp.497-502
• /
• 2011

Broccoli is considered as one of the functional foods to offer a hearty supply of the nutrient-rich vegetable in the world. Broccoli contains high level of phytochemicals, and that is selected as one of the top 10 vegetables for human health promotion. Especially, glucosinolates and flavonoids are well known as anti free oxygen radicals in vegetables and fruits. In Korea, broccoli consumption has increased to well known on the health-beneficial vegetables since 2000. However, broccoli has many problems of postharvest management since the quality of harvested heads quickly declines. Major problems are the floret yellowing, wilting, off-odor, and decay. The multiple postharvest applications improve broccoli quality and cold treatment including pre-cooling extends on the shelf-life with circumstance of optimum storage which is 0℃ temperature and a range of 95-100% relative humidity. Controlled atmosphere or modified atmosphere packaging can be used as supplemental treatments to extend postharvest life. 1-2% O₂ + 5-10% CO₂ is currently recommended for broccoli. Postharvest management is important for broccoli because price fluctuations depend on harvest time and quality. In this study, we tried to review physiological change of broccoli after the harvest, storage method, and various techniques to optimize quality during distribution.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.3
• /
• pp.478-486
• /
• 2017

To find the effect of packaging materials(LDPE $60{\mu}m$, Ceramic $30{\mu}m$ and $60{\mu}m$) to enhance the shelf-life of de-astringent persimmon, the fruits used were the astringent persimmons of "Cheongdobansi" and astringency was removed in $CO_2$. De-astringent persimmon were stored in MA for 140 days at $5^{\circ}C$. During storage, the concentration of oxygen was decreased to 5.2%, while the concentration of carbon dioxide was increased to 5.2% from 18 days. But the concentration of oxygen and carbon dioxide was maintained at a constant concentration until the end of storage. The rate of weight loss was gradually decreases for the storage time elapsed and has better in ceramic $60{\mu}m$ packaging than other packaging materials. Fruit hardness and color value were well maintained in ceramic $60{\mu}m$ packaging. Tannin content and soluble solid were not significant difference among the packaging conditions. Ethanol and acetaldehyde content were decreased during early period of storage and then increased. As a result of objective analysis, de-astringent persimmon storage in ceramic $60{\mu}m$ was more effective than other storage conditions.

• Food Science and Preservation
• /
• v.6 no.4
• /
• pp.351-356
• /
• 1999

To develop and extend the shelf-life of vitamin C enriched fresh-cut apples using CA stored Fuji apples, dipping in 10% L-ascorbic acid and packaging with 0.03 mm LDPE, 0.04 mm PP and 0.08 mm Nylon/PE film(N$_2$displacement) were carried out. The changes of gas concentrations in the packaging and quality attributes of fresh-cut apples were examined during storage at 10$^{\circ}C$. The concentrations of O$_2$was maintained lower in Nylon/PE film than the other film, the level of O$_2$was in the range of 1∼3%. The increase of C$_2$H$_4$ concentrations in Nylon/PE film bag was more suppressed than the others. The vitamin C content of fresh-cut apples was enriched by dipping in L-ascorbic acid solution up to 241 mg$.$100 g-1 f.w., and the loss or that content was retarded differently by the package conditions of lower O$_2$level during storage. Browning in fresh-cut apples was shown after 6 days of storage in LDPE and PP film. but it was not shown by 14 days of storage in Nylon/PE film. Spoilage and off odor in fresh-cut apples were not detected up to 14 days of storage in Nylon/PE film. The results indicated that the vitamin C enriched fresh-cut apples can be processed from the long-term CA stored apples, and maintaining high quality of the products ill be possible in cases of the application of sealing packaging after O$_2$removal with film having low O$_2$permeability.

• Journal of Bio-Environment Control
• /
• v.29 no.3
• /
• pp.239-244
• /
• 2020

Effect of 6kg large unit with the carton box (20% open ratio) and MA box (10,000cc·m^-2·day^-1·atm^-1 oxygen transmission rates modified atmosphere package), and the 100g small unit with MA film on asparagus sensory quality were evaluated. The CO₂ concentration depended largely on the packing unit and maintained at around 3% in small MA packages, whereas in the MA box increased to 12%. Ethylene concentration rapidly increased until after 3 days of storage in MA packages and then decreased to maintain 5μL·L^-1. Unrelated to the unit size, the lower weight loss was obtained in MA packages. A significant difference in visual quality was shown since the 15th day, the best and worst were the MA box and small MA package on the finish day. Off-odor was the highest in small MA packages and the lowest in the carton box (< 3.0). Although there was no significant difference in firmness among all treatments, the packages showed the highest firmness in tips and stems, respectively. The sugar content and hue angle decreased during storage, but there was no statistical difference in all treatments. EL was lowest and highest in small MA package and carton box, respectively. On the 10th day, the total aerobic bacteria was lowest in small MA packages, but no significant difference on the 20th day. E. coli was not found in all treatments on the 10th day, while it was the lowest in the MA box on the 20th day. The mold and yeast were not observed during the whole storage. Based on the above results, the carton box packaged with 10,000cc OTR film was more effective in maintaining the quality of green asparagus with the suitable CO₂ concentration for asparagus cold storage.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.1
• /
• pp.135-140
• /
• 2014

Pre-storage ultra-violet (UV) light treatment on fresh produce is known to inactivate the contaminated microorganisms, activate the defense system, and delay ripening extending the shelf life. As UV light emitting diode (LED) becomes available at a relatively low price, continuous or intermittent UV treatment during chilled storage is possible in a container or package. This study attempted an in situ UV LED treatment on fresh produce stored under a refrigerated container in order to see its potential in the fresh produce storage and further optimize its application conditions. The effect of in-container UV LED irradiation on the quality preservation of shredded carrots was investigated in the air and modified atmosphere (MA) conditions. Two sets of experiment with Escherichia coli inoculation and with natural microbial flora in the air (two 30 minute on-off cycles of 1 $diode/dm^2$ per day at a location above 2 cm) showed a clear and significant effect of the UV LED irradiation on the suppression of microbial growth: 280 nm was the most effective by maintaining a lower microbial count by at least 0.5 log (CFU/g) throughout the 6 day storage period. The carotenoids content of shredded carrots subjected to UV LED treatment at 365 and 405 nm in the air was higher than that of the control shredded carrots. In MA condition of $O_2$ of 1.2~4.3% and $CO_2$ of 8.4~10.6% being indifferent with LED wavelengths, 280 nm UV LED irradiation was also effective in inhibiting the microbial growth. While there was no observed difference in the carotenoids content between untreated and UV LED-treated shredded carrots in MA, UV LED irradiation at 365 and 405 nm was slightly better in DPPH radical scavenging activity. The use of UV LED in storage container or package seems to give the benefits of preserving the microbial and nutritional qualities of minimally processed fruits and vegetables.

• Food Science and Preservation
• /
• v.23 no.5
• /
• pp.605-613
• /
• 2016

The quality and shelf life of sliced root of Platycodon grandiflorum (Doraji) treated by ozon-microbubble-heat shock (OMH) were investigated by combining modified-atmosphere packaging [MAP, ($50%O_2+15%CO_2+35%N_2$)]. The study was based on microbiological (total viable bacteria, fungi, Enterobacteriaceae and coliforms numbers), physicochemical and sensory changes. OMH treatment was effective in reducing microbial populations of the sliced Doraji, especially Enterobacteriaceae and coliforms reduced by 2 log CFU/g. However OMH-MAP treatment remained the aerobe and fungi numbers. Regarding the color, OMH-MAP delayed the change of Hunter $b^*$ and the sliced Doraji by OMH-MAP treatment exhibited lower decrease of flavor and overall acceptability compared to those by polypropylene packaging after tap water treatment (Control). The OMH and $50%O_2+15%CO_2$ MAP treatment gave better sensory quality and extended shelf-life for sliced Doraji (~3 days longer shelf-life than Control). Flavor was significantly related to overall acceptability at both Control and OMH-MAP, whereas total coliforms prevalence was associated with overall acceptability at only OMH-MAP. Therefore microbubble-heat shock treatment may improve microbial safety and sliced Doraji by OMH treatment can stored under $50%O_2+15%CO_2$ treatment for up to 7 days. Thus, OMH and MAP treatment may be used in maintaining the storage quality and marketability of sliced Doraji.

• Food Science and Preservation
• /
• v.24 no.6
• /
• pp.727-733
• /
• 2017

We investigated the effect of PE film thickness on the modified atmosphere packaging (MAP) deastringency of 'Sanggamdungsi' (Diospyros kaki cv.) astringent persimmon at room temperature ($25^{\circ}C$) and low temperature ($-1^{\circ}C$). The fruits were individually packaged with PE film of which the thickness is 60, 80, 100, 115 or $130{\mu}m$ and stored at room or low ($-1^{\circ}C$) temperature. At room temperature, firmness shows the highest value (23.3-26.5) at $100{\mu}m$ thickness. Top flesh browning and decay was monitored at 20 days after storage, and peel blackening and style-end softening was negligible at optimal thickness. Therefore, optimal film thickness of deastringency at room temperature is $80-100{\mu}m$. At this thickness, the astringency was removed after 5 days and the fruits can be distributed until 10 days after the MAP. At low ($-1^{\circ}C$) temperature, firmness was maintained regardless of film thickness. However, the firmness is higher as the film is thicker. Top flesh browning and decay was not occurred even after 90 days after storage. Peel blackening and style-end softening was monitored at 90 days after storage. Off-flavor was monitored at 115 and $130{\mu}m$ thickness. Therefore, optimal film thickness of deastringency at low ($-1^{\circ}C$) temperature is $80-100{\mu}m$. At this thickness, the astringency was removed after 50 days and the fruits can be distributed until 80 days after the MAP.

• Food Science and Preservation
• /
• v.16 no.6
• /
• pp.817-823
• /
• 2009

We investigated the effects of storage temperature and packaging treatment on the freshness of high-quality 'Fuji' apples to improve consumer confidence in the maintenance of high fruit quality during distribution. A 0.35 mm-deep PET tray form-sealed with a 0.05 mm LDPE film lid was developed and tested with the aim of optimizing gas composition within the package headspace to utilize potential modified atmosphere (MA) storage to maintain the freshness of apples. Weight loss, color difference, firmness, respiration rate, gas concentrations in packages, acidity, solid soluble content, and fruit decay rate were measured during storage at $5^{\circ}C$ and $25^{\circ}C$. The results showed that respiration rate, weight loss, color difference, and firmness were lower and overall quality better during storage at $5^{\circ}C$ compared with $25^{\circ}C$. Also, the fruits packed in the functional tray form showed a low level of quality changes compared with the control (no packaging). The accumulated gasconcentrations in the headspace of the packages decreased from 21% to 12% $O_2$ and increased from 0% to 5% $CO_2$ (v/v) on day 7, and after remained at those levels thereafter. Soluble solid contents and total acidities of the packaged fruits were in the range of $11\;-\;14^{\circ}Brix$ and 0.2 0.3% during storage. Decay rates in the control and packaged fruits were more than 20% and less than 10% at 3 weeks, respectively. Based on the standard acceptable level (less than 10%) of total weight loss, it could be estimated that the shelf life of top-quality fruits packed in functional trays was 3 weeks at $5^{\circ}C$ and 16 weeks at $25^{\circ}C$, whereas the shelf life of the control fruit was 1 week and 12 weeks, respectively. For the top-quality fruit "Fuji" apples, the best results were obtained with a functional tray form for packaging treatment and a storage temperature of $5^{\circ}C$.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.22 no.3
• /
• pp.79-84
• /
• 2016

A kimchi container actively controlling $CO_2$ concentration by timely flushing of $CO_2$ gas was structured and tested in its capability and effectiveness because high $CO_2$ concentration enhances the sensory flavor of the product. The inlet and outlet valves of $CO_2$ gas were programmed to open and close allowing synchronous vent/$CO_2$ flush according to the requirements of its dissolution in the contained kimchi. During the chilled storage, the headspace of container could be maintained at desired high $CO_2$ concentration providing the preferred kimchi in sensory quality compared to control of the conventional container. However, there was no significant difference between the high $CO_2$ container and control (container simply closed with air) in kimchi quality attributes of pH, titratable acidity, total viable bacterial count, Lactobacillus sp. count and Leuconostoc sp. count. The flow rate and time interval of $CO_2$ flushing need to be adjusted considering the kimchi amount, headspace volume and ripening time. The designed system has potential to be applied in refrigerator appliances in homes and food service industry.