• Food Science and Preservation
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• v.8 no.4
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• pp.367-373
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• 2001

In order to study the effect of modified atmosphere storage on extending shelf life of King Oyster mushroom was wrapped with PVC film and packed with 20$\mu\textrm{m}$polyolefin(PD941), and effects of temperature(0, 5, 10$^{\circ}C$) in packaging conditions on the respiration and keeping qualities were evaluated. Higher respiratory activity and weight loss were observed at higher temperature. The concentration of O$_2$and CO$_2$ of PVC wrap and polyolefin(PD941) packages for all showed 1∼2% and 10∼14%, respectively. Polyolefin(PD941) package wan superior to the PVC wrap packaging method in Hardness, Hunter L value, Hunter b value and sensory qualities, and reducing weight loss at 0$^{\circ}C$, 5$^{\circ}C$ and 10$^{\circ}C$ compared to PVC wrap. It was found that the optimum shelf-life period of King Oyster mushroom packaged by PVC wrap was estimated to be 50, 28 and 12 days at 0, 5 and 10$^{\circ}C$, respectively, and 50, 32 and 21 days in Polyolefin(PD941).

• Food Science and Preservation
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• v.23 no.6
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• pp.832-838
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• 2016

The purpose of this study was to investigate the effect of a fresh chlorella powder on yield, quality and self-life of organic soybean tofu. After added with a fresh chlorella powder, yields, physical properties, color, shelf-life and sensory properties of the organic soybean tofu added with chlorella powder was compared to the properties of soybean tofu. The yield of soybean tofu increased with the addition of more than 1% chlorella powder. Hardness of the organic soybean tofu with chlorella significantly increased compared to that of the soybean tofu. However, Hunter's color values of L, a, and b decreased by increases in the chlorella powder concentration. Total microbial population of the soybean tofu was higher than that of the organic soybean tofu with chlorella. However, pH of chlorella tofu decreased during storage period at $4^{\circ}C$. After 7 days storage at $4^{\circ}C$, the total microbial population decreased significantly with the addition of 2% chlorella powder. The L and a value of chlorella tofu was increased. On the other hand, the b value of chlorella tofu was decreased during storage. The results revealed that a fresh chlorella powder was a useful material to improve yield, quality and storage condition of the organic soybean tofu.

• Food Science and Preservation
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• v.9 no.2
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• pp.154-160
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• 2002

This study was carried out to investigate the efficacy of electrolyzed oxidizing(EO) water, electrolyzed oxidizing water with 0.5% citron juice and 0.1% aluminium potassium sulfate (APS) solution as the storing liquids to maintain quality and extend shelf life of peeled taro. Water content of peeled taro increased from 80.55% to 82.12∼84.24% after 25 days storage due to moisture absorption. However, there were no significant difference between treatments. In case of color value of peeled taro, L value was slowly decreased and a, b value was generally increased. Texture of peeled taro decreased from initial 4,520$\pm$75 g to 4,160$\pm$80 g after 25 days storage in EO water with 0.5% citron juice, which is the least reduction value in all treatments. Treatment of EO water with 0.5％ citron juice maintained 6.99 mg%(57%) of total vitamin C after 25 days storage which showed highest total vitamin C content between treatments. In most treatments, total sugar was decreased in fast rate for 15 days storage and slowly decreased after 15 days storage. Free sugar content was not changed significantly during storage. In case of sucrose content which is the major portion of free sugar, reduction continued until the midst of storage. and after that it increased to 1.5∼2 times of initial contents. However, there were no differences between treatments and storage days in contents of fructose, glucose and maltose. Major amino acids in peeled taro were aspartic acid and glutamic acid with 1,084.8 and 691.8 mg/100g respectively. At 25 days of storage, aspartic acid content in treatment of EO water was increased about 13.9%. Treatment of EO water with 0.5% citron juice was the most effective in respect to the reduction ratio of total amount of essential amino acids.

• Food Science and Preservation
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• v.15 no.4
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• pp.491-496
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• 2008

To develop a freshness indicator of Chonggak-kimchi for marketing purposes, Chonggak-kimchi was prepared and pH, total acidity, total aerobic bacterial load, lactic acid bacterial levels, and reducing sugar content were measured. Sensory evaluation tests on product stored at $4^{\circ}C,\;10^{\circ}C,\;and\;20^{\circ}C$, were performed. The pH increased slightly early in storage, and then decreased to pH 4.2-4.3 for all samples. The rate of decrease of pH rose with increasing storage temperature. Total acidity values rapidly increased after 1, 5, and 7 days of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively. Populations of total aerobic bacteria and lactic acid bacteria increased slightly until 4 days, 10 days, and 30 days of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively, and then decreased drastically. Sensory evaluation data showed that Chonggak-kimchi was edible until 4 days(pH 4.5), 10 days(pH 4.4), and 30 days(pH 4.3) of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively. These results clearly suggest that the shelf-life of Chonggak-kimchi depends on storage temperature, and the pH limit for marketing is 4.3; this is a freshness indicator for Chonggak-kimchi.

• Food Science and Preservation
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• v.21 no.5
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• pp.601-608
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• 2014

To determine the optimal shelf life for maintaining the high quality of kohlrabi, the changes in the physiological and secondary metabolites of kohlrabi stems during storage were investigated. The results showed that the kohlrabi maintained its marketable quality for two weeks at room temperature and for two months in cold storage ($4^{\circ}C$). Interestingly, the total phenol and flavonoid contents sharply declined along with the quality deterioration after two-week storage at room temperature. Moreover, insignificant changes in these compounds were observed for two months during the cold storage. The secondary metabolites of the kohlrabi were also influenced by its storage condition. The total phenol and total flavonoid contents of the kohlrabi significantly increased with the storage periods at low temperature, and significantly decreased with the storage periods at room temperature. In terms of the packaging, no significant difference in the total phenol content of the kohlrabi was found between the packaged and non-packaged types of storage. However, the flavonoid content of the packaged kohlrabi was higher than that of the non-packaged kohlrabi at the end of their storage. The content of glucosinolates, an anti-cancer ingredient was maintained during the storage, so the vegetables remained good sources of these compounds when stored in cold storage even for a long period. This study showed a close correlation between the secondary metabolites and the change in the quality of kohlrabi during storage. The results also suggested that secondary metabolites such as phenolics can be considered quality indicators of the shelf life of kohlrabi.

• Food Science and Preservation
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• v.21 no.5
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• pp.636-645
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• 2014

Quality changes in frankfurter sausages with yam (Dioscorea japonica) powder added were investigated during their storage at $10^{\circ}C$ for six weeks. The sausage samples were prepared using four concentrations of yam powder: 0% (C), 0.5% (T1), 1.0% (T2), and 2.0% (w/w) (T3). After the addition of yam powder, the crude protein contents decreased, but the crude fat and carbohydrate contents increased. The thiobarbituric acid values during the storage of the frankfurter sausages were lower in the samples with higher yam concentrations. Over the storage period, the volatile basic nitrogen values increased with the increase in the amount of added yam. With the increase in the yam concentration, the $L^*$ and $a^*$ values tended to decrease, whereas the $b^*$ value increased. The instrumental texture analysis showed that the hardness value decreased with the increase in the yam concentration. The first indication of sensorial quality deterioration was noticed at week 4 for T3 and at week 5 for C, T1, and T2. In conclusion, the quality and shelf-life of the frankfurter sausages were not noticeably influenced by the addition of yam powder with a concentration of up to 1.0% (w/w), but the functional and health-promoting effects of yam were positively incorporated.

• Hwankyungkyoyuk
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• v.4 no.1
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• pp.89-211
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• 1993

The Korean government embarked upon ambitious economic development plans in the 1960's the goals of development policy at that time were the elimination of absolute poverty and the alleviation of unemployment. With scant natural resources, the government had to push for industrialization based upon borrowed foreign raw materials with surplus local labor. Preoccupation with the economic goals of industrialization and export expansion left little room for considering environmental protection. It is evident that Korea's exported industrialization strategy of the past three decades has been a success in terms of income, production, and other macroeconomic indicators, but it cannot be denied that a host of undesirable side-effects have been created. These include environmental problems. congestion in several large cities, poor wealth distribution, and regional disparities. The environmental problems were recognized even in the early stage of development, but preoccupation with the pending economic goals of industrialization and export expansion left little room for considering environment protection. The perceived and actual seriousness of the problems, however, has reached such a level that further negligence may imperil political stability and developmental problems facing the world arise from a world economic order characterized by ever expanding consumption and production, which exhausts and contaminates natural resources and creates and perpetuates gross inequalities between and within nations. It will be necessary to develop new culture and ethical values, transform economic structures, and reorient, our lifestyles. Changing lifestyles can not be promoted by government policy initiative alone but through self=generated educational efforts and mutual training by people themselves. The citizens group for environment (NGOs) should assume these educational and training responsibilities starting from grass-root level of people. It must be reawakened to the reality that the environmental preservation for better quality of life is based on the development of human relationships, creativity, spirituality, reverance for the natural world and celebration of life, and is not dependent upon increased consumption of non-basic material goods. To carry on such environment education social movements and NGOs should (1) provides educational methodologies, which focus on values clarification and moving beyond clarification and moving beyond blame to constructive action. (2) provide training for leaders of business and industry, government, union and others on consumption and production. (3) initiate and support the training and work of environmental counselor who encourage responsible consumption. (4) cooperative with media to initiate and strengthen educational programs on the social environmental programs on the social environmental impacts of consumption and production and to build awareness of consumer responsibility and potential. Economic and social development can be compatible with environment protection : both can be achieved simultaneously. Effective environmental management depends on the various factors : political will, institutional arrangements, appropriate legislation, and availability of the requistite financial and technological resources, which is possible with a strong public awareness of the importance of environmental preservation.

• Food Science and Preservation
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• v.21 no.2
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• pp.157-162
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• 2014

To enhance the commercialization of fresh cut kimchi cabbage, the short-term storage effect of cut kimchi cabbage treated with $Ca^{2+}$ was studied. Cut kimchi cabbages ($3{\times}3$ cm) were treated with 2% calcium chloride (Ca), ascorbic acid (As), citric acid (Ct), and calcium chloride and citric acid (Ca/Ct), were put inside LDPE bags, and stored at $5^{\circ}C$ for 6 weeks. The weights reduced about 0.13~0.72%, and the ratio was the lowest in the Ca/Ct treatment. The reduction ratios of soluble soilds were 18.85~35.00%, and were the lowest in the Ca/Ct treatment. The titratable acidity decreased in all the treatments. The L values decreased, but a and b values of Hunter colorimeter increased in all the treatments. The preference for Ca/Ct treatment was the highest among all the treatments in the sensory evaluation. The marketing shelf-life of cut kimchi cabbage can be prolonged by the combination treatment of $Ca^{2+}$ and citric acid.

• Food Science and Preservation
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• v.14 no.4
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• pp.345-350
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• 2007

Shelf-life and quality changes of four leaf lettuce cultivars packaged and stored at four different temperatures (0, 8, 16 and $24^{\circ}C$) were evaluated. Leaf lettuces were packaged in non-perforated polypropylene film (thickness 0.05 mm) bags. Weight loss, respiration rate, freshness degree, pigment content, and surface color were determined. At the storage temperature of $0^{\circ}C$, the weight loss, degree of freshness, pigment content, and change of surface color on packaged leaf lettuces showed no significant difference when compared with all other leaf lettuces. Meanwhile, an increase in storage temperature was observed with the quality changes of each flesh leaf lettuce. The leaf lettuces under storage conditions at $24^{\circ}C$ showed a difference in weight loss of the different types of leaf lettuces during a short storage period. However, there was no clear tendency in weight loss in different types of leaf lettuces as compared with each storage temperature. The rate of respiration and the contents of pigments in the four types of leaf lettuces also showed significant difference as the storage temperature increased.

• Food Science and Preservation
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• v.20 no.1
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• pp.23-29
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• 2013

To extend the shelf-life of freshly cut lotus roots, the effect of their heat treatment in water at $50^{\circ}C$ was investigated and compared with that of their treatment using 1 percent ascorbic acid and citric acid during their storage. In addition, consecutive heat and acid treatment was applied to freshly cut lotus roots to determine its synergy effect. The level of molds in the sample that was treated with $50^{\circ}C$ water for 60 minutes was the lowest among the treatments and 3.89 log CFU/g after 12-day storage, whereas the population of the control was 6.81 log CFU/g for the same number of days. During the storage, the surface color of the samples showed higher ${\Delta}E$ values and lower L values than that of the initial sample. The color with the heat treatment hardly changed, unlike in the control. The consecutive treatments with hot water and acid showed less quality loss than the simple heat treatment. The marketable quality was maintained for three days without any treatment, for nine days with the heat treatment, and for 12 days with the consecutive treatments of hot water and acid. The consecutive treatments with hot water and acid, especially with 1 percent citric acid, extended the shelf-life of the freshly cut lotus roots by inhibiting the growth of microorganisms and the browning.