• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.230-236
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• 2000

For extension of storability, onion bulbs produced in Cheju Island were exposed to ${\gamma}$-ray irradiation at a dosage of 0, 3, or 6Krad and stored in a natural cavern, or in low (2$^{\circ}C$) or ambient temperature storage condition. Sprouting began from approximately five months in storage, regardless of storage condition, and increased as the storage period increased. From early August, sprouting as high as 50% occurred in the natural storage cavern, and 20% in ambient temperature storage when bulbs were treated with 0 krad ${\gamma}$-ray. However, bulbs treated with 3 or 6krad ${\gamma}$-ray did not any sprouting until six months in storage. No significant weight loss was observed in all treatments until sprouting occurred from 40 days after the initiation of storage. Weight loss, however, increased remarkably after 40 days in storage, indicating that it was closely related to sprouting during storage. Bulbs stored at 2$^{\circ}C$ showed 5~10% rot, but were still edible. Percent rot reached to as high as 50% in bulbs unirradiated and stored at ambient temperatures after seven months, while it in irradiated bulbs reached to 5, 33, and 30% at 2$^{\circ}C$, in a natural cavern, and ambient temperatures, respectively. Sugar contents slightly increased in irradiated bulbs in the later storage period under ambient temperatures, while sugar contents in irradiated bulbs in the later storage period under ambient temperatures, while sugar contents in Allium vegetables generally decrease in later storage if unirradiated. Sulfur content slightly increased in irradiated bulbs in the early storage period and decreased gradually in all treatments in the later storage stage.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.115-119
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• 2000

Oak mushroom(Lentinus edoes(Berk) Sing) is one of the most important edible mushrooms, and its production has been rapidly increased due to nutritional and medicinal effects. In this study, climatic factors during the growing period of high-quality oak mushroom were analyzed and environmental factors affecting the quality of oak mushroom were discussed. Three places(Changheung, Puyo and Wonj) as mass producing areas of high-quality oak mushrooms and the 15 days of the growing period in 1997-1998 were selected. Major climatic factors for analysis were average air temperature, average relative humidity, ranges of daily air temperature, relative humidity, and wind speed. During the period, th daily average air temperature was $7~20^{\circ}C$ with the diurnal air temperature($7~20^{\circ}C$) and nocturnal air temperature($0~-2^{\circ}C$). The relative humidity ranged between 50 and 70% with the range of daily relative humidity(40~60%). Wind velocity was 1~4m.$s^{-1}$, From the results, it is concluded that the growing environmental conditions for high-quality oak mushroom differed from the optimum conditions for the high productivity of oak mushroom; environmental conditions such as wide ranges of air temperature and relative humidity, low humidity and wind speed might affect the emergence of high-quality oak mushroom.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.156-161
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• 1999

This study was conducted to investigate the effects of n-capric acid(CA) or n-capric acid methyl ester (CE) addition during salting process, and fermentation temperature on chemical and microbial changes of Kimchi. The pHs of control, CA and CE were 3.78, 4.28 and 4.35 after 6 days of storage at $20^{\circ}C$ and were 3.85, 5.14 and 5.10 after 42 days of storage at $4^{\circ}C$, respectively. The effects of CA or CE addition at $4^{\circ}C$ were higher than those at $20^{\circ}C$. The maximum edible acidity, 0.75%, was reached within 3 days at $20^{\circ}C$, 15 days at $12^{\circ}C$, and the acidity of 42 days at $4^{\circ}C$ was 0.62% which was still lower value than the maximum edible acidity. Total bacteria, Leuconostoc, Lactobacillus and yeast counts of the control were higher value than those of the treatments throught the whole fermentation period. The addition of CE at $4^{\circ}C$ had much affected the reduction of yeast count. As microbial counts and reduction rates of control and treated Kimchi increased with increasing the storage temperature.

• Journal of Life Science
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• v.27 no.10
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• pp.1185-1190
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• 2017

Insects are gaining recognition as an alternative source of protein. As a result, more and more domestic farms have begun mass rearing of edible insects. In order to produce high quality insects, studies on the development of safe and nutritious feed sources are needed. Given the cost of rearing insects, agricultural and industrial by-products are good sources for feed. The efficient utilization of these by-products can help in reducing the cost of production and preventing environmental pollution. In the current study, Citrus unshiu peel (CP), soybean curd cake (SCC), soybean oil meal (SOM), and brewers dried grain (BDG) were investigated for their effects on larval growth and development of Protaetia brevitarsis. Interestingly, the feed with 10% SCC increased larval weight by 3.5 times. For the larval period, the group of 10% SCC was significantly shorter than the control. Furthermore, minerals such as Zn, Ca, K, Mg, Na, and P were recorded to be high in 10% SCC. A total of 17 amino acids were present in 10% SCC, of which tyrosine and arginine were predominant. The heavy metal contents were very small amounts or not detected in any of the investigated groups. These findings provided a scientific basis for the utilization of soybean curd cake as a nutritional feed source to promote larval growth and produce quality insects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.1-7
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• 1998

Uronate compositions and molecular weights of alginates from the four kinds of brown algae, sea mustard (Undaria pinnatifida), sea tangle (Laminaria japonica), gulf weed (Sargassum fulvellum), and seaweed fusiforme (Hizikia fusiforme), in regard with the harvesting season were investigated. Sea mustard contained the highest amount of alginates in the four kinds of brown algae. D-Mannuronic acid to L-guluronic acid (M/C) ratio of the alginates was high in order of seaweed fusiforme, gulf weed, sea mustard, and sea tangle, and especially in water-soluble alginate. Molecular weights of the alginates were greater with the growing period ranging in $4,500\~4,800\;kDa$ for sea tangle, $4,000\~4,200\;kDa$ for sea mustard, $3,300\~3,400\;kDa$ for seaweed fusiforme, and $3,000\~3,200\;kDa$ for gulfweed. In water-soluble alginate of sea mustard, M/G ratio was much higher in sporophyll than in midrib and blade.

• Journal of Life Science
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• v.28 no.12
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• pp.1501-1506
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• 2018

Edible insects have recently been increasingly promoted as a source of protein. As the number of farms rearing these insect increases, it is important to develop safe and nutritious feed sources to improve their commercial quality. The aim of the current study was to determine the effect of food by-products as feed supplements for the Korean rhinoceros beetle, Allomyrina dichotoma, which has been registered as a general food ingredient in Korea. We compared the effects of waste citrus peel, soybean curd cake, soybean oil meal, and brewers' dried grain on the growth of third instar larvae of A. dichotoma. Groups of larvae were fed with fermented sawdust and nine different combinations of the above by-products and the effects on their growth were measured until pupation. The highest survival rate was with feed supplemented with 10% brewers' dried grain (66.7%, p<0.05), and these larvae were also 26% heavier (p<0.05) than the control group that received no supplementation. In the 10% brewers' dried grain group, the larval period of third instar was shortened by almost 28 days (p<0.01) compared to the control group. Of all the groups, only that which was fed the brewers' dried grain supplement showed more than a 90% pupation rate (p<0.05). Therefore, brewers' dried grain may be useful as a source of feed for A. dichotoma.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.374-379
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• 2020

The white-spotted flower chafer (Protaetia brevitarsis) larva is one of the insects widely-used for edible and medicinal purposes in Eastern Asia. As a result of increasing demand for P. brevitarsis, massrearing systems in domestic farms have become necessary. However, the mass-rearing of larvae under confined rearing conditions could provide conditions unsuitable for preventing entomopathogenic diseases. Metarhizium anisopliae is the strongest fatal entomopathogenic fungus against P. brevitarsis. For inhibition of M. anisopliae, we used a Rhus verniciflua Stokes extract that has antifungal components. We investigated the inhibitory effect of the R. verniciflua extract at 1%, 5%, and 10% concentrations. The results showed that a 1% R. verniciflua extract added to sawdust produced a significantly low P. brevitarsis mortality rate. Moreover, extract-treated groups were heavier and had a shorter larval period than those of the untreated group. Consequently, we suggest that using an R. verniciflua extract can reduce the P. brevitarsis fatality rate from entomopathogenic fungi (e.g. M. anisopliae), resulting in more effective mass-rearing systems for P. brevitarsis.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.22-31
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• 1999

Saccharomyces fermentati and Leuconostoc mesenteroides were isolated from a traditional kimchi, and then the Leu. mesenteroides was mutated to the acid-tolerant mutant Leu. mesenteroides M-l00. In the result of growth properties in MRS broth with various pHs adjusted with HCl and acid solution (latic acid:acetic acid=1:2), an acid-tolerant mutant Leu. mesenteroides M-100 showed more increased ability for growth than its wild strain at various temperatures. The strains were used as starters for the fermentation of kimchi. The experiments were performed with classified experimental groups (Group I, control kimchi; Group II, addition of YK-19 only; Group III, addition of M-100 only; Group IV, addition of mixture of M-100 and YK-19), and their pH, total acidity, reducing sugars content, organic acid productivity, organoleptic tests, and microfloral changes were compared. As a result, in pH and acidity, the optimal ripening period of Group IV was about 13.5 days (i.e. from the 8.5 to 22 days of fermentation). This result indicates that the optimal ripening period of Group IV was about 1.5 times longer than that of Group I. Furthermore, Group IV was edible to 28 days of fermentation. In addition, high contents of succinc acid was observed in Group IV. Group IV was also highly ranked on the organoleptic test. During the fermentation of kimchi, the number of Leuconostoc sp. in group I reduced after 7 days; however, the number of Leuconostoc sp. in Group II, III, and IV decresed after 14 days of fermentation. An especially high number of Leu. sp. was observed in Group IV, and this gave better flavor of kimchi than any other during the whole fermentation period. Citric acid, tartaric acid, succinic acid, fumaric acid, and lactic acid were detected in the kimchi, and a significant increase in the concentration of lactic acid during fermentation was observed in the all experimental groups.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.249-255
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• 1998

New drying method was tested comparison with a traditional one used for production of Kwamaegi, semi dry pacific saury in east coast area of Kyungbuk province. During 15 days of total drying period, change in nucleotides and free amino acids were measured in edible portion of pacific saury from different dry methods, natural(traditional) and artificial method. ADP and AMP detected in raw fish were decrease while IMP, inosine, hypoxanthine increased during drying period. K1 values expressed as(Hx+HxR$\times$100/Hx+HxR+IMP) increased gradually throughout drying period, indicating the decline of freshness by drying. Freshness judged by change in nucleotides and related compounds was better in samples from artificial drying than from natural one. Special flavors of Kwamaegi were regarded to be synergistic actions of IMP and some amino acids. Content of total free amino acids of raw fish comprised 2.9g by weight(100g) and sum of glutamic acid, aspartic acid and histidine was over 34% of total amino acid content. Glutamic acid content. Glutamic acid, aspartic acid contents were reduced rapidly from 3rd to 9th day more decrease by artifical drying than by natural drying. Lysine content were gradually increased under two different drying conditions and threonine didn't change by two drying conditions.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.265-274
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• 2014

Physiological characteristics of two Korean golden kiwifruit cultivars, 'Halla Gold' and 'Haehyang', were compared to determine the storage potential of fruit. The soluble solid levels of the fruit were 8.9 and 6.9 oBrix in 'Halla Gold' and 'Haehyang' at harvest, respectively but increased up to 15.4 in 'Halla Gold' and 17.5 oBrix in 'Haehyang' after 2 months of storage. Major sugars were fructose and glucose, and sucrose content was relatively low regardless of cultivar. The edible quality of 'Haehyang' was better than 'Halla Gold' because of higher amount of sugars. Firmness of the fruits gradually decreased as the increase of storage period in 'Halla Gold' in both flesh and core tissue. Th firmness loss of 'Haehyang' fruit was faster in the first 2 months and then became slow. After 75 days of storage, the firmness of 'Haehyang' fruit was only 5.2% at harvest. Core tissue was soften enough to eat at ripe stage. Wall modifying enzyme activities including xylanase, ${\alpha}$-L-arabinofuranosi-dase and ${\beta}$-galactosidase were consistently higher in 'Haehyang' and the activity of pectate lyase was more increased than 'Halla Gold' after 2 months of storage. Respiration rate of 'Haehyang' was higher than 'Halla Gold' and further increased after 2 months of storage. Weight loss was much higher in 'Haehyang' which showed higher rate of the firmness loss. The storage potential of golden kiwifruit was estimated to be about 2 months for 'Haehyang' and 3 months for 'Halla Gold' when determined on the basis of the fruit firmness.