• Journal of Mushroom
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• v.21 no.4
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• pp.200-208
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• 2023

This study was conducted to investigate the reasons for the decreased importation of fresh Shiitake mushrooms into Korea after implementation of the Korea-China Free Trade Agreement (FTA). Monthly time-series data from January 2009 to December 2022 were analyzed using regression analysis and vector autoregression (VAR) models to determine the relationship between the amounts of fresh and spawn Shiitake mushrooms imported. The analysis revealed that a major reason for the decreased importation of fresh Shiitake mushrooms was an increase in mushroom spawn imports after Korea-China FTA implementation. The same results were obtained from the VAR model analysis. However, in terms of the dynamic changes in amount of fresh shiitake mushrooms imported, it was confirmed that the impact of the change in mushroom spawn imports could increase the amount of Shiitake mushrooms imported.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.197-202
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• 2013

This study was aimed to find the storage potential of low temperature adapted shiitake mushroom under freezing temperature ($-3^{\circ}C$). Fresh shiitake mushroom was harvested at late Feb. and cooled to target temperature, $-3^{\circ}C$ in the cooling room for 24 hr. Cooled mushroom were then placed in plastic boxes, wrapped with plastic film ($30{\mu}m$), and stored at $-3^{\circ}C$ for 2 months. Weight loss of mushroom was ranged from 2.1 to 3.2%. Dry weight per unit fresh weight, however, was slightly increased because of moisture loss. Firmness of fruit body increased from $0.95kg/cm^{-2}$ (before storage) to $1.13kg/cm^{-2}$ (after 2 month storage). About half amount of starch was lost during 2 month storage. The amount of total and reducing sugars remained relatively constant. After storage, freshness of mushroom was recovered by thawing treatment. When recovered mushroom were packaged with styrofoam tray and PVC wrapping, and exposed to ambient and $10^{\circ}C$, respectively, brown spot on the gill of fruit body was found and slight decay symptom was also found at ambient temperature only but not at $10^{\circ}C$. Results indicated that low temperature adapted shiitake mushroom has a storage potential under freezing temperature ($-3^{\circ}C$). Freezing storage technology of fresh shiitake mushroom will contribute the increase of storability up to 2 months.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.606-612
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• 1988

The volatile flavor compounds of fresh and dried shiitake mushrooms(Lentinus edodes) were extracted by simultaneous steam distillation-extraction apparatus, and analyzed by combined GC and GC-MS, and effects of pH on the formation of volatile compounds in fresh shiitake mushroom were investigated. Of the 29 compounds identified from fresh shiitake mushroom, the main volatile compound was 1-octen-3-ol comprising about 74.7% of the total volatiles and that in dried shiitake mushroom was 1, 2, 4-trithiolane comprising about 66.3%. With the exception of above two compounds, 3-octanone, 1-octen-3-one, 3-octanol, cis-2-octenal, n-octanol and cis-2-octenol as $C_8$ compounds were identified. Carbon disulfide, dimethyl disulfide, dimethyl trisulfide, 1-(methyl thio)-dimethyl disulfide, 1, 2, 4, 5-tetrathiane as sulfurous compounds were also identified. The formation of $C_8$ compounds in fresh shiitake mushroom during immersion was dominant in the range of pH 6.0 to 7.0, while the formation of sulfurous compounds in the range of pH 8.0 to 9.0.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.20 no.3
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• pp.71-76
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• 2014

Master packaging system is a technology combining primary and secondary packaging to preserve the fresh produce in the supply chain. Master packaging system with tailor-designed gas transfer and $CO_2$ absorber of $Ca(OH)_2$ was applied to fresh shiitake mushroom in its supply from farm to retail store. The temperature, humidity and package atmosphere were monitored through the distribution and/or storage until the packages were opened to measure the mushroom quality. Conventional perforated individual packages without secondary master pack were prepared and travelled the same path for comparison purpose. While high temperature history was observed in some initial period of actual practice of the mushroom transportation and storage unexpectedly, the package atmosphere around the produce in the master packaging system was maintained at modified atmosphere consisting of $O_2$ concentration of 0.4 to 4.2% and $CO_2$ concentration of 0.7 to 1.7%, which is known to be beneficial for the mushroom preservation. While curing the mushrooms with precooled drying was effective for quality preservation, positive effect of master packaging system could be apparent for the uncured mushroom. Harmonized combination of curing treatment, master packaging system and temperature management was suggested for the best quality preservation of the fresh shiitake mushroom.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.423-432
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• 1993

The changes of quality of Fresh Shiitake (Lentinus edodes) was studied in this research work by investigating the effect of low $O_2$ content and high $CO_2$ content, well known as CA Treatment in storage, on the respiration rate and PPO Activity that was the main factor in Shiitake quality decay. CA Condition was conducted in 3 research periods that combined the $O_2$content(1%, 5% and 10%) and $CO_2$ content (5%, 10%, 15% and 20%) and air treatment as the control. The lower $O_2$content was the lower respiration rte that was showed in combination the lower respiration rate that was showed in combination of 20% $CO_2$ and 1% $O_2$ (the lowest), and the control air treatment was the highest . Very low $O_2$ content, conversly, did not show a satisfying result to the product.

• Food Science and Preservation
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• v.24 no.3
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• pp.381-386
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• 2017

Ergocalciferol is known as having vitamin D activity. In this study, the effects of UV irradiation on the increase of egocalciferol content were investigated in 7 kinds of mushrooms, i.e, lily mushroom (Flammulina velutipes), oyster mushroom (Pleurotus ostreatus), young oyster mushroom (Pleurotus ostreatus), king oyster mushroom (Pleurotus eryngii), button mushroom (Agaricus bisporus), shiitake (Lentinula edodes), and wood ear mushroom (Auricularia auricula-judae). Mushrooms which were not exposed to UV light contained negligible amount of ergocalciferol in all kinds of tested mushrooms, but UV irradiation increased their content of ergocalciferol. Of UV A, B and C, UV B light was the most effective to increase ergocalciferol contents. In mushrooms, the increase in ergocalciferol content occurred only in the peel within 1 mm depth from the surface, which was directly exposed to the UV light. Therefore, when fresh whole mushrooms were irradiated with UV light, lily mushroom, the mushroom with a larger surface area compared to volume, such as lily mushroom, was more favorable in producing ergocalciferol. On the other hand when the mushrooms were freeze-dried and cut, the mushrooms with a higher ergosterol, such as king oyster mushroom, shiitake or button mushroom, were more favorable in generating ergocalciferol.

• Journal of Mushroom
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• v.15 no.4
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• pp.164-167
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• 2017

Biological efficiency (BE), the ratio of fresh mushrooms harvested per dry substrate weight, expressed as the percentage of Lentinula edodes, also known as shiitake, was determined using the 'Sanjo 701' strain stored in the Department of Mushroom at the Korea National College of Agriculture and Fisheries. The mycelia were grown in glass columns with varying levels of moisture content and varying mixing periods of 0.5, 1, 2, and 3 hours. The substrate was sterilized using a steam pressure autoclave sterilizer at normal and high pressure to avoid contamination. The results showed that mycelial growth (126 mm/15 days) was optimized at 55% moisture content. The best mycelial growth of 117 mm/15 days was obtained with 2 hours of mixing time. Normal pressure sterilization yielded better results with mycelial growth of 96 mm/15 days at $100^{\circ}C$ compared to 88 mm /15 days with sterilization at $121^{\circ}C$. Mycelial density was higher, i.e. 3(+++), with normal pressure sterilization compared to 2(++) with high pressure sterilization. Furthermore, sawdust mixed with 5% woodchips increased the substrate porosity and yielded higher mycelial growth. Thus, we demonstrated that the optimum harvest or potential increased yield of shiitake can be obtained by modulating moisture content, mixing time, and substrate porosity.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.173-178
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• 2002

Fresh Shiitake mushrooms were irradiated by UV-B or dried by using hot air to increase the vitamin D$_2$content. Vitamin D$_2$content was determined by high-performance liquid chromatography Irradiating the inside of the mushroom cap was more effective in increasing vitamin D$_2$content than irradiating the outside of the mushroom cap. Irradiation of UV-B at 0, 2.5, 5.0, 7.5 and 10 J/㎠ increased the content of vitamin D$_2$in the mushroom to 21.51, 120.78, 144.38, 168.08, and 187.69 $\mu\textrm{g}$/g, respectively. Vitamin D$_2$content of Shiitake mushrooms with irradiation of 10 J/㎠ decreased from 187.69 to 98.78 $\mu\textrm{g}$/g by 6 hours of hot-air drying. When three kinds of drying method (UV-B irradiation followed by hot-air drying, hot-air drying, and sunlight drying) were compared, the combination of UV-B irradiation and hot-air drying was the most effective in terms of increasine the vitamin D$_2$content in the mushroom.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.402-408
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• 2016

Master packaging system consists of an inner individual package and secondary outer package. During the stages of chilled transport and distribution, the combination of primary individual package and secondary package was used to maintain a modified atmosphere for shiitake mushrooms. During the retail stage at higher temperature ($25^{\circ}C$), the primary individual package was exposed to display conditions after dismantling of the secondary packaging. The master packaging system was constructed to contain eight individual $30-{\mu}m$ thick polypropylene film bags of 500 g shiitake mushrooms inside a $40-{\mu}m$ low-density polyethylene bag. Carbon dioxide absorbent material [$Ca(OH)_2$] and/or moisture absorbent (superabsorbent polymer) were designed in their required amounts based on respiration characteristics and then applied to the outer secondary packaging in sachet form. Gas concentration of the packaging, temperature, and humidity were monitored throughout transport and storage. The quality of shiitake mushrooms was measured at the retail stage to determine the packaging effect. During the distribution stage of 108 h, $O_2$ and $CO_2$ concentrations in the master packaging system were maintained at 9~11% and 1~4% in the inner packaging, respectively, which are good for quality preservation. Compared to the control, the master packaging with $CO_2$ and/or moisture absorbents improved mushroom preservation and particularly reduced decay.

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.79-88
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• 2001

Lectin was isolated from shiitake mushroom (Lentinula edodes) with 0.15 M NaCl solution, and purified by the following procedures : precipitation by ammonium sulfate, anion exchange column chromatography on DEAE Sephadex A-50 and hydroxyapatite column chromatography. The fresh pileus part of the mushroom contained more than two times of lectin compared to the stipe part, and lectins and its activity were reduced by heating. The extraction yield of crude lectin was 46.03%, 28% yield after purification on on DEAE Sephadex A-50 column chromatography. Some amino acids, aspartic acid, serine, alanine and histidine, were increased by purification process. Relatively low molecular weight parts of lectin had the agglutinating activity for rabbit blood, and its molecular weight was about 23 kDa The molecular weights of purified lectins, LA-a and LB-b, by the hydroxyapatite column chromatography were 24 kDa and 23 kDa, respectively.