• The Korean Journal of Community Living Science
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• v.18 no.1
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• pp.55-62
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• 2007

The purpose of this study was to determine the usefulness of Shiitake mushroom, which was rich in vitamin $D_2$ through UV irradiation. For the practical use, we prepared the cold buckwheat noodles using UV irradiated Shiitake mushroom powder and seaweed derived calcium. The time required to acquire $2.5 J/cm^2$ of UV was 30-45 minutes, when the mushrooms were disposed 18 cm below within 1 cm from the UV light. Among the texture profiles detected by texture analyzer, adhesiveness and chewiness were significantly influenced by addition of mushroom powder and/or calcium. Adhesiveness appeared in only 3% mushroom powder noodle, and chewiness was significantly decreased by both of mushroom powder and seaweed calcium. Shiitake powder lowered lightness(L) and yellowness(b), but these deminishing effect on L and B value were compensated with addition of seaweed clacium. With cooking, the value of L was increased and redness(a) and yellowness(b) were decreased in comparison with raw noodle. According to sensory evaluation, addition of Shiitake and calcium increased the preference scores of color and overall acceptance of cold buckwheat noodles, but flavor, taste and texture were not influenced by those ingredients. We concluded that addition of 5% Shiitake and/or calcium to cold buckwheat noodles might give advantages for born health without bad effects on characteristics of those noodles.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.376-381
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• 1992

In order to study the effect of modified atmosphere storage on extending shelf life of mushrooms, oyster mushroom and Shiitake were wrapped with polyethylene film (PE, $50\;{\mu}m$), and stored at $0.5^{\circ}C$. Mushrooms packed with conventional hardboard box (4kg) lost marketability within $5{\sim}6$ days due to weight loss, shrinkage, browning, spore formation and/or mycellium growth. PE-packing could prevent or retard the deterioration of the mushrooms in the aspects of appearance, texture, discoloration, and microbial contamination. This situation can be best characterized by the reduced respiration rate resulted from the elevated level of carbon dioxide and the reduced level of oxygen in the bag. Although the appearance of the oyster mushroom was maintained for one month, its shelf life was limited to 15 days because of tissue softening. Discoloration of the pileus of shiitake mushroom appears to be the most important factor to determine its marketability. For example, extension of shelf life of Dongo was limited to 15 days, principally due to the browning of the pileus. Shelf life of Hawgo whose color of the pileus changed little over the experimental period, however, could be extened to more than one month.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.350-358
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• 2015

Freezing is one of the main processes to extend the shelf life of foods. Before freezing, a thermal treatment is normally required to control the food quality. In this study, shiitake mushrooms were heated with boiling water and with superheated steam. After the thermal treatments, the samples were continuously frozen by an individual quick freezing (IQF) process, and put them into air-containing or vacuum packaging. Samples were stored at -12, -18 and $-24^{\circ}C$ for 24 weeks, and their physicochemical properties were determined. The lightness of the samples treated with boiling water and superheated steam was decreased by 12 and 15%, respectively, than that of the control. The hardness of all the samples rapidly increased after heat treatment. The contents of organic acids in the superheated steam treated samples were higher than those in the boiling water treated samples. Therefore, superheated steam treatment of samples may be a candidate thermal treatment to preserve frozen shiitake mushrooms.

• 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 Mushroom
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• v.11 no.4
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• pp.201-207
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• 2013

Fungus gnats are usually found in mushroom farm and have recently become important pest because they can cause severe damage and reduce the production on shiitake mushroom. Usually shiitake mushrooms are cultivated on both oak bed logs and in the artificial sawdust beds in greenhouses. Using yellow sticky trap, the dipteran species in shiitake mushroom farm were collected from May to September in Kyonggi-do and Chungcheong-do in 2013. To identify the main species of fungus gnat on the shiitake farm in Korea, the collected samples were determined the sequence of cytochrome c oxidase subunit I (COI) by DNA barcoding. The phylogeny based on maximum likelihood analyses from COI sequence showed that Bradysia difformis and B. alpicola were main species of shiitake bed log and Scatopsidae sp. and B. difformis were dominant species of sawdust beds.

• 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.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.3
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• pp.123-129
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• 2021

Purpose: The purpose of this study was to investigate antifungal activity of shiitake mushroom yeast and hyphal type of Candida albicans. Materials and Methods: The extract from shiitake mushroom was collected by drying the supernatant after soaking shiitake mushrooms in water or ethanol. The antifungal activity of the extracts against yeast type of C. albicans was investigated by the susceptibility assay using microplate. C. albicans biofilm was formed on 12-well plate using Ham's F-12 medium in CO₂ incubator and treated with the ethanol extract. Furthermore, C. albicans biofilm was formed on denture base resin disk and treated with or without the ethanol extract in the presence of denture cleanser. Live C. albicans in biofilm was counted by cultured colony forming unit value after inoculated on agar plate. Results: Ethanol extract from shiitake mushroom showed stronger antifungal activity against yeast type of C. albicans compared to its water extract. The ethanol extract significantly reduced count of C. albicans in hyphal biofilm (P < 0.05). Also, the ethanol extract showed synergistically antifungal effect with denture cleanser on candidal biofilm on denture base resin disk (P < 0.05). Conclusion: The ethanol extract of shiitake mushroom may be a candidate for preventing candidal stomatitis as well as denture-related stomatitis.

• 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 Science and Technology
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• v.21 no.4
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• pp.461-467
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• 1989

The effect of $CO_2$ concentration on the post-harvest physiology and quality of Shiitake mushroom (Lentinus edodes) were investigated during CA storage. The respiratory rates of the mushroom stored in CA conditions were abruptly increased in proportion to $CO_2$ concentration after 40 days, and then declined, while that of the mushroom in air was continuously decreased throughout storage period. Large amounts of ethanol and acetaldehyde were produced from the 20 days CA stored mushrooms. The least changes in 5'-GMP content and electrophoresis pattern of protein in the mushroom were observed at $CO_2$ concentration of 2% during storage. Based on the changes in quality factors of the mushroom during storage, it could be concluded that $CO_2$ concentration of 2% with fixed $O_2$ concentration of 2% was more effective in extension of the freshness than any other $CO_2$ level in this experiment.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.145-148
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• 1989

Shiitake mushrooms were dried by hot air, far infrared and freeze dryers in order to compare qualities after drying. When hot air drying was performed with the four temperature variations ranged from $45\;to\;70^{\circ}C$, there was tendency to increase volume retention but decrease rehydration ratio, as drying temperature increased. And the largest amout of 5'-GMP was contained in mushroom dried at $50^{\circ}C$. For far infrared drying, volume retentions were lower but rehydration ratios were higher, as compared with hot air drying at the same temperature. In freeze drying, freezing rate had no influence on volume retention but rehydration ratio was highest value when frozen at $-18^{\circ}C$. As shelf temperature increased(drying rate increased), rehydration ratio increased. Also, contents of 5'-AMP, 5'-GMP and 5'-XMP increased with the increase of freezing rate and drying rate.