• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.306-314
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• 2003

Volatile flavor components, produced during the young (P-1), immature (P-2), mature (P-3) and old (P-4) growth stages, of shiitake mushrooms (Lentinus edodes), were extracted by simultaneous steam distillation and extraction (SDE), using a mixture of n-pentane and diethyl ether (1:1, v/v) as the extraction solvent. Analyses of the concentrates, by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS), led to the identification of 129, 129, 111 and 120 components in the P-1, 2, 3 and 4 stages, respectively. The major volatile compounds were l-octen-3-o1, 3-octanol, 3-octanone and 4-octen-3-one. Ethanol and ethyl acetate were also detected in large amounts. The characteristic volatile compounds found in shiitake mushrooms, such as dimethyl disulfide, dimethyl trisulfide and 1, 2, 4-thiolane, were at low concentrations in all samples. The amount of l-octen-3-o1 decreased as growth progressed, but concentrations of 3-octanone increased. The amount of 4-octen-3-ol decreased from P-1 to P-3, but was at a high concentrations in P-4. The concentration of 3-octanol gradually increased and reached its highest concentration in P-3, but decreased in P-4. The C8-compounds comprised 70.91, 64.09, 64.29 and 60.01 % in the P-1, 2, 3 and 4 stages, respectively, so decreased gradually with growth. The S-compounds were found in the highest concentrations in P-3.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.852-859
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• 1995

Vacuum cooling were carried out for freshness keeping of shiitake mushroom. Shiitake mushroom was cooled within 30 minutes from $20.5^{\circ}C$ to $0.5^{\circ}C$ by vacuum cooling, and then temperature drop of $6.6^{\circ}C$ per weight loss of 1% was taken place during precooling. Weight loss, surface discoloration and softening were reduced by precooling. Judging from organoleptic properties such as cap opening, discoloration, texture and off-flavor, shelf-life of precooled mushroom was lengthed by 20% than that of non-treated mushrooms. Considering effect of packing material on freshness of shiitake mushroom after precooling, weight retention, hardness and organoleptic properties of mushroom packed with PVC wrap were superior to those packed in carton box.

• 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 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.

• Mycobiology
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• v.42 no.3
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• pp.301-304
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• 2014

Shiitake mushrooms (Lentinula edodes) containing ${\beta}$-glucans may be beneficial for human health; they have been used in the treatment of cancer, hypertension, and high cholesterol levels. The objective of this study was to determine the ${\beta}$-glucan content in different sections of the fruiting bodies and mycelia of ten shiitake mushroom cultivars. The measured ${\beta}$-glucan content ranged from $20.06{\pm}1.76%$ to $44.21{\pm}0.13%$ in the pileus sections, and from $29.74{\pm}1.40%$ to $56.47{\pm}4.72%$ in the stipe sections. The results of this study indicate that the variance in ${\beta}$-glucan content dependent on the shiitake cultivar, and that the ${\beta}$-glucan content is higher in the stipe than in the pileus.

• Mycobiology
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• v.49 no.2
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• pp.173-182
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• 2021

Recently, Cryptococcus pseudolongus has been reported as a new pathogen of shiitake (Lentinula edodes). However, its pathological properties are not much known. To further understand its impact on the mushroom, we investigated the pathogen's interactions with the mycelium of shiitake, histopathological properties, host range, and sensitivity to diverse antifungal agents. The strain C. pseudolongus DUCC 4014 inhibited the mycelial growth of L. edodes strain (cultivar Sanjo 701ho) and caused browning in the mycelia confronted with the yeast on PDA. Spray inoculation of the yeast caused an abnormal browning symptom on the cap and/or gills of three shiitake cultivars grown on sawdust media in vinyl bags. Scanning electron microscopic images of the abnormally browned parts of shiitake fruit body illustrated that mushroom tissues were loosed and dispersed in the middle and edge of the cap and the arrangement of basidiospores borne on basidia in the gills was disturbed compared to those of normal shiitake fruit body. Spray inoculation also led to developing abnormal browning on the harvested fruit body, indicating C. pseudolongus could be a problem during mushroom storage. But the yeast was not able to induce abnormal browning on mushrooms of Pleurotus ferulae, Pleurotus fostreatus, and Agaricus bisporus. But it induced browning only on button mushroom (A. bisporus) when they were inoculated after wounding. Tests with 16 kinds of fungicides revealed that the cell growth of C. pseudolongus could be inhibited by benzalkonium chloride at MIC 7 ㎍/ml and benomyl at MIC 3 ㎍/ml.

• Journal of Mushroom
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• v.15 no.1
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• pp.31-37
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• 2017

In this study, we investigated the amino acids content of shiitake mushrooms grown in eight different media and under three different temperature conditions. The sawdust media were supplemented with 4 kinds of nutrients - rice bran, barley, bean curd refuse, and red ginseng refuse in an 8:2 ratio with or without 0.5% calcium chloride, and the fruiting temperature was set to low ($13-15^{\circ}C$), medium ($18-20^{\circ}C$), or high temperatures ($24-26^{\circ}C$). Seventeen amino acids were detected, and the content varied depending on the compositions of the media. The highest total amino acid content (209.7 mg/g) was measured in mushrooms from the media with red ginseng refuse, and the glutamic acid content was the highest (51.3 mg/g) in mushrooms from the media with barley. In terms of fruiting temperature, the amino acid content was the highest (38.2%) at medium temperature followed by the content at low (32.5%) and high temperature (29.3%). The amino acid composition of shiitake mushrooms was similar between the medium and low temperature conditions.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.550-555
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• 1987

Strain gauges attached on the Bourdon tube and load cell were used as the sensors for measuring the vacuum pressure in drying chamber and the weight loss of Shiitake mushrooms respectively. The vacuum drying system was interfaced further with the Bear II microcomputer. The interface devices used were built with such IC chips as MC 6821, ADC 0809, SN 74244 and SN 7424. The relationship between readings of vacuum gauge (P, mmHg) and digital outputs (D) from the microcomputer was represented by P =3.08 D-13.4875(r=0.9999). The weights of drying sample (W) were also related with the digital outputs (D) by W=0.4076 D-6.4762 (r=0.9999). During the vacuum drying of Shiitake mushrooms. the data on pressure and weight were recorded at regular intervals using an acquisition program on the microcomputer system. The Page model was fitted well to the drying data of Shiitake mushrooms. resulting in the following empirical equations : $(M-M_e)/(M_o-M_e)=\exp(-0.1569t^{1.0048})$ at 400 mm Hg up to 14 hours and $(M-M_e)/(M_o-M_e)=\exp(-0.1385_t^{1.2688})$ at 600 mm Hg up to 8 hours.

• Journal of Mushroom
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• v.19 no.3
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• pp.216-224
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• 2021

This study analyzed food component characteristics and antioxidant activities in five kinds of domestic commercial shiitake mushrooms (Lentinula edodes). Moisture content (79.17-82.90 g/100 g) showed little difference, but there was a significant difference in crude protein content. Total mineral content showed a significant difference, and potassium (K) content was the highest. Total and essential amino acid contents were higher in mushroom A than in the other samples. Nonetheless, the ratios of essential amino acids, aspartic acid, and glutamic acid to total amino acids were similar in all samples. 𝛽-Glucan content was in the range of 10.28-5.68 g/100 g, exhibiting a significant difference. The color intensity and overall texture of the mushrooms showed no remarkable difference. Total phenol and flavonoid contents were in the range of 19.92-30.77 mg/100 g and 6.95-10.39 mg/100 g, respectively; the ratio of flavonoids to total phenols ranged from 31.53% to 38.21%. DPPH and ABTS radical scavenging activities were 74.92-79.04% and 80.47-84.97%, respectively, and showed little difference. However, the reducing power varied between 195.23 𝜇M and 317.85 𝜇M, displaying a significant difference in all samples. Therefore, this study observed similar trends in the food component characteristics and antioxidant activities of domestic commercial shiitake mushrooms.

• Journal of Mushroom
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• v.19 no.3
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• pp.184-190
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• 2021

With the development of sawdust medium cultivation technology, Lentinula edodes (shiitake mushroom) has become the most extensively produced and consumed mushroom globally. In this study, the approximate composition, nutritional components, and bioactive compounds of L. edodes were analyzed and compared for the five sawdust-cultivated shiitake mushrooms cultivars namely Sanjo701ho, Sanjo707ho, Sanjo715ho, Chamaram, and L808. The approximate range of the composition of freeze-dried shiitake mushrooms was 4.06-5.92 g/100 g of ash, 0.75-1.02 g/100 g of crude fat, and 21.24-29.15 g/100 g of crude protein. Sanjo701ho had the highest trehalose content (9.60±0.08 g/100 g), total polyphenol content (3.49±0.04 mg GAE/g), and total flavonoid content (1.33±0.03 mg QE/g) among the other shiitake mushroom cultivars. The total amino acid content was as follows: glutamic acid>aspartic acid>leucine. Glycine, alanine, valine, isoleucine, leucine, and phenylalanine contents were significantly decreased in the following sequence: Sanjo707ho, Sanjo715ho, Sanjo701ho, Chamaram, and L808. Crude protein, trehalose, and six types of amino acids were identified as classification indicators for the five cultivars of sawdust-cultivated shiitake mushrooms.