• Food Science and Preservation
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• v.4 no.3
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• pp.271-278
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• 1997

Drying of Shiitake mushroom was investigated to see the effect of temperature, relative humidity of drying air and diameter of the pileus on its rates. The drying rate was increased with the increase of the air temperature and the decrease of the relative humidity. The external color was dark brown at higher drying temperature and higher relative humidity. Exponential and Thompson nodel were found to describe well the raying process of the Shiitake mushroom.

• Journal of Biosystems Engineering
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• v.19 no.2
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• pp.112-123
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• 1994

At present, no appropriate drying conditions can be found for the heated-air drying of mushroom in Korea. Usually, mushroom is being dried at the temperature range of 40 to $50^{\circ}C$ until the moisture content reaches 10~13% (wb). However, drying characteristics of the mushroom should be investigated for quality improvement and efficient drying operation of the mushroom. The results of this study may be summarized as follows ; 1. The effect of air temperature on the rate of drying was greater than that of relative humidity for drying of mushroom, and the rate of drying was increased with increase in the air temperature. 2. Drying rate for Shiitake mushroom showed falling-rate period of drying without constant-rate period of drying. Drying rate for Oyster mushroom showed a short constant-rate period at the initial stage of drying process, and followed by falling-rate period of drying. 3. Exponential and App.-Diffusion models were found to describe well the drying process of Shiitake mushroom. Exponential and Thompson models for Oyster mushroom in which Thompson model was the most suitable for Oyster mushroom. 4. The equilibrium moisture content of the mushroom decreased with decrease in the air temperature and increase in the relative humidity. In room condition($20^{\circ}C$, 54% RH), the calculated values of the equilibrium moisture content showed 11.17% for Shiitake mushroom and 13.19% for Oyster mushroom, respectively.

• Food Science and Preservation
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• v.4 no.3
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• pp.279-286
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• 1997

The effect of drying temperature (30, 40, 50, 60$^{\circ}C$) on chemical components of Shiitake mushroom(Lentinus edodss) was investigate. When compared proximate composition on pileus and stipe of raw and dried materials, all of them were found to be higher in the stipe part than in the pileus part. The major components of organic acid were oxalic, citric, malic, malonic and pyroglutaric acid. The contents of free and total amino acids in pileus and stipe were 3458.4, 7640.2mg% for pilueus; 2298.0, 6171.5mg% for stipe on dry basis, respectively. On the other hand, there was no significant difference in the changes of crude ash and organic acids content of Shiitake mushroom among drying temperatures. But the amount of crude fats was increased and that of reducing sugars was decreased with increase of drying temperature. The contents of crude proteins of pileus part of dried materials were increased with increased drying temperature, but those of stile part were gradually decreased. The contents of free amino acids decreased with increase in drying temperature, but those of total amino acids were gradually increased.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.11 no.4
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• pp.22-27
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• 2015

Quality characteristics of Shiitake mushroom using two types of dryers, energy-efficient heat pump hot-air dryer and electric heater hot-air dryer were compared. Energy consumed during drying by heat pump hot-air dryer and electric heater hot-air dryer were 22.8 kWh and 28.9 kWh, respectively. Total polyphenol content of heat pump hot-air dryer and electric heater hot-air dryer after drying were $290.55{\pm}10.56ppm$ and $192.99{\pm}6.53ppm$, respectively. No differences were observed between dryers in reconstitution rate and browning ratio after drying. Also, there were no differences between dryers in color value and ${\Delta}E$ value after drying. Shiitake mushroom drying at $45^{\circ}C$ by heat pump hot-air dryer was proved to be more efficient in energy consumption than by electric heater hot-air dryer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.250-254
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• 2007

In an attempt to find ways of improving the quality of dried Shiitake mushroom, this study compared a conveyer-type far-infrared drying method with a traditional heated air drying method. The conveyer-type far-infrared dryer was performed at air velocity of 0.6 and 0.8 m/s under drying air temperature of 60, 70 and $80^{\circ}C$, respectively. Drying characteristics, antioxidant activities and the antioxidant compounds of Shiitake mushroom dried by far-infrared dryer were investigated. Generally, drying rate with the conveyer-type far-infrared drying method was faster than that with the traditional heated air drying method. In the conveyer type far infrared drying method, drying rates were increased with increasing temperature and air velocity. The loss of antioxidant activities during the conveyer-type far-infrared drying method at 60-0.6, 60-0.8, and $70^{\circ}C-0.6m/s$ was less than the traditional drying method. However, the loss of antioxidant activities at 70-0.8, 80-0.6, and $80^{\circ}C-0.8m/s$ was higher than that of the traditional drying method. Therefore, the conveyer type far infrared drying conditions with below $70^{\circ}C$ and 0.6 m/s air velocity may produce dried Shiitake mushroom with relatively higher antioxidant activities and antioxidant compounds.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.128-137
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• 1999

In this study, shiitake mushrooms were dried by hot air, vacuum and freeze drying methods and theire physical properties were compared. Since the pore size affects the amount of absorption, the characteristics of water sorption were investigated at various humidities and temperatures. Results showed that the freeze dried product had the greatest pore area and the highest absorption capacity. However, all the dried samples showed similar quality. The browning degrees were severely changed with increased relative humidities and temperatures. Among these drying methods, the freeze drying gave the greatest change in browning degree. The GAB monolayer moisture contents of the dried shiitake mushroom were $5.3{\sim}7.7%$. The prediction model was also provided using parameters such as relative humidity, temperature and pore area.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.419-427
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• 1985

The properties of lipids in cap and stalk of 'Koshin' (Shiitake, Lentinus edodes, withxpanded cap) were studied. It was also carried out that the characteristics of lipids in fresh 'Donko'(unexpanded cap) and the changes of lipids in those samples by various drying process. The total lipid (TL) content in the cap and stalk of 'Koshin' were 4.58% and 2.65% respectively. It was found that the contents of neutral lipids (NL, $46.7{\sim}48.8%$) and phospholipids (PL, $42.0{\sim}43.8%$) were high, while that of glycolipids(GL, $9.2{\sim}9.5%$) was low. The main lipid in NL was triacylglycerol (TG, $58.0{\sim}58.5%$) followed by sterolester (SE, $16.9{\sim}17.4%$), sterol (ST, $15.6{\sim}16.4%$), diacylglycerol (DG, $5.8{\sim}6.0%$) and monoacylglcerol (MG, $1.1{\sim}1.3%$). The main lipids in PL was phosphatidyl ethanolamine (PE, $58.3{\sim}6.02%$) followed by phosphatidyl choline (PC, $17.3{\sim}19.5%$), cardiolipin (CA, $12.8{\sim}14.0%$) and lyso-phophatidyl choline (LPD, $4.8{\sim}6.6%$). Fatty acid composition was significantly different among TL, NL, GL and PL contained in cap and stalk. The main fatty acids was $C_{18:2}$ followed by $C_{16:0}$ and $C_{18:1}$ acids. The TL contents in cap and stalk of fresh 'Donko' were 3.7% and 2.5%. The changes of TL contents, PoV by drying were not almost observed. AV(acid value) of TL in the sun dried samples was a little lower than those of the fresh and hot air dried samples, on the contrary NL content in TL of the former was a little higher than those of the latters. The main lipid in NL of the three samples was TG followed by SE, ST, DG, MG and free fatty acid (FFA). In the above lipids, FFA contents in NL of the sun dried sample was a little higher than those of the fresh and hot air dried samples, but TG content in NL of former was a little lower than those of the latters. The main lipid in GL of the three samples was digalactosydiglycerol (DGDG) followed by acylsterylglucoside(ASG), sterylglucoside (SG), monogalactosyldiglycerol (MGD) and cerebroside (CER). Influence of drying on these lipid content were nol almost recognized. The main lipid in PL of the three samples was PE followed by PC, CA, LPC and phosphat idyl serine (PS). In the above lipids, PE and PC contents in PL of the sun dried one were a little lower than those of the fresh and hot air dried ones. The main fatty acid in TL, NL, GL and PL of the three samples was $C_{18:2}$ followed by $C_{16:0},\;C_{18:1}$. The $C_{18:2}$ acid contents of the sun dried sample was a little lower than those of the fresh and hot air dried ones, while $C_{16:0}$ content of the former was a little higher than those of the former was a little lower than those of the latters.