• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.39-44
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• 2004

This study was carried out to investigate the tenderizing effect of Neungi mushroom (Sarcodon aspratus) powder and its protease. The addition of Neungi mushroom powder and its protease enhanced water retention values (WRY) of meat. The WRY of meat was increased 26.8% by protease addition, compared to 13.8% WRV by sugar addition. This increase in WRY derived to the increase of water soluble fraction in the meat texture by hydrolysis of meat protein, and had the meat tenderized. Concerned to the meat tenderizing effect, the addition of Neungi mushroom powder and its protease have decreased of meat hardness and gave similar tenderizing effect, as compared to commercial tenderizer, papain. The decreasing rates of meat hardness were 51.6% of Neungi mushroom powder, 58.5% of its protease, and 563% of commercial tenderizer, papain. This tenderizing effect of protease attributed to the degradation of muscle fiber protein in meat, such as actin, myosin and connectin etc. The addition of Neungi mushroom to foods gives significant changes in food color, mainly decreasing lightness.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.58-65
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• 2004

This study was performed to investigate the protease activity from fruit body of Sarcodon aspratus and its features. The specific protease activity was increased with the increasing purification steps, 2.62 times by desalting, 17 times by CMC column chromatography, 113.8 times by DEAE-Sephadex A-50 column chromatography, and 728.3 times by Sephadex G-75 column chromatography. Proteases were identified as two different enzymes having different isoelectric points at pH 4.35 (its recovery rate 8%) and pH 4.7 (its recovery rate 3.5%). Those proteases were purified by 3,025 folds and 3,257 folds in terms of specific activity. Two proteases having different isoelectric points had similar enzymatic properties. This protease was estimated to be 43,000 daltons of molecular weights by SDS-PAGE. This protease with optimum pH 4 was almost stable in the pH range of 4~7. Optimal temperature of protease activity was 40 to 50℃, and the protease activity was completely inhibited at 70℃ for 30 min.