• Agricultural and Biosystems Engineering
• /
• v.4 no.1
• /
• pp.8-15
• /
• 2003

In Korea, quality evaluation of dried oak mushrooms are done first by classifying them into more than 10 different categories based on the state of opening of the cap, surface pattern, and colors. And mushrooms of each category are further classified into 3 or 4 groups based on its shape and size, resulting into total 30 to 40 different grades. Quality evaluation and sorting based on the external visual features are usually done manually. Since visual features of mushroom affecting quality grades are distributed over the entire surface of the mushroom, both front (cap) and back (stem and gill) surfaces should be inspected thoroughly. In fact, it is almost impossible for human to inspect every mushroom, especially when they are fed continuously via conveyor. In this paper, considering real time on-line system implementation, image processing algorithms utilizing artificial neural network have been developed for the quality grading of a mushroom. The neural network based image processing utilized the raw gray value image of fed mushrooms captured by the camera without any complex image processing such as feature enhancement and extraction to identify the feeding state and to grade the quality of a mushroom. Developed algorithms were implemented to the prototype on-line grading and sorting system. The prototype was developed to simplify the system requirement and the overall mechanism. The system was composed of automatic devices for mushroom feeding and handling, a set of computer vision system with lighting chamber, one chip microprocessor based controller, and pneumatic actuators. The proposed grading scheme was tested using the prototype. Network training for the feeding state recognition and grading was done using static images. 200 samples (20 grade levels and 10 per each grade) were used for training. 300 samples (20 grade levels and 15 per each grade) were used to validate the trained network. By changing orientation of each sample, 600 data sets were made for the test and the trained network showed around 91 % of the grading accuracy. Though image processing itself required approximately less than 0.3 second depending on a mushroom, because of the actuating device and control response, average 0.6 to 0.7 second was required for grading and sorting of a mushroom resulting into the processing capability of 5,000/hr to 6,000/hr.

• Journal of Biosystems Engineering
• /
• v.32 no.2 s.121
• /
• pp.130-135
• /
• 2007

An on-line real time grading and sorting system for dried oak mushrooms was developed for on-site application. Quality grades of the mushrooms were determined according to an industrial specification. Three dimensional visual quality features were used for the grading. A progressive color computer vision system with white LED illumination was implemented to develop an algorithm to extract external quality patterns of the dried oak mushrooms. Cap (top) and gil (stem) surface images were acquired sequentially and side image was obtained using mirror. Algorithms for extracting size, roundness, pattern and color of the cap, thickness, color of the gil and amount of rolled edge of the dried mushroom were developed. Utilizing those quality factors normal and abnormal ones were classified and normal mushrooms were further classified into 30 different grades. The sorting device was developed using microprocessor controlled electro-pneumatic system with stainless buckets. Grading accuracy was around 97% and processing time was 0.4 s in average.

• Journal of Mushroom
• /
• v.16 no.2
• /
• pp.74-78
• /
• 2018

This study was carried out to establish a suitable method for liquid spawn production from Lentinula edodes. The optimum production of liquid spawn (OLS) was achieved using soybean meal medium (SMM) with 0.3% of 850 um oak powder and 10-day incubation period and 0.6 vvm aeration volume. OLS showed activities of laccase on ABTS agar plate and carboxymethyl cellulase (CM-cellulase) on CMC agar plate. In case of liquid spawn, fruiting-body development period was delayed approximately 1 day compared to that of sawdust spawn, however, the yield of 153 g per 1.2 kg polypropylene bag was similar to that of sawdust spawn.

• Journal of Mushroom
• /
• v.20 no.3
• /
• pp.147-152
• /
• 2022

To develop mushroom varieties for cultivating at low temperature on oak logs, a strain with a low fruiting body generation temperature was crossed with Di-mon to select for a line with excellent properties. Selection was followed by cultivation testing. From these studies, Heunghwa 1ho was identified. The optimum temperature for cultivating Heunghwa 1ho, was 13.3℃. The fruiting temperature range was 6.4~20.2℃, identical to that of the parent strain. Growth at 25℃ for 7 days achieved optimal mycelial growth of 61.9±2.10 mm, superior to growth of the parent strain at this temperature. The cap shape of Heunghwa 1ho was convex, cap diameter was 57.8±8.31 mm, and cap color was brown. Heunghwa 1ho showed similar genetic traits to those of the parental strain. However, dry weight (20.1 kg/m³) and cap diameter and color are superior to those of the parent strain. The 3 year fresh oak mushroom yield was 113.8 kg/m³, superior to the respective yields of the parent strains JMI 10047 and JMI 90021 (92.5 kg/m³ and 66.4 kg/m³).

• Mycobiology
• /
• v.42 no.3
• /
• pp.279-281
• /
• 2014

Severe bark decay disease was observed on oak logs at a shiitake cultivation farm in Geochang-gun, Gyeongnam province. The symptoms observed were fruiting bodies that had developed on the top and side surface of oak logs. As a result, the bark came off easily exposing the sapwood. Slime mold specimens collected from oak logs showed developing fruiting bodies comprising of stalks, hypothallus, capillitium, and columella, and the causal agent of bark decay disease was identified as Stemonitis splendens on the basis of morphological characteristics. To our knowledge, this is the first report of Stemonitis splendens causing bark decay of oak logs used for shiitake mushroom cultivation in Korea.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.02a
• /
• pp.376-381
• /
• 2000

• The Korean Journal of Mycology
• /
• v.44 no.4
• /
• pp.289-295
• /
• 2016

Lentinula edodes is an edible wild mushroom that can be found in mountainous regions of the Korean peninsula. Wild oak mushrooms were collected from Quercus mongolica at an elevation of more than 1,000 m on Mt. Jungwang and Mt. Gariwang in Gangwon province. We examined 10 oak mushroom strains to evaluate the genetic similarity among strains. Genetic similarity was determined based on the analysis of microsatellite markers (Led A2, Led A8, Led B2, Led B6, and Led D6) registered in the National Center for Biotechnology Information. We also performed dual culture tests on potato dextrose agar for 2 months at $25^{\circ}C$. The observed heterozygosity across all microsatellites ranged from 0.00 and 0.60 among 5 microsatellite markers, and the polymorphism information content values of Led A2, Led A8, Led B2, Led B6, and Led D6 were 0.0000, 0.8144, 0.6194, 0.4892, and 0.5702, respectively (mean value = 0.4987). Confrontation lines between strains were formed for almost all combinations. In conclusion, the oak mushroom populations of Mt. Jungwang and Mt. Gariwang have mixed gene pools. However, further studies are needed to identify genetic similarities and variations among these populations.

• Journal of Mushroom
• /
• v.4 no.2
• /
• pp.62-67
• /
• 2006

Pholiota nameko is one of the four major profitable mushrooms along with oak mushroom, winter mushroom, and oyster mushroom. It contains abundant proteins, carbohydrates, organic acids and vitamins. Its unique taste and flavor as well as its nutritional features make it widely favoured. Mushroom complete medium was the optimal medium for mycelial growth of Pholiota nameko. The optimal temperature and pH for the mycelial growth were $25^{\circ}C$ and 5.0, respectively. The best carbon sources for mycelial growth were glucose and mannose, and the best nitrogen sources were yeast extract, peptone, asparagine, etc. The 8:2 ratio mix of oak sawdust and wheat bran was the best for the bottle cultivation. The best mushroom was yielded after 30 days incubation. The best yield was produced with 850g of medium weight in a PP bag and bottle.

• Journal of Mushroom
• /
• v.20 no.3
• /
• pp.183-185
• /
• 2022

High-income mushroom crops require complex farming. Therefore, we conducted a test to identify the optimum temperature for the production of antler-shaped Ganoderma lucidum using the King Oyster mushroom cultivation facility. T-N showed 0.28% of oak sawdust and 2.2% of nutritional source. The pH of oak sawdust was 6.0, indicating weak acidity, and that of rice steel was 6.6, indicating neutrality in nutrition source. Study on the quality characteristics of mushrooms showed that the number of days at 25℃ were 5~6 and those at 30℃ were 3~5; the representative length at 25℃ was 57.5 mm and that at 30℃ was 92.2 mm; the biological weight at 25 ℃ was 43 g, which was greater than that at 30℃.

• Korean Journal of Microbiology
• /
• v.51 no.3
• /
• pp.221-230
• /
• 2015

Ground bed cultivation method for shiitake mushroom (Phogo; Lentinula edodes) has been advanced to use the oak-sawdust composted by microorganisms. This method has some advantages in saving the labors and improving productivity. The aim of this study is to analyze microbial community in oak sawdust and to provide the information for efficient cultivation of shiitake mushroom. In process of composting, the proportions of thermophiles increased from 10% to 80%. This results show the microbial community succession from mesophilic bacteria to thermophilic bacteria. T-RFLP analysis and nucleotide sequencing of 16S rRNA gene demonstrated that the change of dominant bacteria coupled with shifts in each stages. The family of Enterobacteriaceae as a mesophilic bacteria were dominant (100%) in oak sawdust sample, but Amycolatopsis (49.0%) and Saccharopolyspora (26.5%) as a thermophilic Actinomycetes were dominant in the last day of composting. In hyphal growth stage, Leuconostoc (psychrophilic bacteria) was dominant (75.0%). The composting process of sawdust is very important for growth of mushroom mycelium. Therefore, there is need for the further study for the Amycolatopsis as thermophilic Actinomycetes.