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The Cultivation of the Oyster Mushroom (Pleurotus Ostreatus) in Italy
443 Proc. Intl. Sym. Scientific and Technical Aspects of Cultivating Edible Fungi. The Penna. State Univ., University Park, PA, USA. July, 1986.
THE CULTIVATION OF THE OYSTER MUSHROOM (PLEUROTUS OSTREATUS) IN ITALY GIUSEPPE LANZI D i r e c t o r , Mushroom S e r v i c e and T e c h n i c a l E d i t o r , Mushroom I n f o r m a t i o n , P o g g i o r e n a t i c o , 2, M001 6 S. G i o r g i o d i Piano (BO), I t a l y
ABSTRACT Lanzi, Giuseppe. 1986. ostreatus) in Italy.
via
The cultivation of the oyster mushroom (Pleurotus
The method currently used in Italy for growing the oyster mushroom, "Pleurotus," can be considered one of the most important and well-defined methods of cultivation. Chopped and wetted straw is inoculated and held in polyethylene bags during colonization and fruiting. Colonization and fruiting occur in climatized glasshouses. Production varies from 170 to 200 Kg/ton of substrate. Fruiting occurs MO days after spawning, and the options of removing compost from the bags versus harvesting from holes in the bag are explored. 1 INTRODUCTION Annual production of Pleurotus ostreatus at commercial farms in Italy is more than 10,000 tons.
In addition, many use logs from poplar trees to grow IP.
ostreatus mushrooms for personal comsumption, and the quantity produced is difficult to determine.
Other species grown by gardeners on a smaller scale
include P_. eryngii, IP. nebro densis, and other mushrooms of the Pleurotus type. 1.1 History of Pleurotus Farming Crops were first grown in the 1960's.
The first commercial endeavors
involved the use of small-diameter logs (tree trunks) in 1969, and within a few years, compost replaced logs as the substrate. Logs were inoculated and put into a pit in the ground until the end of summer.
The white mycelium completely covered the logs by the end of summer,
when they were placed in special glasshouses.
The first mushrooms appeared in
autumn, which was the start of the harvest and sales season.
Now, the
production of Pleurotus on small logs has been abandoned except by gardeners and hobbyists.
At present the basic material used to prepare Pleurotus compost
is hard or soft wheat straw, usually without additives.Growers remain convinced by experience that the addition of other substrates is not necessary and often has negative effects on the crop.
Elsevier Science Publishers B.V., Amsterdam, 1987 - Printed in The Netherlands
444 2 CURRENT PROCEDURES 2.1 Straw Preparation The straw is worked to maximize its water retention capability.
Because it
is the extent to which the straw is crushed and ground rather than its length that enables it to retain the maximum amount of water, it is preferable to grind the straw in a hammer mill.
The hammer mill breaks and crushes the
straw, whereas blade mills only lightly cut the epidermis of the straw.
After
grinding, the straw is stacked on the fermenting wharf (batch ground in the U.S.), where it is watered constantly for a few days. straw absorbs its maximum amount of water.
During these days the
If this humidification (moistening)
process is done in piles, it is necessary to turn the straw with a front loader at least twice to achieve uniform and complete humidification for all of the straw. An alternative and less labor-intensive practice involves collecting the straw in a cement mixer as it leaves the mill and then watering it. is stacked into piles, and each pile of straw is watered. ferments e_n masse.
The straw
The moist straw
This fermentation is not necessary when preparing the
compost, but it is advantageous, because it reduces production costs.
The mass
of milled straw spontaneously reaches high temperatures, which facilitate high temperatures in the sterilization (pasteurization) tunnels. high temperatures of the mass encourage water absorption.
In addition, the
When the moisture
content of the straw exceeds 70/6, the straw is ready to be sterilized in tunnels.
As we are unaware of the microscopic flora associated with the
Pleurotus substrate (straw compost), the pasteurization process is referred to as sterilization. 2.2 Sterilization During sterilization the temperature of the compost is at 80°C for about 12 hours.
The internal temperature of the mass is estimated by monitoring the
temperature of the recycled air, which is obviously lower in temperature. To prepare the compost properly, the temperature of the mass must be the same throughout.
This is achieved by loading the compost uniformly into each
tunnel using a tunnel-loading system, which consists of a compost batcher (conveyor) on a telescopic arm.
At the end of the arm a pivoting band (ca.
140°) distributes the compost uniformly when properly managed by the operator. Each tunnel contains about 20 tons of compost. The key to sterilizing the compost is a ventilator (fan) powerful enough to allow air to permeate the mass of compost.
A large volume of air must be
present to standardize the temperatures of the compost in the tunnel throughout its width, length, and depth.
A ventilator of 4000 m3/h at 200 mm
445 of pressure (W.G.) is adequate for sterilization.
Sterilization temperatures
are obtained and maintained within the tunnel by recycling air that has been enriched with steam from a boiler.
External air needed to cool the mass after
sterilization must be filtered to avoid contaminating the sterile compost with weed molds, pathogens, or other pests.
The boiler and the steam it produces
are two necessary elements in assuring that enough heat is present to achieve sterilization. When sterilization is completed and the compost is cooled, the compost is removed from the tunnels for inoculation with spawn. 2.3 Spawning Ideally, spawning should take place in an enclosed, pressurized area where the air has been filtered.
Such spawning rooms are rarely used, unfortunately,
due to the cost of equipping and maintaining them. per ton of compost are used in Italy.
About 20 litres of spawn
The spawned compost is packed into
polythene bags, about 50 cm in diam x 90 cm tall (h). The bags are perforated to allow the compost to breathe during the incubation phase.
Currently, all
spawn incubation bags have holes, 1,5 to 2 cm diam, which allow them to be used during production with mushrooms growing directly out of the holes. of each bag is 28-30 kg.
The weight
Bags are loaded onto agricultural carts or wagons and
delivered to cultivation centers. 2.4 Mushroom Cultivation Cultivation of the Pleurotus in Italy takes place in glasshouses.
The
glasshouses are not the same as the ones used in floriculture, but are farm-glasshouses specifically designed for Pleurotus production—perfectly isolated and equipped with sophisticated air conditioning. Positioning of the compost bags in the glasshouses is very important. must be taken to assure that the bags touch as little as possible.
Care
If the bags
are too close together, air cannot circulate around the compost and monitoring temperatures becomes difficult.
Pleurotus compost tends to get hot easily, and
high temperatures kill the mushroom spawn.
It is important to monitor the
temperature of the compost a few times each day, because compost and air temperatures go hand-in-hand. The ideal air temperature during the incubation phase varies according to the species, but is always between 25 and 28°C for about 20 days.
By the end of incubation, the compost in the bags is white.
Perfect incubation results in tight compact bags of spawned compost. Following incubation, the bags are arranged into short walls in accordance with old traditions of cultivation in Italy, and the mushrooms grow on these walls.
Fresh, outside air is introduced into the glasshouses at precisely this
446 time to bring the temperature of the room to about 16°C and the temperature of the compost to about 14°C. type of spawn.
The optimum temperature varies according to the
The temperatures mentioned are for Somycel 3004 and Les Mez
306. Various growth techniques are used.
Some growers cut little windows into
the bags with a knife, and the mushrooms appear in these windows. completely remove the polyethylene bags from the compost.
Others
Generally, for the
last few years, most polyethylene bags have holes, 1.5 to 2.0 cm diam, with three rows of four holes in each side; the mushrooms grow out of these holes. Mushrooms appear about 40 days after spawning or 20 days after the compost is emptied out of the polythene bags. Which system is best?
Both systems have advantages and disadvantages.
Spawned compost removed from the bag tends to bear mushrooms abundantly on the whole surface, resulting in a quick production with a shorter cultivation cycle The mushrooms tend to remain slightly smaller in size, which may be desirable for some markets.
Climatization and humidifying systems must be sophisticated
with this system, and the mushroom grower must know the crop very well to be able to program the right environmental conditions.
Excesses of humidity,
temperature changes, and above all, dry air when mushrooms are fruiting will provoke such mortality as to invalidate the system and the economical convenience of the crop.
Conversely, perfect management of the cultivation
room will result in very high yields in a short time and more cycles each year. Advantages offered by the production of mushrooms through holes in the bags include the
protection of the substrate from environmental conditions that are
not always perfect, and the potential for abundant production of mushrooms. Another significant advantage of this method is an enormous reduction of the harvest costs:
the mushroom breaks off quickly and easily, and when the crop
is over, the bags are disposed of efficiently.
However, it is necessary that
the bags adhere to the compost; otherwise, fruit bodies develop between the bag and the compost, rather than at the holes, and will die.
Quick production is
only obtained when bags are pierced before being used; bags should not be pierced after inoculation.
Mushrooms grown on this system tend to be large,
which is preferable for many markets, and the general tendency of today's Italian cultivator is to use the system with the holes in the bag. 4 YIELD AND MARKETING Average production is about 170 Kg of mushrooms per ton of spawned compost, in Italy, although 200 Kg per ton of compost is not uncommon.
After harvest,
mushrooms are packed into wooden boxes holding 4.5 Kg each and are ready for sale.
447 5 STERILIZATION TUNNEL AND AIR CONDITIONING SYSTEM Two main features of the cultivation of Pleurotus are the sterilization tunnel and the air-conditioning system in the glasshouse. 5.1 Sterilization Tunnels The tunnels are "container" type, characterized by an interior structure appropriate for sterilization and an insulated external structure.
The
internal structure is made of steel, which allows for high sterilization temperatures.
A completely detached internal structure guarantees economic
management and avoids damages that could be suffered due to thermal expansion of the container.
The small size of the container allows easy management of
the sterilization process. 5.2 Air Conditioning The other feature necessary for successful cultivation of Pleurotus is the air-conditioning system. parts:
The climatization system consists of two fundamental
the system for monitoring climate, and the efficiency of the
conditioner.
The first monitors humidity, temperature, and the volume of air
by use of remote sensors and other electronic devices, and transmits these data to numerical displays.
The air conditioner is a strong machine that adjusts
the temperature, humidity, and ventilation and displays and records these values
on the control board.
THE CULTIVATION OF THE OYSTER MUSHROOM (PLEUROTUS OSTREATUS) IN ITALY GIUSEPPE LANZI D i r e c t o r , Mushroom S e r v i c e and T e c h n i c a l E d i t o r , Mushroom I n f o r m a t i o n , P o g g i o r e n a t i c o , 2, M001 6 S. G i o r g i o d i Piano (BO), I t a l y
ABSTRACT Lanzi, Giuseppe. 1986. ostreatus) in Italy.
via
The cultivation of the oyster mushroom (Pleurotus
The method currently used in Italy for growing the oyster mushroom, "Pleurotus," can be considered one of the most important and well-defined methods of cultivation. Chopped and wetted straw is inoculated and held in polyethylene bags during colonization and fruiting. Colonization and fruiting occur in climatized glasshouses. Production varies from 170 to 200 Kg/ton of substrate. Fruiting occurs MO days after spawning, and the options of removing compost from the bags versus harvesting from holes in the bag are explored. 1 INTRODUCTION Annual production of Pleurotus ostreatus at commercial farms in Italy is more than 10,000 tons.
In addition, many use logs from poplar trees to grow IP.
ostreatus mushrooms for personal comsumption, and the quantity produced is difficult to determine.
Other species grown by gardeners on a smaller scale
include P_. eryngii, IP. nebro densis, and other mushrooms of the Pleurotus type. 1.1 History of Pleurotus Farming Crops were first grown in the 1960's.
The first commercial endeavors
involved the use of small-diameter logs (tree trunks) in 1969, and within a few years, compost replaced logs as the substrate. Logs were inoculated and put into a pit in the ground until the end of summer.
The white mycelium completely covered the logs by the end of summer,
when they were placed in special glasshouses.
The first mushrooms appeared in
autumn, which was the start of the harvest and sales season.
Now, the
production of Pleurotus on small logs has been abandoned except by gardeners and hobbyists.
At present the basic material used to prepare Pleurotus compost
is hard or soft wheat straw, usually without additives.Growers remain convinced by experience that the addition of other substrates is not necessary and often has negative effects on the crop.
Elsevier Science Publishers B.V., Amsterdam, 1987 - Printed in The Netherlands
444 2 CURRENT PROCEDURES 2.1 Straw Preparation The straw is worked to maximize its water retention capability.
Because it
is the extent to which the straw is crushed and ground rather than its length that enables it to retain the maximum amount of water, it is preferable to grind the straw in a hammer mill.
The hammer mill breaks and crushes the
straw, whereas blade mills only lightly cut the epidermis of the straw.
After
grinding, the straw is stacked on the fermenting wharf (batch ground in the U.S.), where it is watered constantly for a few days. straw absorbs its maximum amount of water.
During these days the
If this humidification (moistening)
process is done in piles, it is necessary to turn the straw with a front loader at least twice to achieve uniform and complete humidification for all of the straw. An alternative and less labor-intensive practice involves collecting the straw in a cement mixer as it leaves the mill and then watering it. is stacked into piles, and each pile of straw is watered. ferments e_n masse.
The straw
The moist straw
This fermentation is not necessary when preparing the
compost, but it is advantageous, because it reduces production costs.
The mass
of milled straw spontaneously reaches high temperatures, which facilitate high temperatures in the sterilization (pasteurization) tunnels. high temperatures of the mass encourage water absorption.
In addition, the
When the moisture
content of the straw exceeds 70/6, the straw is ready to be sterilized in tunnels.
As we are unaware of the microscopic flora associated with the
Pleurotus substrate (straw compost), the pasteurization process is referred to as sterilization. 2.2 Sterilization During sterilization the temperature of the compost is at 80°C for about 12 hours.
The internal temperature of the mass is estimated by monitoring the
temperature of the recycled air, which is obviously lower in temperature. To prepare the compost properly, the temperature of the mass must be the same throughout.
This is achieved by loading the compost uniformly into each
tunnel using a tunnel-loading system, which consists of a compost batcher (conveyor) on a telescopic arm.
At the end of the arm a pivoting band (ca.
140°) distributes the compost uniformly when properly managed by the operator. Each tunnel contains about 20 tons of compost. The key to sterilizing the compost is a ventilator (fan) powerful enough to allow air to permeate the mass of compost.
A large volume of air must be
present to standardize the temperatures of the compost in the tunnel throughout its width, length, and depth.
A ventilator of 4000 m3/h at 200 mm
445 of pressure (W.G.) is adequate for sterilization.
Sterilization temperatures
are obtained and maintained within the tunnel by recycling air that has been enriched with steam from a boiler.
External air needed to cool the mass after
sterilization must be filtered to avoid contaminating the sterile compost with weed molds, pathogens, or other pests.
The boiler and the steam it produces
are two necessary elements in assuring that enough heat is present to achieve sterilization. When sterilization is completed and the compost is cooled, the compost is removed from the tunnels for inoculation with spawn. 2.3 Spawning Ideally, spawning should take place in an enclosed, pressurized area where the air has been filtered.
Such spawning rooms are rarely used, unfortunately,
due to the cost of equipping and maintaining them. per ton of compost are used in Italy.
About 20 litres of spawn
The spawned compost is packed into
polythene bags, about 50 cm in diam x 90 cm tall (h). The bags are perforated to allow the compost to breathe during the incubation phase.
Currently, all
spawn incubation bags have holes, 1,5 to 2 cm diam, which allow them to be used during production with mushrooms growing directly out of the holes. of each bag is 28-30 kg.
The weight
Bags are loaded onto agricultural carts or wagons and
delivered to cultivation centers. 2.4 Mushroom Cultivation Cultivation of the Pleurotus in Italy takes place in glasshouses.
The
glasshouses are not the same as the ones used in floriculture, but are farm-glasshouses specifically designed for Pleurotus production—perfectly isolated and equipped with sophisticated air conditioning. Positioning of the compost bags in the glasshouses is very important. must be taken to assure that the bags touch as little as possible.
Care
If the bags
are too close together, air cannot circulate around the compost and monitoring temperatures becomes difficult.
Pleurotus compost tends to get hot easily, and
high temperatures kill the mushroom spawn.
It is important to monitor the
temperature of the compost a few times each day, because compost and air temperatures go hand-in-hand. The ideal air temperature during the incubation phase varies according to the species, but is always between 25 and 28°C for about 20 days.
By the end of incubation, the compost in the bags is white.
Perfect incubation results in tight compact bags of spawned compost. Following incubation, the bags are arranged into short walls in accordance with old traditions of cultivation in Italy, and the mushrooms grow on these walls.
Fresh, outside air is introduced into the glasshouses at precisely this
446 time to bring the temperature of the room to about 16°C and the temperature of the compost to about 14°C. type of spawn.
The optimum temperature varies according to the
The temperatures mentioned are for Somycel 3004 and Les Mez
306. Various growth techniques are used.
Some growers cut little windows into
the bags with a knife, and the mushrooms appear in these windows. completely remove the polyethylene bags from the compost.
Others
Generally, for the
last few years, most polyethylene bags have holes, 1.5 to 2.0 cm diam, with three rows of four holes in each side; the mushrooms grow out of these holes. Mushrooms appear about 40 days after spawning or 20 days after the compost is emptied out of the polythene bags. Which system is best?
Both systems have advantages and disadvantages.
Spawned compost removed from the bag tends to bear mushrooms abundantly on the whole surface, resulting in a quick production with a shorter cultivation cycle The mushrooms tend to remain slightly smaller in size, which may be desirable for some markets.
Climatization and humidifying systems must be sophisticated
with this system, and the mushroom grower must know the crop very well to be able to program the right environmental conditions.
Excesses of humidity,
temperature changes, and above all, dry air when mushrooms are fruiting will provoke such mortality as to invalidate the system and the economical convenience of the crop.
Conversely, perfect management of the cultivation
room will result in very high yields in a short time and more cycles each year. Advantages offered by the production of mushrooms through holes in the bags include the
protection of the substrate from environmental conditions that are
not always perfect, and the potential for abundant production of mushrooms. Another significant advantage of this method is an enormous reduction of the harvest costs:
the mushroom breaks off quickly and easily, and when the crop
is over, the bags are disposed of efficiently.
However, it is necessary that
the bags adhere to the compost; otherwise, fruit bodies develop between the bag and the compost, rather than at the holes, and will die.
Quick production is
only obtained when bags are pierced before being used; bags should not be pierced after inoculation.
Mushrooms grown on this system tend to be large,
which is preferable for many markets, and the general tendency of today's Italian cultivator is to use the system with the holes in the bag. 4 YIELD AND MARKETING Average production is about 170 Kg of mushrooms per ton of spawned compost, in Italy, although 200 Kg per ton of compost is not uncommon.
After harvest,
mushrooms are packed into wooden boxes holding 4.5 Kg each and are ready for sale.
447 5 STERILIZATION TUNNEL AND AIR CONDITIONING SYSTEM Two main features of the cultivation of Pleurotus are the sterilization tunnel and the air-conditioning system in the glasshouse. 5.1 Sterilization Tunnels The tunnels are "container" type, characterized by an interior structure appropriate for sterilization and an insulated external structure.
The
internal structure is made of steel, which allows for high sterilization temperatures.
A completely detached internal structure guarantees economic
management and avoids damages that could be suffered due to thermal expansion of the container.
The small size of the container allows easy management of
the sterilization process. 5.2 Air Conditioning The other feature necessary for successful cultivation of Pleurotus is the air-conditioning system. parts:
The climatization system consists of two fundamental
the system for monitoring climate, and the efficiency of the
conditioner.
The first monitors humidity, temperature, and the volume of air
by use of remote sensors and other electronic devices, and transmits these data to numerical displays.
The air conditioner is a strong machine that adjusts
the temperature, humidity, and ventilation and displays and records these values
on the control board.