WO2004111181A1

WO2004111181A1 - A plant for solid state fermentation

Info

Publication number: WO2004111181A1
Application number: PCT/IB2004/001932
Authority: WO
Inventors: Giuseppe Bobbiesi
Original assignee: Elep S.A.S. Di Cabiddu Rachele & C.
Priority date: 2003-06-13
Filing date: 2004-06-11
Publication date: 2004-12-23
Also published as: ITMI20031191A1; ITMI20031191A0; EP1633848A1

Abstract

The object of the invention is a Solid State Fermentation plant for the production of biomass and/or metabolites which plant consists in a number of transparent plastic bags divided into two chambers by an horizontal baffle, the lower chamber being provided with an air sterilizing filter and the upper chamber being provided with a metallic nozzle with a porous sterilizing plug, a number of bag scaffoldings, and an air low pressure supply and distribution system and a growth medium preparation equipment.

Description

A Plant for Solid State Fermentation

Brief description of the invention

The object of the invention relates to a Solid State

Fermentation plant for the production of biomass and/or

metabolites, which shows interesting characteristics as to its

design, implementation and costs are concerned.

Background of the invention

The Solid State Fermentation (SSF) involves the microorganism

growth of different genera, mainly fungi, on humid substrates;

this kind of process has a considerable economic strength for

the production of products in the agro-food and pharmaceutical

industries. Some typical applications of the SSF include

bakery and oven product production, fermented foods, cheeses

and starters for the beer, sausage and compost industry.

The SSF most recent applications include the protein

enrichment of the agro-food residues, the production of

enzymes, organic acids, metabolites and fungi spores. SSF

presents several advantages versus the submerged fermentation

due to its higher substrate concentration, process energy

saving and technology simplicity.

The two SSF main techniques foresee the culture of

microorganisms on a substrate formed by cereals, such as corn,

rice, barley, etc. or on a substrate of a suitable liquid

growth medium absorbed on inert. Description of the invention

The object of the present invention is a Solid State

Fermentation (SSF) plant which presents interesting

characteristics due to its simple design, implementation and

cost saving.

In particular, the SSF plant of the invention is formed by a

suitable number of transparent plastic bags, scaffoldings, an

air treatment and distribution system and a growth medium

preparation equipment. The plant is also provided with an

usual instrumentation system for the automatic control and

record of all the plant operation parameters (temperature,

pressure, air humidity and flow-rate and safety) .

More specifically, the plastic bag of the plant of the present

invention is made of a suitable transparent plastic material

and is internally, longitudinally divided by a sheet, made of

the same plastic material as the bag, into an upper chamber

and a lower chamber. The longitudinal sheet crossing the bag

has a central porous or micro-perforated zone, which may also

be called porous or micro-perforated baffle.

on the external wall of the bag lower chamber is fixed an air

sterilizing filter which allows the sterilized air to flow

under the porous or micro-perforated baffle. On the external

wall of the bag upper chamber is fixed a metallic nozzle

having a diameter from 1 to 20cm, preferably from 5 to 6cm. During the fermentation, the metallic nozzle is closed by an

air sterilizing porous plug which allows the air and the

fermentation gases to be discharged from the upper chamber or

to take samples of the growth fermented substrate or to allow

the flame sterile inoculation. Said nozzle is plugged by a

removable filtering and sterilizing plug for microbiology. The

bag is filled with the growth medium in the upper chamber,

over the porous or micro-perforated baffle, ready to be sent

to the sterilization performed by non thermal technologies.

The transparent plastic material, the plant bag is made with,

makes possible a visual control of the fermenting mass from

the outside, characteristic which renders easier to the plant

operator the control of the development of the fermentation

process .

A convenient bag size ranges from about 50x20cm to about

200xl00cm.

The rack for supporting the transparent plastic bag is formed

by a normal scaffolding having shelves of the same size as the

bag and being the vertical distance between each other ranging

from 15 to 80cm, preferably 40cm. The rack is suitable for the

installation of pipes and air distributors.

The air supply and distribution system is formed by a blower,

having a pre-filter on the suction and by an air conditioning

system providing a_, flow-rate of from 0.05 to 5L/min per kilogram of the growth medium, preferably Q.2÷0.8L/min per

kilogram of the growth medium, at a suitable pressure,

preferably from 5-30mbar, more preferably 15÷20mbar.

The system can provide two different types of air: one for the

dry air and one for the humid air.

The air from the blower or from the air treatment flows to two

separate general distribution pipe systems; for dry air and

for humid air. Therefrom minor pipes derive, which may be shut

off by valves (generally one or two for every rack) , from

which pipes derive which are shut off by valves or pliers for

every shelf and therefore for every bag. These last pipes are

connected to the bag filters at the time these are placed on

the shelves to start the fermentation process .

The growth medium preparation equipment is formed by a

jacketed vessel with cover and by a strong, slow mixer, which

can be lifted to allow complete access to the vessel with the

possibility of steam injecting into the substrate mass and

jacket heating while the mixer is on. The preferred growth

medium preparation vessel has the geometrical capacity from

about 0.5 to Im³, a mixer power of 15-20Hp, a hydraulic lifter

of the mixer, so as to leave the vessel totally free and over-

turnable . Depending from the quantity of the growth medium to be

cultivated one or more transparent plastic bag may be used

and, consequently, may vary the number of scaffoldings used.

The attached drawings are given for better illustrating the

plant of the invention.

Figure 1 represents a perspective view of the transparent

plastic bag of the plant of the invention;

Figure 2 represents a frontal view of the bag of Figure 1

according to the direction of arrow A;

Figure 3 represents the air supplying and distribution system

to the bags of Figure 1;

Figure 4 represents a sketch of the growth medium preparation

of the plant of the invention.

In the above mentioned Figures are shown the components of the

plant which are: the transparent plastic bag (1) divided by a

porous or a micro-perforated baffle (2) into two parts, the

upper chamber (3) and the lower chamber (4), the metallic

nozzles (5) with the air sterilizing porous plug (6) on the

external wall of the upper chamber (3), the air sterilizing

filter (7) on the external wall of the lower chamber (4),

being the metallic nozzle (5) and the sterilizing filter (7)

located in a diagonally opposite position as per in Figure 1;

the dry air line (8), the humid air line (9), the tube/s (10)

connecting the dry air line (8) and the tube/s (11) connecting the humid air line (9) to the bag or to the bags (1), being

the tubes (10) and (11) preferably made of rubber, various

racks (12) , (13) , (14) and (15), a bag support (16), the growth

medium preparation equipment (17) composed by the jacketed

vessel (18), the mixer (19) and the hydraulic mixer lifter

device (20) .

The growth medium is prepared in the jacketed vessel (18) of

the growth medium preparation equipment (17) while the stirrer

(19) is on and steam injection is provided and then

transferred into the bag (1) over the porous or micro-

perforated baffle (2) where it is indicated by the reference

number (21) in Figure 2. Dry or humid air is supplied through

the pipes (8) and (9), and the rubber tubes (10) and (11) to

the plastic bag (1) through the sterilizing filter (7) . The

air and fermentation gases flow to the atmosphere through the

nozzle (5) provided with the porous sterilizing plug (6) .

The air supply and distribution system is provided by an

appropriate number of valves (22) in order to send, even

contemporarily, dry and humid air to different bags.

Claims

1. A Solid State Fermentation plant for growing microorganisms of different genera, characterized by the fact that it consists of the following main components: a number of

⁵ bags of transparent plastic material (1) , each bag being divided, in a longitudinal way, into an upper (3) and a lower chamber (4) by a transparent plastic sheet (2) having a central zone suitable for the air to pass through it, being the bag upper chamber (3) provided, on its external wall, with ° a metallic nozzle (5) having a filtering, sterilizing plug (6); and the bag lower chamber (4) provided, on its external wall; with a sterilizing filter (7) ; a number of bag. scaffoldings; a low pressure air supply and distribution system (23) having <a dry line (8) and a humid line (9), which may be. suitably 5 connected by means of the tubes (10) and (11) .to -the.,:.bag through the sterilizing filter (7) on the lower _^'chamber ■ (4),

and a growth medium preparation equipment (17) consisting of: a jacketed vessel (18), suitably provided with means for steam injection into the medium while the mixer is on, with a strong, low stirrer (19) and a hydraulic mixer lifter (20)-.

2. The Solid State Fermentation plant according to claim 1, wherein the central zone of the longitudinal transparent plastic sheet (2) is porous. ' ^■ i ■

3. The Solid State Fermentation plant according to claim 1,

wherein the central zone of the longitudinal transparent

plastic sheet (2) is micro-perforated.

4. The Solid State Fermentation plant according to claims 1

to 3, wherein the air is supplied at the pressure of from 5 to

30mbar.

5. The Solid State Fermentation plant according to claims 1

to 4, wherein the air is supplied at the pressure of lSmbar.

6. A bag suitable for Solid State Fermentation, characterized

by the fact that it is made of transparent plastic material,

and is divided, in a longitudinal way, into an upper (3) and a

lower chamber (4) by a transparent plastic sheet (2) having a

central zone suitable for the air to pass through it, being

the bag upper chamber (3) provided, on its external wall, with

a metallic nozzle (5) having a filtering, sterilizing plug (6)

and the bag lower chamber (4) provided, on its external wall,

with a sterilizing filter (7) .