CA1297456C - Beverage dispensing system and distributing process which includes sucha system - Google Patents

Abstract

ABSTRACT
A beverage dispensing system and distributing process with such a system has a flexible bag 1 containing the beverage which may have carbon dioxide dissolved therein. The beverage is drawn, off through a pipe 3 (assisted by a pump 8) for dispensing through nozzle 5 having a tap 6. Carbon dioxide, nitrogen (or other inert gas) and/or air gases are introduced into the beverage through a passage 11 by way of a fixed orifice restrictor 12 and a non-return valve 13.
The pressure of the gas which is introduced is adjustable at 14 and baffles 15 can provide turbulence in the beverage during dispensing to promote the dissolution of the introduced gas therein.
The facility to introduce the gas or gases permits-the-beverage in the bag 1 to have a low content of carbon dioxide so that the bag collapses under atmospheric pressure while the beverage as dispensed is additionally gasified for the formation of a froth or head.

Description

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'' TIT LE
; "A beverage dispensing system and distributing process whlch includes ~uch a system"
~ TECHNICAL FIELD AND BACKGROUND ART
; 5 Thi5 $nvention relates to a beverage dispensing system and B beverage distributing proccss which includes such a sy~tem. More partlcularly, the invention concerna such a process and system which incorporates a rlexible container charged with the beverage and which serves as a storage and transport facility and also as a source from which the beverage is withdrawn on demand. Beverage dispensing systems are well known in which a flexible container is charged with a wine, soft drink, beer or cider and fitted with a tap 30 that as the beverage is . ~-drawn off by gravity or pump and on demand through the tap, the container collapses under atmospheric pressure to maintain the '~

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beverage remaining therein substantially without headspace. It is appreciated that containers for the aforementioned systems are formed with a flexible wall structure which is impervious to the contents, precludes the beverage from the external atmosphere and has negligible, if any, adverse effect upon the characteristics of the beverage.
Generally the flexible wall structure is of plastics sheeting or metal foil or laminations thereof.
- iO A problem encountered with known dispensing sy3tems a3 aforementioned is that the beverage when dispensed has little or no gas content (either dissolved therein or liberated in the form of a froth or head on the dispensed beverage) so that the beverage as dispensed is usually regarded as "flat". For many beverages such as beer, lager, stout, cider, wine and soft drinks there is a preference by the majority of consumers that the beverage when dispensed should contain a recognisable proportion of gas, conventionally carbon dioxide. The usual consumer preference is that the beverages as aforeméntioned should have more than one volume of carbon "' ~2~745~

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dioxide gas (as measured iat 1 atmosphere and 0 C) dissolved therein for each volume of the beverage and which gas may be retained in the beverage by a pressure on the flexible container of 1 atmosphere.
~hilst it is possible to charge the flexible container with beverage having carbon dioxide gas dissolved therein and to an extent much greater than, say, one volume of carbon dioxide gas per volume of beverage, it i8 found that during transport and storage of the container with the highly gasified beverage at ambient temperature, say 16C or greater, the oarbon dloxlde gas is liberated and tends to inflate the flexible container so as to achieve an equilibrium condition in which the partial pressure of dissovled carbon dioxide gas is 1 atmosphere. This inflation will be maintained as the beverage is withdrawn from the container and the consequence is that the beverage as dispen3ed from a flexible container stored at atmospheric pressure will contain no greater volume of carbon dioxide than is achieved by equilibrium with a partial pressure Or 1 atmosphere of carbon dioxide.
It is well known physical law that the volume of carbon dioxide gas which can be dissolved in a given volume of beverage will increase as the partial pressure of carbon dioxide 1%97456 ,~

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which i9 applied to the beverage increases and decrease as the temperature o~ the beverage increases;
bearing in mind that the flexlble container is to be '~ sub~ected to atmo~pheric pressure, it can be determined from readily available tables that at 15C approximately one volume only of carbon dioxide gas oan be dissolved in one volume of beverage.
Since it frequently occurs that a beverage may be di~pensed from a flexible container in a known system as aforementioned and at a temperature in excess of 15C. lt will be appreciated for the reai30ns previously discussed, that it is difficult to provide more than say one volume o~ carbon dioxide gas per volume of beverage in the beverage dispensed from said container. Even if the beverage within the container has dissolved therein one volume of carbon dioxide gas per volume of beverage, it will be apparent that this is far less than consumer preference and it is for this reason that ... .... .. . . . .. .. . . . . . . . .. . . .. . _ .. , . . , . .............. .. . ~
known beverage dispens~ng sy3tem~ of the kind previously discussed are primarily used for beverages ~2~4S~

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which are acceptable to the consumer in a relatively un-gasified or flat condition. Flexible containers of the kind mentioned above are a convenient and : economical mean3 for the storage and transportation of beverage and there i9 a requirement for a beverage dispensing system and distributing process which includes a flexible container of the beverage that is collapsible under atmospheric pressure during dispensing of the beverage and from which the beverage can be dispensed having g~s dissolved therein to an extent greater than that available wlth existing flexible container dispensing 3ystems and without changingthe characteristics of the beverage as it is progressively dispensed from the container - it is an object of the present invention to satisfy this requirement.
STATEMENT OF INVENTION AND ADVANTAGES
~ ~ .... _ According to the present invention there i9 provided a beverage dispensing system which comprises a flexible container of the beverage, said container being subjected externally to atmospheric pressure and sealing the beverage therein from the external - ~2!3 7~S6 external atmosphere; dispensing means in sealed communication with the beveraye in ~he container for dispensing beverage from the container while the container collapses under atmospheric pressure to maintain the beverage remaining therein substantially without headspace; and means for introducing into the beverage remotely from the container and during said dispensing, at least one of carbon dioxide, nitrogen and air gases so that said introduced gas serves to provide or increase a dissolved gas content of the beverage and to form or assist in the formation of a froth or head on the beverage as dispensed, said introducing means comprising a pressurized source of the yas whlch is to be introduced, a fixed orifice restriator and a non-return valve successively through which pressurised gas from th~ source ls introduced into the beverage, and means for adjusting the pressure of the introduced gas prior to said gas passing through the restrictor.
~ lso according to the invention there is provided a beverage distributing process which comprises charging a flexible container with the beverage, said beverage upon charging being at atmospheric pressure and having carbon dioxide dissolved therein in the range of 0.6 and 1.5 volumes per volume of the beverage;
sealing the charged container; breaking said seal and couplinq the container in a dispensing system with the beverage communicating with a dispensing means; controlling the flow o~ beverage from the container for dispensing while said container collapses under atmospheric pressure over the beverage remain~ng therein to maintain said beverage substantially without headspace;
introducing into the beverage during said dispensing by way of a B

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6~ 20322-481 restrictor and a non-return valve and remo~ely from the container at least one of carbon dioxide, nitrogen and air gases so that said introduced gas or gases serve to increase the dissolved gas content of the beverage and to form or assi~'t in the formation of a froth or head on the beverage as dispensed; and adjusting the pressure of the introduced gas to proyide a required head or froth formation.
By "inert gas" as used throughout this Specification is meant a gas other than carbon dioxide with the following properties (i) it does not itself react chemically with the beverage;
~ ii) when applled to, or dis~olved in, the beverage it does not promote or develop bacteriological reactions;
(ili) it is not harmful to the consumer;
(iv) it does not impair the normal taste of the beverage.

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I, Accordingly nitrogen may be regarded as an inert gas;
an example of another inert gas which may be considered suitable for the purpose of the present invention is argon. -The system of the present invention will be located at a place of dispense for the beverage to which the flexible container of the beverage will be delivered in a sealed condition so that it wlll be a simple matter to pierce or brealc the seal and 10 couple the container into the system. The beverage within the flexible container may, for practical purposes, be considered as devoid of gas (especially carbon dioxide) dissol~ed therein so that the entire dissolved gas content may be Tv.:r~r~c~ ~raf~ff ~ f~ f~ ~f~f~fil ~f~f~f~ s~ f~

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introduced into the beverage during its dispensing from the flexible container. Alternatively however the beverage within the flexible container may have carbon dioxide gas disi~501ved therein. If present, this gas is preferably at least 0.6 volumes and less than 1.5 volumes of C2 per volume of beverage. Typically the beverage will have approximately 1.0 volumes of C02 per volume of beverage since,at the place of dispense, it is likely that the flexible container will be stored for dispensing at a temperature les~ than 15C ~so thak the carbon dioxide is unlikely to be liberated at atmospheric pressure) and consequently proportionally less gas need be introduced during the dispensing.
With fermented beverages such as beer, lager, stout and cider, the carbon dioxide dissolYed in the beverage in the flexible contàiner may result from the fermentation process. With the aforegoing in mind, there is further provided a beverage distributing process which comprises charging a flexible container with the beverage, said beverage upon charging being at atmospheric pressure and having carbon dioxide dissolved therein in the range of o.6 to 1-5 volumes per volume of the beverage; sealing the t~ r,~ r~r~ ;3~?:~/~sJ t~ y~ r~ rr:5~ r~ 5~ ?~l~it~ rr 129 7~56 9 _ ... .. . . . . . .................................. .

charged container; breaking said seal and coupling the co~tainer in the dispensing ~ystem as previously specified as being in accordance with the present invèntion and with the beverage com~unicating with 1:
the dispensing means; controlling the rlOw of beverage from the container for dispensing while said container collapses under atmospheric pressure ~ver . . ,,..... . .the.. bev.erage,.. rema,lning.,,.thereln.to.. "mainta,in"sai.d,. .. ........
beverage subst~ntlally wlthout headspace a~d lntroducing into the beverage durin~ said dispensing and remotely from the contRiner at least one of the carbon dioxide, nitrogen tor other inert gas) and air ~ases so that said introduced'ga3 or ga~es serve to increase the dissol~ed ga content of the beverage and to form or assist in the formation o~ a froth or head on the beverage as dispensed.
FDr the ma~ority o~ beers, lagers, wine~, ciders or soft drinks which may be dispensed from the lexibie container, the gas ~hich i9 introduced thereto during the di~pensing will usually be carbon dioxide derived from a storage bottle or appropriate lo-cal source which may be av~ilable on the premi~es.

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For some fermented beverages, particularly stout, the gas which iB introducs~d during the dispensing will usually be nitrogen or air (relying upon the high nitrogen content in air) - the nitrogen being derived, say, from an appropriate storage bottle or the air being derived ~rom a compressor upon demand.
Although the exposure of a fermented beverage to the oxygen content of air is normally considered detri~ental to the beverage over a prolonged period, it will be appreciated that by the present invention the air i9 only introduced on demand ard shortly before the beverage is dispensed and accordingly it ha~ been found that the exposure of the beverage to the atmospheric oxygen has negligible erfect upon the desired characteristics of the beverage. Where air or nitrogen gases are introduced to a fermented beverage as aforementioned, it is preferred that the beverage within the flexible container has carbon dioxide gas dissolved therein 90 that the beverage is dispensed with a mixed carbon dioxide and nitrogen gas content in accordance with the disclosure in our U.K. Patent Specification No. 876,628.

2~7~16 The dispensing means will usually comprise a manually adjustable valve or tap which controls the flow of beverage from the container. It i9 preferred that the adjustment of this tap also serves to control the introduction of the eas into the beverage during dispensing. The dispensing system may include a pump for withdrawal (or to assist in the withdrawal) of the beverage from the container and the operation Or this pump may also be controlled by operation of the aforementioned valve or tap.
The aforementioned control tap or valve will usually have a nozzle e~tendin~ therefrom through which the beverage is dispensed. Preferably the gas or gases are introduced into the beverage upistream Or the control tap or valve, conveniently adjacent to that tap or valve. It i8 believed important that the volume Or gas which is introduced into the beverage during dispensing can be accurately controlled to ensure that the dispensed beverage is not under or over gasified to an unacceptable level from the desired characteristics. With this in mind it is preferred that the gas is introduced ~Z917~56 ~ 11 into the beverage by way of a fixed orifice and subsequently through a non-return valve which non-return valve ensureis that the orifice ~which will necessarily be of a relatively small diameter) is not 5 contaminated by the beverage; it iis also preferred that the pressure at which the gas iis introduced into the fixed orifice is ad~ustable 90 that it can be set and maintained at a predetermined level during settin~ up of the system ~or a particular beverage and for prevalent temperature and other oonditions asi30ciated with the system. It is believed that the ; aforementioned fixed orifice and variable pressure arrangement for introducing the gas or gases to the beverage during dispensing provides an improved means of controlling the volume of the gas which i9i introduced as compared with an arrangement in which the aforementioned orifice i9 adjustable whitst the pressure of the gas directed thereto remains substantially constant. It is also preferred that the dispensing system immediately downstream of the po:ition at which the 6a: or e:ses :re introduoed ,~ i Z97~6 , ~
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into the beverage includes means, such as baffles, - ~ by which the beverage is subjected to turbulence to promote the rate at which the introduced æas or gaRes are absorbed by the beverage. The dispensing - 5 Rystem may also include small apertures or restrictors through which the beverage is dispensed downstream of the position at which the gas or gases are introduced ~particularly where the introduced gas is or comprises nitrogen) whi.ch small apertures or restrictors subJect the beverage to cavitation and assist in l~berating the dissolved gases to form or assist in the formation of a froth or head on the dispensed beverage.
The beverage dispensing system may include monitoring means ~such as a closed loop control arrangement) whereby the proportion of gas or gases in the beverage (following the introduction of the gas or gases thereto) is continuously monitored during dispensing and adjusted to ensure that the beverage is dispensed with a substantially constant and preset gas content.

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DRAWING
-One embodiment of a beverage dispensing system constructed and operated in accordance with the '~
present invention will now be described, by way of .
example only, with reference to the accompanying illustrative drawing which diagrammatically illustrates a relatively simple and inexpensive arrangement for the dispensing of a fermentPd beverage.
~ETAILED ~ESCRIPTION OF DRAWING
__ The beverage dispensing system illustrated i9 primarily intended for dispensing stout ~rom a flexible bag ~ having a plastics Yheet/metal foil or other (relatively) impermeable barrier wall . 15 structure and which is intended to collapse under : atmospheric pressure as the stout is drawn off.
; The dispensing system for~s the end of a stout distribution process which commences, usually at a brewery, with the bag 1 being charged under atmos-pheric pressure with the stout; typically the bag will be capable of holding say from 3 to 100 litres of stout. The stout which emanates from the brewery will likely have approximately 1 volume of carbon , ;

";-'` t lZ3~7~L56 3 . -dio~ide gas dissolved in it for each volume ofstout as a result of the fermentation process, and to ensure that this gas is not liberated, it is preferred that the bag is charged ~ith the stout at a temperature less than, say, 15 C. When fully charged the bag 1 is sealed so that the stout is isolated from atmospheric air and subsequently transported for connection to the dispensing system which will be located at a place of dispense, usually (but not necessarily) a retail outlet.
To facilitate handling during transpor3cation the bag will usually be supported/protected ; within a rigid or semi-rigid container.

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During transportation of the bag it is possible that some of the carbon dioxide within the stout may be liberated, for example as a result of the stout being subjected to a relatively high temperature and/or being disturbed - this may result in a small carbon dioxide headspace la being formed in the bag but this headspace should dissipate as the gas re-dissolves when the bag is left to settle in cool conditions(which usually prevail at a dispensing ~ ~ite), In the dlspenslng system the ba~ 1 may be mounted on or in an appropriate ~upport 2 a~d its seal broken by coupling to a pipe 3 through which the stout is to be dispensed. The pipe 3 can conveniently be coupled to the bag 1 by providing a tubular probe on the pipe end which breaches a diaphragm or other form of seal 4 on the bag 90 that the stout is in sealed communication with the pipe 3 and such communication is effected without the admis~ion of air. Preferably the communication between thepipe 3 and the stout is at the lowermost position of the bag 1 so that the stout w1ll flow 97~56 naturally into the pipe 3. The pipe 3 communicates with an outlet nozzle 5 having a manually operated dispensing control ~ap 6.. Provicled in the pipe , 3 upstream of the tap 6 is a gas admission inlet 7 through which it i9 intended that one or more of carbon dioxide, nitrogen (or other inert~as) or air gases may be introduced into the beverage during dispensing To assist in drawing off the beverage from the bag 1, the pipe 3 can include a pump fl which may be electrically controlled(as indioated by the line 8a) by operatlon of the tap 6 90 that the pump i9 operated only when the tap is open for dispensing purposes .
In the present example the stout is intended to be dispensed from the tap 6 having a mixture of gases, carbon dioxide and air dissolved in it - these gaies serving to provide desirable characteristics to the stout as dispensed and also to form o~ assist in the formation of a head as the ~tout is dispensed into an open topped container 9; the use of such mixed gases in the dispensing of fermented beverages is discussed in our British Patent No. 876,628.

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With this in mind, air having its high content of nitrogen is introduced by way of the inlet 7 into the stout beine dispensed and upon de~and during dispensing.
To achieve this the system includes an air compressor 10 which i~ operated through a line 10a under control of the tap 6 so that air under pressure is directed to the inlet 7 only when the tap 6 is open for dispensing purposes. Air under pressure from the compressor 10 is directed through passage 11 to the inlet 7 by w~y Or a restricted orifice 12 and subsequently by way of a non-return valve 13. The restrictor 12 has a fixed orifice and serves to reduce the air pressure prior to its introduction to the stout. The non-return valve 13 alleviates the possibility of stout flowing from the pipe 3 into and blocking the restrictor 12.
Means shown generally at 14 i9 provided for ad~usting the air pressure derived from the compressor 10 and this means provides a convenient way of setting up the system for a particular stout by which it may be ensured that a required flow rate and pressure Or air can be introduced into the stout by way of the fixed orifice restrictor 12. In a ~297~5~ ~

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typical stout dispensing system the air will be introduced to the beverage being dispensed 80 that ?
approximately 0.002 to 0.1 volumesofnitrogen gas in the air are introduced and dissolved into each volume of stout. To assist in the dissolution of the air along with the carbon dioxide gas in the stout, the pipe 3 can include baffles or other means shown generally at 15 downstream of the inlet 7 to create turbulence ln the beverage during its flow to the nozzle 5. It wil.l be noted that the air from the compressor 70 is introduced intD
the pipe 3 only on demand and immediately upstream of the tap 6 and as a consequence the relatively short period of exposure of the stout to the o~ygen in the air has not been found to have any adverse effects upon the characteristics of the stout in a practical system. Where ai.r/nitrogen gas is introduced as aforementioned, the nozzle 5 preferably includes a cavitation or restrictor plate which assists in the liberation of the dissolved gases from the stout and enhancesthe formation of the froth or head during dispensing in accordance ., "'~'.

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with conventional practice.
It will be realised that in the stout dispensing ;
system as above described, pure nitrogen can be introduced into the beverage by removing the compressor 10 and connecting the passage 11 to a bottle or other source of nitrogen gas under pressure(but again it i3 preferred that this pressure is adjustable at 14~ If the dispensing system i8 intended for use with a Plexible bag 1 containing beverage which i9 to be dispensed in a highly carbonated condition then the compressor 1D can be removed and the passage 11 coupled to a C02 ring main or bottle of carbon dioxide under pressure - preferably with the means 14 Por adjusting that pressure so that all or a proportion of the carbon dioxide can be introduced into the beverage during dispensing.
If required the system as above described can be provlded with means for monitoring the proportion of gas in the beverage as dispensed and for controll-ing and adjusting, as necessary, the gas which is introduced to the beverage to maintain the beverage as dispensed with a substantially constant and preset gas content. This may be achieved by use of .

~ i ~Z97~LS16 a closed loop control arrangement whereby a detector 16 in the pipe 3 downstream of the gas admission inlet 7 is responsive to the gas content in the beverage and is coupled (as indicated at 17) to the gas pressure adjustment means 14 to cause an ;:
adjustment, as necessary, in the gas pressure for increasing or decreasing the proportion of the introduced gas tD maintain the ga,q content as detected at 16 substantially constant at a preset level.

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Claims (15)

1. A beverage dispensing system which comprises a flexible container of the beverage, said container being subjected externally to atmospheric pressure and sealing the beverage therein from the external atmosphere; dispensing means in sealed communication with the beverage in the container for dispensing beverage from the container while the container collapses under atmospheric pressure to maintain the beverage remaining therein substantially without headspace; and means for introducing into the beverage remotely from the container and during said dispensing, at least one of carbon dioxide, nitrogen and air gases so that said introduced gas serves to provide or increase a dissolved gas content of the beverage and to form or assist in the formation of a froth or head on the beverage as dispensed, said introducing means comprising a pressurized source of the gas which is to be introduced, a fixed orifice restrictor and a non-return valve successively through which pressurised gas from the source is introduced into the beverage, and means for adjusting the pressure of the introduced gas prior to said gas passing through the restrictor.

2. A system as claimed in claim 1 in which the beverage within the container has carbon dioxide gas dissolved therein.

3. A system as claimed in claim 2 in which the carbon dioxide gas content dissolved in the beverage in the container is less than 1.5 volumes per volume of the beverage.

4. A system as claimed in claim 1 in which the beverage in the container is maintained substantially without headspace.

5. A system as claimed in claim 1 in which means is provided for subjecting the beverage and the gas or gases introduced thereto to turbulence during the dispensing of the beverage to promote the dissolution of the introduced gas in the beverage.

6. A system as claimed in claim 1 in which the gas or gases are introduced only during dispensing of the beverage.

7. A system as claimed in claim 1 in which the dispensing means comprises a pump for withdrawing beverage from the container on demand.

8. A system as claimed in claim 7 in which the dispensing means comprises a tap or valve which controls the flow of beverage during dispensing and said tap or valve controls at least one of the introduction of the gas or gases and operation of the pump during dispensing of the beverage.

9. A system as claimed in claim 1 in which the gas which is introduced is air and an air compressor is provided for effecting said introduction on demand.

10. A system as claimed in claim 1 in which the gas which is introduced comprises nitrogen, said nitrogen being dissolved in the beverage in the range of 0.002 to 0.100 volumes of nitrogen per volume of beverage.

11. A system as claimed in claim 1 in which the gas which is introduced is carbon dioxide and the carbon dioxide dissolved in the beverage following said introduction is in the range of 1.2 to 4 volumes of carbon dioxide per volume of the beverage.

12. A system as claimed in claim 1 in which the dispensing means comprises a nozzle which includes cavitation means for liberating gas or gases dissolved in the beverage to assist in the formation of said froth or head.

13. A system as claimed in claim 1 and comprising monitoring means whereby the proportion of gas in the beverage following the introduction of gas thereto is continuously monitored during dispensing and adjusted to maintain the beverage as dispensed with a substantially constant and preset gas content.

14. A system as claimed in claim 1 in which the beverage is fermented.

15. A beverage distributing process which comprises charging a flexible container with the beverage, said beverage upon charging being at atmospheric pressure and having carbon dioxide dissolved therein in the range of 0.6 and 1.5 volumes per volume of the beverage; sealing the charged container; breaking said seal and coupling the container in a dispensing system with the beverage communicating with a dispensing means; controlling the flow of beverage from the container for dispensing while said container collapses under atmospheric pressure over the beverage remaining wherein to maintain said beverage substantially without headspace; introducing into the beverage during said dispensing by way of a restrictor and a non-return valve and remotely from the container at least one of carbon dioxide, nitrogen and air gases so that said introduced gas or gases serve to increase the dissolved gas content of the beverage and to form or assist in the formation of a froth or head on the beverage as dispensed; and adjusting the pressure of the introduced gas to provide a required head or froth formation.