WO2018172913A1

WO2018172913A1 - Transparent keg for liquid foods

Info

Publication number: WO2018172913A1
Application number: PCT/IB2018/051826
Authority: WO
Inventors: Andrea MORATTI
Original assignee: Keg Solutions S.R.L.
Priority date: 2017-03-20
Filing date: 2018-03-19
Publication date: 2018-09-27
Also published as: IT201700030293A1

Abstract

A keg (1) for liquid foods, for example for beer, comprises an outer container (3), a deformable bag (2) capable of receiving therein a liquid food (L) housed inside the outer container (3) and valve means (4) for filling and emptying the bag (2). The keg is characterized by the fact that the inner bag (2) and the outer container (3) are made of transparent or semi- transparent polymeric material, and the inner bag (2) and/or the outer container (3) are made of polymeric material loaded with a UV radiation-absorbing additive. Such transparent keg allows the filling of the inner bag to be monitored visually, avoiding any exposure to light and the so-called "lightstruck flavor".

Description

DESCRIPTION

" TRANSPARENT KEG FOR LIQUID FOODS"

[0001] The object of the present invention is a disposable keg for liquid foods.

[0002] The present invention is generally applicable to the technical field of beverage distribution systems, in particular for beer, wine and soft drinks.

[0003] In this technical field, it is essential to ensure that the organoleptic properties of the food product are maintained, and therefore to ensure the product is protected from light and oxygen.

[0004] With particular reference to beer, well known and feared in the field is the so-called "lightstruck flavor" or "skunky beer", an unpleasant, bad smell caused by the isomerization of iso- -acids (contained in hops and responsible for the bitterness of beer) and small mercaptans (including hydrogen sulfide H₂S), which, in the presence of artificial or natural light, lead to the formation of 3-methyl-2-buten-l-thiol , a substance that contains sulfur and generates an annoying bad smell. Precisely for this reason, mainly steel kegs are used for beer storage.

[0005] For logistical reasons and cost containment, the field is also experiencing a strong development of "disposable" plastic kegs, consisting of a rigid outer container, a deformable inner bag filled with a liquid food, and valve means for the dispensing of the liquid food contained inside the bag. Generally, these valve means include a system for injecting a fluid under pressure into the gap between the outer container and the inner bag, so as to compress the latter, promoting the outflow of the liquid food.

[0006] In such known plastic kegs, the outer container, or at least the inner bag, is made of dark polymeric material or "barrier-coated" multilayer film material with an aluminum layer to avoid any exposure to light and the so-called "lightstruck flavor". However, a keg made of dark and opaque material does not allow the filling of the inner bag to be monitored visually, which could in the end be filled with foam instead of beer.

[0007] The object of the present invention is to overcome the drawbacks noted above for the known kegs, providing a disposable keg having features of high functionality, simplicity of construction and low cost.

[0008] Another object of the present invention is to provide a keg which ensures that any exposure to light and the so-called "lightstruck flavor" are avoided, while allowing the filling of the inner bag to be monitored visually .

[0009] Such objects, as well as others which will appear more clearly in the following, are achieved by a disposable keg according to claim 1, as well as by a filling method according to claim 6. The dependent claims describe preferred embodiments of the invention.

[0010] Further features and advantages of the present invention will become clearer in the light of the detailed description of a preferred but not exclusive embodiment of a disposable keg 1, illustrated by way of non-limiting example with the aid of the accompanying figures, wherein:

figure 1 shows a transparent keg for liquid foods according to the present invention, completely empty;

- figure 2 shows the keg of figure 1, almost completely full;

- figure 3 shows the keg of figure 1 provided with valve means 4 for filling the inner bag 2 with the liquid food and the subsequent delivery of the liquid food contained inside the bag 2;

figure 4 shows the filling system 6 of the keg according to the present invention;

- figure 5 shows the distribution system 7 of the keg according to the present invention.

[0011] With reference to the aforementioned figures, the "disposable" keg 1 will be advantageously usable for the distribution of beverages L, for example beer, wine, fruit juice, soft drinks.

[0012] As shown in figure 1, the keg 1 essentially comprises an outer container 3 and a deformable bag 2 arranged internally therein.

[0013] The inner bag 2 is a deformable bag, made of multilayer polymeric material, which may be filled with a liquid food.

[0014] The outer container 3 is a rigid shell made of blow- molded polymeric material.

[0015] The keg 1 also comprises valve means 4 adapted to allow both the filling of the bag 2 with the liquid food and the subsequent dispensing of the liquid food contained inside the bag 2.

[0016] The valve means 4 permit the entry of a working fluid F, for example carbon dioxide or compressed air, into the gap 7 between the outer container 3 and the deformable bag 2, in addition to the passage (loading and unloading) of the liquid food L from inside the deformable bag 2 outwards, and vice versa.

[0017] As shown in figure 3, the valve means are connectable with a coupling 19 (preferably of the bayonet type) , provided with an inlet 192 for the liquid food L and an inlet 193 for the working fluid F, and an inlet 194 for connecting with the valve means 4.

[0018] Preferably, the coupling 19 comprises a pressure regulator 197, suitable for measuring and/or regulating the pressure of the working fluid F.

[0019] During the filling stage (also called the kegging stage) , the keg 1 may be installed in a filling system 6 at breweries, cellars or similar, as shown in figure 4.

[0020] The filling system 6 comprises: a pressurized barrel 61 containing the liquid food L (for example beer), connected to a load line 62 of the liquid food L for filling the inner bag 2 of the keg 1; a counter-pressure line 63, connected to counter-pressure means 64, for injecting a pressurized fluid F (generally air) into the gap 7 between the outer container 3 and the inner bag 2.

[0021] During dispensing, the keg 1 may be installed in a distribution system 7 in public premises, such as bars, breweries, cellars, restaurants, or similar, to tap measured out amounts of liquid by means of a tapping device 65, as shown in figure 5.

[0022] The distribution system 7 comprises: a pressure vessel 68 of a working fluid F (generally air) connected to a pressure line 67 for the supply of the pressurized fluid F in the gap 7 between the outer container 3 and the inner bag 2; a discharge line 66 of the liquid food L contained in the inner bag 2 of the keg 1 for supplying the liquid food L to the tapping device 65.

[0023] During dispensing, the working fluid F compresses the deformable bag 2 from the outside to allow the liquid to rise up along a suction line 8 (or cannula) in fluid communication with the discharge line 66 via the valve means 4.

[0024] The deformable inner bag 2 may be made of a multilayer material which includes at least a first layer of food-grade polymeric material, for example polyethylene (PE) , at least a second layer of polymeric material, for example, polyamide (PA) .

[0025] The outer container 3 may be made of polyethylene terephthalate (PET) .

[0026] In a known manner, the preform will be obtained from polyethylene terephthalate granules, which, by blow molding, will create the new outer container 3 for the new keg 1.

[0027] Figures 1 and 2 show that the keg 1 is transparent or semitransparent : i.e., the inner bag 2 and the outer container 3 are made of transparent or semitransparent material which allows one to see the liquid food L present inside the inner bag 2. Such solution enables the inner bag to be monitored visually, so as to avoid, by appropriately adjusting the feed rate of the liquid food into the inner bag 2, the formation of foam, which would result in partial or in any case not optimal filling of the keg 1. [0028] In order to create a transparent keg that ensures protection from light in any and all circumstances to avoid the so-called "lightstruck flavor", the polymeric material used to make the inner bag 2 or the outer container 3 (or both) , is loaded with a UV radiation- absorbing additive.

[0029] In particular, as may be seen directly from the preceding description and the attached figures, in a preferred embodiment, the outer container 3 is completely transparent and also the inner bag 2 is completely transparent, so as to allow visibility of the liquid contained inside both during the entire filling operation of the inner bag 2, and when the keg is stored. This is particularly advantageous when the liquid contained is beer because it allows color variations of the beer to be monitored over time and allows the filling to be monitored from the initial stages.

[0030] In one embodiment, only the polymeric material used to make the inner bag 2 is loaded with a UV radiation- absorbing additive.

[0031] In a further embodiment, only the polymeric material used to make the outer container 3 is loaded with a UV radiation-absorbing additive.

[0032] In a still further embodiment, both the polymeric material used to make the inner bag 2 and the polymeric material used to make the outer container 3 are loaded with a UV radiation-absorbing additive.

[0033] Preferably, the additive is adapted to create a barrier to UV radiation, in particular those wavelengths between 300 and 380 nm, which are the most energetic. Preferably, the additive is adapted to absorb harmful UV rays by applying a protective filter to the contents of the keg, which otherwise would be altered by light.

[0034] Preferably, the additive is adapted to make the inner bag 2 or the outer container 3 (or both) , impermeable to UV radiation.

[0035] Preferably, the additive is present in a percentage by weight between 0.1% and 10%, preferably between 0.5% and 10%, and even more preferably between 1.5% and 5%.

[0036] In a preferred embodiment, the additive comprises Poly (oxy-1 , 2-ethanediyl ) , . alpha- [4- ( 3-butoxy-2-cyano-3- oxo-l-propen-l-yl ) . -2-methoxyphenyl ] - . omega . -hydroxy . Moreover, preferably, the additive comprises bis-4H-3,l- benzoxazin-4-one, 2 , 2 ' - ( 1 , 4-phenylene ) , preferably in a percentage between 5% and 20% by weight of the additive.

[0037] In one embodiment, the additive comprises Poly(oxy- 1 , 2-ethanediyl ) , . alpha- [4- ( 3-butoxy-2-cyano-3-oxo-l- propen-l-yl ) -2-methoxyphenyl ]-. omega . -hydroxy and bis-4H- 3, l-benzoxazin-4-one, 2 , 2 '-( 1 , 4-phenylene ) in a percentage by weight between 0.1% and 0.25% of the total polymeric material, preferably of the total PET. This allows adequate protection against UV rays especially in containers containing beer.

[0038] The Applicant has experimentally verified the UV absorption properties of an outer container 3 for a keg 1 (for example for beer) made of polyethylene terephthalate (PET) with the addition of a UV radiation-absorbing additive .

[0039] The process of blending the ingredients, pelletizing the blend, making the preform and the blow-molding thereof are known to the person skilled in the art.

[0040] The outer container 3 for a keg 1 thus prepared has been tested using the "visible and near UV transmittance" test. The light transmission curve in the near UV and visible region (from 200 to 780 nm) was then recorded by optical measurement conducted with a PERKIN ELMER UV/VIS spectrophotometer. The test shows that the sample (i.e. the outer container 3) totally absorbs UV rays.

[0041] This solution allows a transparent keg to be obtained that guarantees protection against exposure to light and avoids the so-called "lightstruck flavor".

[0042] An object of the present invention is also a visible filling method of a transparent keg which allows the filling of the inner bag 2 to be monitored in an optimal way without foam being formed.

[0043] Such filling method provides for the following steps :

- preparing a transparent keg 1 comprising a transparent outer container 3, a transparent deformable bag 2 arranged inside the latter, and valve means 4 for filling the bag 2 with the liquid food L;

- preparing a barrel 61 containing the pressurized liquid food L (for example beer) (the pressure of the liquid food called PL) , connected to a load line 62 of the liquid food L for filling the inner bag 2 ;

preparing a counter-pressure line 63, connected to counter-pressure means 64, for the injection of a pressurized working fluid F (generally air or carbon dioxide) the pressure of the working fluid called PC) in the gap 7 between the outer container 3 and the inner bag 2.

[0044] The method provides for:

- activating the counter-pressure means 64 and regulating them to a pressure PC equal to the pressure PL of the barrel 61 containing the liquid food L (PC=PL) ;

- opening the load line 62 of the liquid food L for filling the inner bag 2 ;

- reducing the pressure of the counter-pressure means 64 to allow the effective filling of the inner bag 2 (PCXPL) ;

- visually checking the actual filling of the inner bag 2;

- if the formation of foam is seen through the transparent keg 1, raising the pressure PC of the counter-pressure means 64 slightly to reduce the rate of filling of the inner bag 2; or

- if no formation of foam is seen through the transparent keg 1, proceeding with the filling of the inner bag 2.

[0045] Preferably, before activating the counter-pressure means 64, the method provides for:

- preparing a coupling 19 (preferably of the bayonet type) , provided with an inlet 192 for the liquid food L and an inlet 193 for the working fluid F, and an inlet 194 connecting with the valve means 4 ;

- connecting the coupling 19 to the valve means 4 of the keg 1 (via the connection inlet 194) ;

- connecting the load line 62 with the inlet 192 for the liquid food L and the counter-pressure line 63 with the inlet 193 for the working fluid F.

[0046] Preferably, the method provides for measuring and/or regulating the PC pressure of the working fluid F by means of a pressure regulator 197 provided on the counter-pressure line 63. [0047] From that which has been described above, it is clear that the invention achieves the intended ob ectives .

[0048] Innovatively, the transparent keg 1 according to the present invention allows the filling of the inner bag to be monitored visually, avoiding any exposure to light and the so-called "lightstruck flavor".

[0049] Advantageously, the transparent keg according to the present invention provides the possibility to know with a quick glance how much and which food product there is inside the inner bag 2, as well as to immediately check for the presence of foam or residues.

[0050] Advantageously, the transparent keg according to the present invention guarantees the maintenance of all the organoleptic qualities of the product contained therein, including during the tapping stage, leaving the liquid always under vacuum and eliminating any waste related to use .

[0051] It is clear that a person skilled in the art may make modifications to the above-described transparent keg, all contained within the scope of protection as defined by the following claims.

Claims

1. A keg (1) for liquid foods, for example, beer, comprising :

- an outer container (3) ;

- a deformable bag (2) capable of accommodating in its interior a liquid food (L) , said bag (2) being housed internally in said outer container (3) ;

- valve means (4) for filling and emptying the bag (2), wherein the inner bag (2) and the outer container (3) are made of transparent or semitransparent polymeric material, and

wherein the inner bag (2) and/or the outer container (3) are made of polymeric material loaded with a UV radiation-absorbing additive.

2. A keg (1) according to claim 1, wherein the additive is present in a percentage by weight between 0.5% and 10%.

3. A keg (1) according to claim 2, wherein the additive is present in a percentage by weight between 1.5% and 5%.

4. A keg (1) according to any one of the preceding claims, wherein the additive creates a barrier against UV radiations, in particular against those between 300 and 380 nm.

5. A keg (1) according to any one of the preceding claims, wherein the additive comprises Poly (oxy-1 , 2- ethanediyl) , .alpha- [4- ( 3-butoxy-2-cyano-3-oxo-l-propen-l- yl ) -2-methoxyphenyl ] - . omega . -hydroxy .

6. A keg (1) according to any one of the preceding claims, wherein the additive comprises bis-4H-3,l- benzoxazin-4-one, 2 , 2 ' - ( 1 , 4-phenylene ) , preferably in a percentage between 0.1% and 0.25% by weight of the total polymeric material.

7. A keg (1) according to any one of the preceding claims, wherein the outer container (3) is made of polyethylene terephthalate (PET) film, blow-molded, and loaded with a UV radiation-absorbing additive.

8. A keg (1) according to any one of the preceding claims, wherein the inner bag (2) is made of a multilayer material that includes at least a first polyethylene layer (PE) and a second polyamide layer (PA) , and at least one of the first layer and the second layer is loaded with a UV radiation-absorbing additive.

9. A keg (1) according to any one of the preceding claims wherein the outer container (3) is completely transparent and the deformable bag (3) is completely transparent.

10. A keg (1) according to any one of the claims, wherein the deformable bag (2) receives beer therein.

11. A method for filling a transparent keg (1), comprising the steps of: - preparing a keg (1) in accordance with any one of the preceding claims;

- preparing a barrel (61) containing the liquid food (L) at a pressure (PL) ;

- connecting the keg to the counter-pressure means (64) containing a working fluid (F) at a pressure (PC) for the injection of said fluid in a gap (7) between the outer container (3) and the inner bag (2);

activating the counter-pressure means (64) and regulating them to a pressure (PC) equal to the pressure (PL) of the liquid food (L) ;

connecting the keg (1) to the barrel (61) for the filling of the inner bag (2);

reducing the pressure (PC) of the counter-pressure means (64) to allow the effective filling of the inner bag ( 2 ) ;

- visually monitoring the filling of the inner bag 2.

12. A method for filling a transparent keg (1), according to claim 11, wherein the step of visually monitoring the filling of the inner bag (2) provides for:

if the formation of foam is seen through the transparent keg (1), raising the pressure (PC) of the counter-pressure means (64) slightly to reduce the rate of filling of the inner bag (2);

- if no formation of foam is seen through the transparent keg (1), proceeding with the filling of the inner bag (2) .

13. A method for filling a transparent keg (1), according to claim 11 or 12, wherein the pressure (PC) of the working fluid (F) is measured and/or regulated via a pressure regulator (197) .