BARICS STEVEN JOHN ANTHONY (AU)
| EP1429968B1 | 2006-04-26 | |||
| JP2004236582A | 2004-08-26 | |||
| EP1232694A1 | 2002-08-21 |
| 45 The claims defining the invention are as follows: 1. A filled aluminium container containing a wine characterised in that the wine has a pH between 2.9 and 3.5 and the filled container of wine has a molecular sulphur dioxide content of between 0.4 and 0.8 mg/L and further characterised in that prior to filling the wine was micro filtered in a multi stage microfiltration treatment wherein the filter pore diameters are 1.0 pm or less in the first stage filter housing and 0.20 pm to 0.45 pm in at least one subsequent stage filter housing. 2 A filled aluminium container as defined in claim 1 wherein the maximum oxygen content of the head space is 1% v/v and dissolved Oxygen levels throughout the aluminium container filling process are maintained at <0.5mg/L. 3 A filled aluminium container as defined in claim 1 or 2 wherein the filled aluminium container of wine has a molecular sulphur dioxide content of between 0.6 and 0.7 mg/L. 4 A filled aluminium container as defined in any one of claims 1 to 3 wherein the filter pore diameters are about 0.60 pm in the first stage filter housing and 0.30 pm to 0.45 pm in at least one subsequent stage filter housing. 5 A filled aluminium container as defined in any one of claims 1 to 4 wherein the wine is carbonated. 6 A filled aluminium container as defined in any one of claims 1 to 5 wherein the head space in the can has the composition nitrogen 80 - 97 % v/v and carbon dioxide 2 - 20 % v/v and preferably final levels of dissolved C02 are from 50 ppm to 800 ppm for white wines and 50 ppm to 400 ppm for red wines, prior to filling the container.. 46 7. A filled aluminium container as claimed any one of claims 1 to 6 in which the alcohol content is below 9 % v/v wherein sorbic acid is added at a level greater than 90 mg/L. 8. A method of filling an aluminium container with wine characterised in that the wine has a pH between 2.9 and 3.5 and the filled aluminium container of wine has a molecular sulphur dioxide content of between 0.4 and 0.8 mg/L and further characterised in that prior to filling the wine was micro-filtered in a two stage microfiltration treatment wherein the filter pore diameters are 1.0 pm or less in the first stage filter housing and 0.20 pm to 0.45 pm in at least one subsequent stage filter housing. 9. A method of filling an aluminium container with wine as claimed in claim 8 wherein the filter pore diameter is about 0.60 μητι in the first stage filter housing and 0.30 pm to 0.45 pm in at least one subsequent stage filter housing. 10. A method of filling an aluminium container with wine as claimed in claim 8 or 9 in which the alcohol content is below 9% v/v wherein sorbic acid is added at a level greater than 90 mg/L. |
This invention relates to aluminium containers filled with wine. It also relates to a process for packaging wine and wine products in aluminium containers.
Background of the Invention
Wine has been produced since the times of the ancient Greeks. It has been stored in many types of containers. These have included timber, pottery and leather. The use of glass bottles has evolved as the preferred storage means for wine, particularly when stored in quantities less than one litre. While bottles are almost universally used, they have the disadvantages of having relatively high weight and being relatively fragile making them difficult to maintain the wines integrity during transport globally.
For beverages other than wine, such as beer and soft drinks, alternative packages such as metal cans and polyethylenetetraphthate (PET) bottles have been widely adopted. These offer advantages of lower weight and greater resistance to breakage. It has been proposed to store wine in such alternative containers. However, attempts to use such packaging types for wine storage and transport globally whilst maintaining its original integrity have been generally unsuccessful. Some very low quality wines are stored in polyvinyl chloride containers with short shelf life and stability.
It is believed that the reasons for this lack of success in canning wine has been the relatively aggressive nature of the materials in wine and the adverse effects of the reaction products of wine and the container on the wine quality, especially taste. Wine is a complex product that typically has a pH in the range 3 to 4. This compares to beer with a pH of 5 or more and many soft drinks with pH 3 or less. However, pH itself is not the sole determinant, and it has been found that carbonated cola drinks with a pH as low as 3 may be adequately stored in PET containers as they are short shelf life products. The low pH is the result of the phosphoric acid content in carbonated cola drinks. This may allow the
satisfactory use of pre-coated aluminium cans and PET bottles for these beverages but not for wine or wine products.
In Modern Metals (1981; p28) Fred Church suggested packaging wine in two piece aluminium cans by eliminating oxygen from the head space with nitrogen. This early proposal failed to achieve commercial success because the wines were not storage stable.
In 1992 Ferrarini etal in Ricerca Viticola Id Enologica no 8 p59 reviewed the packaging of wine in aluminium cans. They also concluded that oxygen in the head space was to be avoided but that corrosion of the can was due to a number of contributing factors which needed to be addressed. Ferrarini noted that high internal pressures tend to accelerate the corrosion process and also stipulated that pasteurization was necessary. Ferrarini et al concluded that by using these recommendations that a specific white wine could be canned, however it had a 100% failure rate after 50 days storage. Therefore these recommendations did not produce a commercially viable product. Again these recommendations failed to provide a solution to the long held problem of canning wine whilst maintaining its integrity in storage and transport and did not result in any commercially successful product. It has been realized that pasteurisation has detrimental effect on the taste and bouquet of wine and this may in addition explain the lack of adoption of the Ferrarini recommendations.
EP 1429968 disclosed a method of packaging wine in aluminium cans which utilized a combination of selection of wines having upper limits of Sulfates and chlorides, limiting the addition of sulphur dioxide, using a corrosion resistant liner and pressurizing the can. This resulted in an acceptable shelf life.
Products such as wine and wine based products that are extremely active and aggressive and continuously interactive with their environment require their chemical balance to be created and then maintained in order for the products integrity (sight, aroma and taste) to be delivered intact in the aluminium container to the consumer as the winemaker had intended. With global markets opening for wine, winemakers wish to deliver their products to the global consumer the way they have made the wine. This is extremely difficult in a global market with its varying weather conditions, temperature fluctuations, quality and capability of logistics systems to maintain the wines' integrity until it reaches the consumer. Hence the need for a product that delivers an exact equilibrium to maintain the wines integrity under global transport and storage conditions based on a proven integrated wine packaging system that delivers a consistent quality product every time is required to solve this problem. In addition this product (and the system supporting it) needs to reflect the consumers desire for environmentally sustainable packaging in order to minimise its overall carbon footprint but at the same time allow the delivery of a wine that maintains its integral balance and profile from the winemaker to the consumer no matter where that consumer is located with a stable shelf (up to and over 12 months) has been a long felt commercial requirement for winemakers and wine vendors globally.
Shelf life is defined as the period after packaging during which wine retains its intended appearance, aroma and taste and is likely to be regarded as palatable by a consumer. The concept of shelf life implies that, over time wine can change after packaging from a product showing the attributes of a designed and intended quality or style to a product with a significantly lowered quality or different style. This change is significantly attributable to the packaging medium used, especially in aluminium containers, that the wine is stored and transported in which can negatively impact on these essential wine characteristics commencing once the wine is packaged with significant changes occurring in less than 6 months.
It is an object of this invention to package wine in aluminium containers whereby the quality of the wine does not deteriorate significantly on storage and transport the shelf life remains stable up to and beyond 2 years.
Summary of the Invention
This invention provides in one form a filled aluminium container containing a wine characterised in that the wine has a pH between 2.9 and 3.5 and the filled container of wine has a molecular sulphur dioxide content of between 0.4 and 0.8 mg/L preferably 0.6 to 0.7mg/l and further characterised in that prior to filling the wine was micro filtered in a multistage microfiltration treatment wherein the filter pore diameters are 1.0 pm or less in the first stage filter housing and 0.20 μητι to 0.45 pm in at least one subsequent stage filter housing. Preferably the filter pore diameters are larger in the first stage filter housing than in the subsequent stage filter housing. More preferably, the filter pore diameters in the first stage filter housing are larger than 0.45 pm, preferably at least 60 pm. According to one embodiment, the filter pore diameters in the first stage filter housing are about 0.6 pm. This invention is predicated on the discovery that microbial spoilage of wine after packaging can cause significant quality issues and dramatically reduce shelf life and stability. Effective control of microbial populations in packaged wine in an aluminium container must be carried out at filling to ensure ongoing stability. According to a preferred embodiment, free sulphur dioxide, dissolved oxygen levels and/or dissolved carbon dioxide levels should be controlled to optimize prevention of the wine from oxidation and microbiological deterioration . In particular, the free sulsulphur dioxide level should be controlled as discussed herein to optimize the results.
It has been surprisingly found that the multistage filtration according to the present invention gives superior results as compared to a single stage filtration regarding the effectiveness, the taste and the long term stability of the wine. Microfiltration is generally understood as filtration using 1.0 μηι filter pore size and lower, preferably using 0.6 μπι filter pore size (diameter) and lower. The microfiltration steps are carried out preferably in filter housings. The term "filter housing" is to be understood according to one embodiment as a synonym for "filter unit", "filter device", "filter stage" or "filter". The pore sizes indicated herein refer to the pore diameter if not indicated otherwise. It is assumed that the combination comprising or consisting of a first filter stage as set out above, preferably with a filter having pores of at least 0.60 m, with a subsequent filter stage as set out above, having a filter with pore sizes from 0.20 pm to 0.45 pm, preferably from 0.30 μιη to 0.45 Mm, allows efficient and stable retention of all relevant microorganisms and at the same time avoids undesired removal of other colloidal or aggregated components in the wine which are important for structural stability and optimum taste of the wine. Without being bound to this theory, the sequence of these filtration stages may beneficially influence the interaction of the respective filter retentates with desired colloidal components and aggregates in the wine, avoiding excess removal of desired components from the wine.
In this invention microfiltration (preferably sterile grade) microfiltration is used to remove bacteria and yeasts from the wine prior to filling.. Removal of microbial cells is best achieved by implementing a double in line sterile grade membrane filtration system using a grade with fine enough pores to remove all yeast and bacteria likely to be found in wine but not damage the integrity of the wine. The preferred pore diameters for this purpose are 0.60 pm in the first stage filter housing and in the second stage filter housing 0.30 pm to 0.45 pm. Filter integrity testing ensures that the filters ability to retain bacteria has not been compromised and there are no damaged membranes (pores) present that may allow the passage of microbial cells in the wine.
The size of the filter pores indicates the size exclusion characteristics of the filter, i.e. a filter with a pore size of 0.60 pm will filter off particles of above 0.60 pm. The size of the filter pores is indicated for commercially available products and can be determined by standard methods known to the skilled person.
To ensure successful membrane filtration, the filters are preferably sterilised correctly and tested for integrity prior to use. The sterilizing time and temperature regime is preferably 80°C for 20 minutes.
After membrane filtration, successful sterile canning of wine requires filling through sterilised equipment. All equipment, including the onsite wine storage tank downstream from the final membrane filter (lines, valves, filler etc) are preferably sterilised and operated in a sterile state. Preferably the filling heads are sprayed with 70% ethanol prior to start up and repeated when filler downtime exceeds 10 minutes. Preferably a full sterilization is performed if the filler is subjected to down time longer than 4 hours.
Molecular S0 2 is the form of free S0 2 that has antimicrobial action. International wine organisations and regulatory bodies such as the Australian Wine Research Institute (AWRI) recommends at least 0.825 mg/L of molecular S0 2 in wine to eliminate cell viability.
Sulphur dioxide (S0 2 ) is an antioxidant that can be added to wine. The addition of SO2 in this invention is to inhibit the reaction of oxygen with the wine and to prevent damage to the wines integrity; colour, aroma and flavour compounds. The term "the filled container of wine has a molecular sulphur dioxide content of ..." preferably means that the wine filled in the container has the respective molecular sulphur dioxide content.
This invention is in part based on the discovery that excess levels of Free S0 2 will elevate the wines corrosive effect on the can and can lining used in today's can manufacturing. In addition the inventors have found that it will also affect the nose (odour-sulphidic characters) and the taste (sharp, astringent) of the wine in the finished product. Low levels of Free S0 2 will reduce the shelf life, stability and quality of the wine in the finished product. Therefore we have invented a product and the protocols to balance these competing effects on wine in an aluminium container that is outlined in this patent.
In this invention the functions of S0 2 for wine in aluminium containers include the control of microbiological issues and minimise oxidation affects in the wine in an aluminium container. For wine at filling to have a Free S0 2 level of <35 ppm the wirie, ex winery, is preferred to be Free S0 2 level of 38 - 44 ppm this final ppm level dependent on the distance from winery to the filling plant. Free SO2 depletion rate is approximately 2 - 3 ppm per day during transport and during storage at filling facility this needs to be taken into consideration when preparing the wine for transport from the winery to the filling facility.
At a pH of 3.5, wine with 35 mg/L of free S0 2 contains 0.70 mg/L of molecular SO2, lower than the recommended AWRI minimum to eliminate cell viability. Wines filled according to this invention will not contain sufficient free S0 2 to eliminate cell viability.
According to one embodiment of the invention, the wine contains from 32 to 35 mg/L of free S0 2 at the time of filling .
However, this invention is predicated on the discovery that these structured wines will contain sufficient molecular S0 2 to inhibit microbial growth without negatively impacting on the wines integrity in an aluminium container. Given that the primary control mechanisms in place are sterile grade membrane filtration and preferably filler sterilization, this level of molecular S0 2 has been found to be adequate as an adjunct to prevent microbial spoilage.
Using the protocols of this invention outlined in the patent it is not necessary to use post-packaging pasteurisation (heating) to inactivate microbial cells in the filled aluminium wine containers.
Wine in an aluminium container with low alcohol content is particularly susceptible to microbial spoilage. In this invention where the wines have less than 9 % v/v alcohol the antimicrobial agent sorbic acid is added at a level greater than 90 mg/L preferably greater than 120 mg/L. This addition will assist in preventing microbial growth and spoilage of the product in storage and transport.
Preferably the maximum oxygen content of the head space is 1 % v/v.
Preferably the head space after sealing with the closure has the composition nitrogen 80 - 97 % v/v, and carbon dioxide 2 - 20 % v/v. In a 250 ml container the head space volume is less than 3 ml preferably less than 2ml and more preferably about 1ml. Generally the head space volume is less than 1 % preferably less than 0.5 % of the sealed volume of the container.
Preferably dissolved Oxygen levels throughout the aluminium container filling process are maintained up to 0.5 mg/L. and final levels of dissolved CO 2 are up to 1200 ppm for still white wines and higher for sparkling wines, prior to filling the container. For red wines final levels of dissolved CO2 are preferably up to 400 ppm prior to filling the container.
Preferably liquid nitrogen is added just prior to the seaming of the closure to the body of the aluminium container.
Alternatively the wine is carbonated before it is filled in the aluminium container whereby the head space after sealing is predominantly carbon dioxide.
The pressure within the aluminium container is preferably maintained at a pressure above 15 psi at 4°C, so that the corrosion resistant lining in the aluminium container is less likely to fracture or crack exposing fissures as a result of external container damage in storage and transport. In addition the walls of the container are less likely to be buckled which can also lead to damaging the internal lining which can then damage the integrity of the wine.
References to conditions prior to or at the time of filling preferably mean immediately prior to filling or at the time of filling the container.
Preferably the corrosion resistant coating is a thermoset coating and of greater thickness as opposed to the usual industry lining specifications in aluminium containers used to package soft drink and beer that are not suitable for wine/wine products.
Yeasts are the most likely cause of microbial spoilage in packaged wine due to their tolerance of alcohol, low pH and anaerobic conditions. We have discovered that Yeast growth in wine in an aluminium container is inhibited by high volumes of carbon dioxide. Sparkling wine packed according to this invention contains high levels of carbon dioxide, preferably 3.3 - 3.8 volumes. Yeast growth in sparkling wine packaged using the protocols in this invention are extremely unlikely.
Preferably the wine is chilled before filling.
This invention may be used for still and sparkling wines (including fortified, sweet and semi sweet wines) and also wines mixed with mineral water,
juice, flavours etc.
The advantages that result from using a multistage micro-filtration with lower free sulphur levels include:
• Increased shelf life
· Less spoilage
• Refermentation virtually zero.
• Susceptibility for blown cans zero.
• Maintain wine profile- nose, taste, colour The reference to the features or protocols of the present invention in the
present specification is to be understood to include all possible
combinations of the single features unless these features are pure
alternatives. Thus, the single features are combinable within the scope of the present invention as determined by the attached claims.
Detailed Description of the Invention
Preferred embodiments of the invention will now be described.
In filling aluminium containers with wine there is a need to preserve the wine in the state it is in at the time of filling and to guard against microbial deterioration of the wine. In bottled wine sulphur dioxide has been used to control microbial
deterioration but corked bottles allow for dissipation of excess sulphur dioxide. In the hermetically sealed environment of a .an aluminium container too much sulphur dioxide can affect the wine and also lead to corrosion of the container and liner further affecting wine quality and shelf life.
Figure 1 illustrates this problem.
Grape Varieties used in in the preferred embodiments of the invention are shown in Table 1. In all the tables used in this specification, individual results have been combined and averaged. References to ranges of values for pH, free sulphur alcohol content reflect that all of the wines in the specified range had the characteristics observed. All wine analytical results are determined by a world recognised NATA accredited laboratory. All results are issued in accordance with NATA accreditation
requirements which include the requirements of ISO/IEC 17025 and are traceable to national standards of measurement.
Table 1
Molecular Sorbic
Grape Variety used in these Alcohol Sulphur acid patented protocols pH Range Range Range Range
Cabernet 3.2 to 3.5 >9% 0.4 to 0.8
Shiraz 3.2 to 3.5 >9 0.4 to 0.8
erlot 3.2 to 3.5 >9% 0.4 to 0.8
Still Red Malbec 3.2 to 3.5 >9% 0.4 to 0.8
Grenache 3.2 to 3.5 >9% 0.4 to 0.8
Zinfandel 3.2 to 3.5 >9% 0.4 to 0.8
Tempranillo 3.2 to 3.5 >9% 0.4 to 0.8
Chardonnay 2.9 to 3.5 >9% 0.4 to 0.8
Sauvignon Blanc 2.9 to 3.5 >9% 0.4 to 0.8
Semillon 2.9 to 3.5 >9% 0.4 to 0.8
Still White
Riesling 2.9 to 3.5 >9% 0.4 to 0.8
Pinot Gris 2.9 to 3.5 >9% 0.4 to 0.8
Chenin Blanc 2.9 to 3.5 >9% 0.4 to 0.8
Shiraz 3.2 to 3.5 >9% 0.4 to 0.8
Pinot Noir 3.2 to 3.5 >9% 0.4 to 0.8
Sparkling Red Cabernet 3.2 to 3.5 >9% 0.4 to 0.8
Merlot 3.2 to 3.5 >9 0.4 to 0.8
Durif 3.2 to 3.5 >9% 0.4 to 0.8
Pinot Noir 2.9 to 3.5 >9% 0.4 to 0.8
Pinot Meunier 2.9 to 3.5 >9% 0.4 to 0.8
Chardonnay 2.9 to 3.5 >9% 0.4 to 0.8
Sparkling
Pinot Blanc 2.9 to 3.5 >9% 0.4 to 0.8
White
Riesling 2.9 to 3.5 >9% 0.4 to 0.8
Glera (Prosecco) 2.9 to 3.5 >9% 0.4 to 0.8
Cava grape varieties 2.9 to 3.5 >9% 0.4 to 0.8 Combination of Red &
Sparkling
White varieties outlined 2.9 to 3.5 >9% 0.4 to 0.8
Rose
above
Moscato 2.9 to 3.5 <9% 0.4 to 0.8 >90mg L
Muscat Blanc 2.9 to 3.5 <9% 0.4 to 0.8 >90mg/L
Low alcohol Chianti 2.9 to 3.5 <9% 0.4 to 0.8 >90mg L and wine Sangria 2.9 to 3.5 <9 0.4 to 0.8 >90mg L based
Most varieties as
products
detailed in Table 14.-
2.9 to 3.5 <9% 0.4 to 0.8 >90mg L Pending style
requirements
Wine Filling Protocols
Commencing with the rinsing of the aluminium container for wine pre- filling and following on to the aluminium container post filling and then the rinsing of the container via the warming tunnel, all these procedures require the interaction of the water with either the empty container or the filled finished product.
Water is the most strictly controlled ingredient from a regulatory perspective.
It must be potable (safe) and palatable (good tasting).
Water can have a direct impact on the sensory profile and stability of wine in an aluminium container. This will occur if hoses and filters are not washed with
quality filtered water. This will also occur if process equipment is not rinsed with clean quality filtered water.
Treated water for filter washing and filling machine washing in this invention:
• Must meet all applicable local standards and guidelines.
• Must meet the health-based guideline values of the World Health
Organization (WHO).
• Must meet all requirements that are product-specific as they relate to
stability, shelf-life, and sensory profile of all wine in an aluminium
container.
In addition, treated water preferably will comply with the maximum level of
constituents in table 2. Table 2
Chlorine may be used to sanitise equipment but it is preferably completely removed by rinsing with water prior to use of the equipment with wine.
Rinsing of empty aluminium containers with oxidants prior to use can create residues that react with S0 2 . The protocol is that aluminium containers are preferably rinsed with filtered water only.
Pre filling: Should the water quality fall below the listed specifications above the resulting possible increased microbiological load would negatively impact on the integrity of the wine quality, stability and longevity of the filled product.
Increased microbiological load would also deplete the Free S0 2 levels in the wine resulting in shorter shelf life, stability and an extra potential for spoilage on storage and transport.
Post filling: should the water quality fall below the listed specifications above the resulting possible increased microbiological load would affect the integrity of the can/container lid tab score lines, resulting in 'leakers' and or exploding aluminium containers. We have discovered that this increased microbiological loads effect on the aluminium container has been responsible for the loss of entire shipments of wine in aluminium containers causing significant commercial damage.
Additionally without proper water quality management there is a potential for mould formation to occur in any crevice of the container. This microbiological issue is also responsible for increasing the spoilage from leakers in storage and transport.
A preferred sterile grade filter pore diameter for this purpose is 0.30 pm - 0.45 pm as part of this invention of an integrated wine packaging system to control these microbiological issues in wine in aluminium containers. Preferably the levels for Total Plate Count, Yeasts and Moulds and Lactobacillus are all <1.
The limits and processes of this invention ensure that all products are
microbiologically stable without impacting on wines integrity - its key notes (sight, nose and taste) that can damage the commerciality of the product.
Pasteurisation can also damage the key notes (integrity) of wine in an aluminium container.
Tables 3a and 3b below outlines effects of microbiological growth and sulphur levels we have discovered impacts on the integrity of the wine when packaged in an aluminium can/container that this inventive step outlined in the patent protocols solves. Table 3a illustrates Wine parameters (Organoleptic, Corrosion,
Microbiological) at a pH of 2.9 to < 3.5 and >9% alcohol.
Table 3a.
Wine parameters (Organoleptic, Corrosion, Microbiological) at a pH of 2.9 to < 3.5 and >9% alc/vol
Free
so 2
(ppm) pH Al
c/v Parameter Initial 6 months 12 months 18 months 24 months
2.9 to >9% Organoleptic Fresh and clean Dull Flat Oxidation Reductive Spoiled
< 3.5 characters
Corrosion nil corrosion nil corrosion nil corrosion nil corrosion nil corrosion
Microbiologic Microbiological Microbiological<l cfu Microbiologica Microbiolog Microbiological <lcfu
< 10 al<lcfu <lcfu Klcfu ical <lcfu
Monitor SO 2 Increased microactivity. 'Blown' cans. Testing ceased
Microbiolc depletion Continued Minimal Spoiled
al >lcfu Free SC¾ depletion FreeS02
level
2.9 to >9% Organoleptic Fresh and clean Fresh and clean Fresh and clean Fresh and Fresh and clean < 3.5 clean
Corrosion nil corrosion nil corrosion nil corrosion nil corrosion nil corrosion
10-35 Microbiol Microbiological Microbiological 1 cfu Microbiologica Microbiolog Microbiological < 1 cfu ogical <lcfu Klcfu ical <lcfu
<lcfu
Microbiol Monitor SO 2 Monitor SO 2 depletion Continued S0 2 Stabilised Stabilised FreeSC^ ogical depletion depletion FreeSOz levels
>lcfu levels
Table 3b below shows organoleptic results with varying microbial levels;
Tabl 3b
Filtration; Preferably, a two stage in line sterile filtration microbiological control system is used.
Wine Filter Management
This invention does not utilise post-packaging pasteurisation (heating) to inactivate microbial cells. Rather microbial cells are removed prior to filling. The removal of microbial cells is achieved by filtration, preferably membrane filtration, using a sterile grade with fine enough pores to remove yeast and bacteria likely to be found in wine.
A multistage filtration method is used with preferably two stages but additional stages may be used.
Filters according to a prefrerred embodiment:
Stage 1 ; 0.60 m filters are preferably used as primary filters to remove yeast cells from the wine to prevent yeast build up and spoilage including the significant risks associated with any secondary fermentation inside the container.
The use of the first (e.g. 0.60 m filter) filtration level is essentially to
microbiologically stabilize the wine by removing and controlling the reformation of foreign and cultured organisms and removal of bacteria and yeast cells. This stage is designed to remove the majority of bacteria and yeast cells in the wine without damaging the wines integrity.
Stage 2. 0.30 μιη-0.45 μπι sterile grade filter is preferably used in the subsequent filtration of the wine prior to filling to prevent microbiological issues occurring in the wine in an aluminium container finished product.
The second stage (0.30 μιη - 045 μιη) is to guarantee sterility whereby the bacteria and yeast cells are completely removed and the potential for secondary fermentation and spoilage occurring in the filled wine in an aluminium container is eliminated. Again the requirement is not to damage the wines integrity. Once this stage is complete it removes the likelihood of any secondary fermentation occurring inside the aluminium wine container that could result in it exploding during storage and transport. This secondary fermentation can also be the cause of 'leakers'. This system eliminates the need to use pasteurisation to
microbiologically stabilise the wine which would negatively impact on the wines integrity but is not required with this invention; The Tables below outline the results of wine constructed using these protocols outlined in this patent;
Table 4a shows organoleptic Results with Two Stage microbiological filtration and zero (<5) Free SO2;
. Table 4b shows organoleptic Results - zero microbiological filtration;
Table 4c shows organoleptic results Red (still, carbonated and sparkling) wine with two stage sterile grade microbiological 5 filtration;
Table 4 d shows organoleptic results White wine ((still, carbonated and sparkling) with two stage sterile grade microbiological filtration.
TABLE 4 a
S0 2 levels measured at the time of filling
Table 4b
S 2 evels measured at t e time of filling
Table 4c .
Organoleptic Alc/vol
Results
Filter Grade-pm 9% PH Molecular initial 3 months 6 months 9 months 12 18 months 24 months
S02 months
9% 2.9 0.4 to Minor loss Expired.
Volatile
to<3.5 0.8 of flavour
Acid
1.0 Refermentation
Fresh Full characters
Spoiled off Expired Expired
taste Issues
Blown
cans
9% 2.9 0.4 to Fresh Full Spoiled Expired
Refermentation
to<3.5 0.8 taste off
Fresh Full Slight issues Blown cans
0.60
taste cloudiness
Two stage micro .>9% 2.9 0.4 to Fresh Full Fresh Fresh Full Fresh filtration (0.60pm- to<3.5 0.8 taste Full taste Full taste
Fresh Full
0.45pm) Fresh Full taste Fresh Full taste
taste
taste
Two stage micro .>9% 2.9 0.4 to Fresh Full taste Fresh Fresh Full Fresh filtration (Ο.βθμην to<3.5 0.8 Full taste Full taste 0.30 m) Fresh Full Fresh Full taste
Fresh Full taste taste
taste
.>9% 2.9 0.4 to Filter blockage. Sulphidic Metallic taste Spoiled Not fit for
to<3.5 0.8 Fine sediment characters. off consumptio
0.45 in the wine. Astringent. Sediment in n
Unacceptable the bottom of
'gritty' can. Bitter
Mouth feel. taste
Higher Free
S02 levels.
Slight S02
aroma.
.>9% 2.9 0.4 to Varietal
to<3.5 0.8 flavour loss.
<0.30 Colour less
intense. Filter
blockage.
S0 2 level Is measured at the time of filling
Table 4d.
9% [2.9 0.4 to varietal to<3.5 0.8 Flavour loss.
<0.30 Colour less intense. Filter blockage.
* S0 2 levels measured at the time of filling
Final filtration using filters with pore sizes of C60 + 0.45, 0.60 + 0.30 or 0.60 + 0.20 allows sterile filtration be achieved. Using the 0.20 pore size filter may be applicable however the likelihood of stripping the wine of colour and flavour is increased and therefore may not be suitable in some cases.
A single 0.45 filtration of the wine
• would enhance the risk of live cells being forced through the filter and into the finished wine.
· Require extra S0 2 dosing to offset the risk of higher microorganism and yeast levels in the wine resulting in higher Free S02 levels in the wine.
• Shelf life of the wine in a can would be diminished (less than 12 months) due to the increased corrosive effect of high SO 2 levels.
• Wine would develop sulphidic (H2S)characters.
· Without the addition of extra S0 2 the wine would be subject to a greater risk of refermentation in the can( from the yeast cells) and spoilage (bacteria cells)
• would enhance the risk of fine sediment escaping into the finished
wine. This would eventually show up (approximately 6-12 months)in the bottom of the can. Totally unacceptable to the consumer(a gritty mouth feel).
The above tables illustrate the surprising improvement in the shelf life term during which the original organoleptic values, colour and flavour of wine is preserved without deterioration.
Correct filter and filter housing preparation is a key protocol to successful wine in an aluminium container production.
The inventors have found that for wine in an aluminium container poorly sanitised or prepared wine filters and filter housings will lead to microbiological complications within the wine in the container.
During storage, the sterile grade filters are preferably stored in a solution of 1 % Citric Acid with 50 ppm Free SO2. This is preferably made fresh and repeated on a fortnightly basis. Prior to filling the aluminium container, the filters are preferably sterilised and tested for integrity prior to use.
The preferred sterilising time and temperature regime is 80°C for 20 minutes.
The results of trials utilizing the protocols outlined in this patent for microfiltration with varying amounts of added free sulphur are shown in table 5 for a white wine table 6 for a red wine table 7 for a carbonated white wine and table 8 for a carbonated red wine. These wines were prepared according to the protocols outlined in this patent.
Table 5.
* S0 2 levels measured at the time of filling
Table 6. Red wine prepared according to this invention 24 month appraisal below;
* S0 2 levels measured at the time of filling
Table 7.
* S0 2 levels measured at the time of filling
Table 8.
* S0 2 levels measured at the time of filling
The Total SO 2 in wine (the total amount of Free and bound SO2) is directly related to the levels of S0 2 added during the wine making process and during the storage of the wine at the winery.
Wine making practices in accordance with this invention require the
avoidance of oxygen interaction throughout the entire winemaking
process thereby limiting the continued addition of SO2.
Acetaldehyde is caused by excessive oxidation of the wine.
The addition of SO2 to the Oxidised' wine will bind the acetaldehyde,
removing its volatile presence and resulting in a wine with a "fresher"
aroma.
Surprisingly this invention limits the frequency of oxidation and will greatly reduce the requirement for SO2 addition. This is the opposite to the usual commercial winemaking procedures practiced globally.
Table 9 shows the organoleptic assessment of Total SO 2 in wine
prepared according to the method of this invention;
Table 9;
Organoleptic
Results
Total S0 2 ppm Alc vol PH initial 6 months 9 months 12 months 18 months 24 months
100 >9% 2.9 Fresh Full taste to<3.5 Fresh Full Fresh Full Fresh Full taste.
Fresh Full taste. Clear Fresh Full taste.
taste taste Clear
250 >9% 2.9 Fresh Full taste. Clear Volatile Acid to<3.5 Fresh Full Fresh Full fresh Minor loss of characters
Fresh Full taste
taste taste flavour
300 >9% 2.9 Dull Volatile Acid Acetaldehyde.
Strong
to<3.5 Fresh Full characters spoiled
Stringent. Flat Volatile Acid
taste
characters
These results show the unexpected improvement in shelf life by limiting the addition of SO2 in combination with multi stage microfiltration.
Oxidation:
Oxidation of wine after packaging is caused by reaction of wine components with oxygen. Oxygen can be present in the wine at filling or present in the package headspace at sealing. The dissolved oxygen in the wine at filling and the oxygen in the headspace comprise the total oxygen load at filling. Oxygen can also enter the package after filling.
Oxidation is inhibited by the presence of antioxidant compounds in the wine. The following factors influence the extent and rate of oxidation reactions that take place in the wine after packaging is completed.
Preferably Dissolved Oxygen (DO) levels throughout the filling process are maintained up to 0.5 mg/L. and controlling the final maximum DO levels in the wine is preferred. This is in combination with limiting the oxygen levels entrapped within the headspace of the filled product, will greatly reduce the likelihood of oxidation, corrosion and or degradation of the product.
Dissolved Oxygen level is the amount of oxygen aeration sustained by the wine at any given time during the wine making process. These levels generally diminish as the wine consumes oxygen and oxidation results. Therefore the greater the DO levels at any given time in the wine the greater likelihood of increased oxidation. The outlined winemaking procedures ensure that the likelihood of oxygen coming into contact with the wine is inhibited. Under this system Oxygen management in wine is a key factor to consider for maintaining wine quality and integrity.
Strict adherence to Dissolved Oxygen (DO) specifications is critical in achieving product quality, stability and longevity. It is preferred to maintain as close to zero headspace in all vessels involved in the winemaking process to eliminate any possible oxygen element affecting the wine.
The integrated system outlined in this patent also manages this issue at filling by avoiding aeration of the wine via faulty fittings and /or avoidance of aeration of the wine at low temperatures as the absorption of oxygen is far greater at lower temperatures. Wine in tank prepared for filling can contain significant amounts of dissolved oxygen. Oxygen can also enter wine during delivery from the tank to the filler and during the filling process.
Any dissolved oxygen in the wine at filling is available for oxidation reactions with wine in the package, potentially limiting shelf life.
Dissolved oxygen in wine at filling may be achieved by controlling the maximum wine dissolved oxygen content in tank prior to fill and after delivery of wine into the package.
In the method of this invention the dissolved oxygen may be minimised in wine in the tank prior to filling by sparging the wine with nitrogen gas.
Sparging
This system minimizes the negative influence of Dissolved Oxygen in the wine with the use of sparging with nitrogen gas prior to filling. It is a benefit of this invention that dissolved oxygen reduction for wine in an aluminium container achieves stability, extended shelf life and maintains the wines integrity under production, storage and transport.
Excessive sparging may result in damage to the wines integrity by reducing the flavour profile and imparting a bitter character presumably caused by dissolved nitrogen. Therefore, according to a preferred embodiment, the amount of nitrogen . used for sparging is between 0.1 and 0.8 liter 2 per liter of wine
Preferably dissolved oxygen at winery and after wine transfer to tanker is less than 0.5 mg/L. Preferably the dissolved oxygen in storage tank at filling facility prior to canning is less than 0.5 mg/L.
Preferably the maximum wine dissolved oxygen content is less than 0.5 mg/L after filling of the wine into the container. This preferred maximum level will prevent significant loss of shelf life due to oxygen dissolved in the wine at filling. The tables below illustrate the organoleptic assessment of Dissolved Oxygen in wine;.
Table 10a. shows Red Wine - Dissolved Oxygen levels prepared according to the invention and without the DO controls of this invention
Table 10b. White Wine - Dissolved Oxygen levels prepared according to the invention and without the DO controls of this invention
Note; SO2 levels in the tables below -10a & b are measured at the time of filling
Table 10a.
Organoleptic
Results
Wine -DO Molecular alc/vol PH
levels so 2 initial 3 months 6 months 12 months 18 months 24 months
0.4 to 0.8 >9% 2.9 to Fresh Fresh Fresh Fresh Fresh
<3.5 Crisp clean Lively. Good nose. Sustained Sustained
Fresh Full flavour Clear bright wine wine Bright character character
<0.5 colour
0.4 to 0.8 >9% 2.9 to Spoiled
<3.5
Colour enhanced
Non DO Reductive Over
controlled wine characters developed
1.0 Fresh Fresh Oxidised Spoiled
0.4 to 0.8 >9% 2.9 to Expired
<3.5
Non DO Reductive Reductive
controlled wine characters characters
1.5 Fresh Over developed Oxidised Spoiled
Table 10b
Organoleptic
Results
Molecular alc/vol pH
S0 2
Wine -DO levels initial 3 months 6 months 12 months 18 months 24 months
0.4 to 0.8 >9% 2.9 to Fresh Fresh Fresh Fresh Fresh
<3.5 Crisp clean Lively. Good nose. Sustained Sustained wine character
Fresh Full flavour Clear bright wine character Bright
<0.5 colour
0.4 to 0.8 >9% 2.9 to Spoiled
Non DO <3.5 Colour Over
controlled wine Reductive enhanced developed
1.0 Fresh characters Oxidised Spoiled
0.4 to 0.8 >9% 2.9 to Expired
<3.5
Non DO Reductive Reductive
controlled wine characters Over characters
1.5 Fresh developed Oxidised Spoiled
Dissolved Carbon Dioxide (DCO2)
Carbon dioxide is naturally created during the wine fermentation process. During the maturation of the wine in storage most of the dissolved CO2 has been completely depleted or to acceptable levels of 'spritz' (400 ppm - 800 ppm).
Preferably all wine is cross flow filtered to ensure the dissolved C0 2 level of the wine is not the result of microbial infection.
It is an important aspect of this invention that the recommended level of dissolved CO 2 will reduce the oxygen content of the wine whereby assisting with protecting the wine from oxidation during the transport of bulk wine from the winery to the aluminium container filler. This is particularly important because by preventing oxidation, minimal free S0 2 addition is required and minimum free S0 2 levels are maintained at the winery prior to dispatch.
The recommended level of dissolved CO 2 for wine is relevant as wine during transport is rarely refrigerated (eg. be it in ISO tankers-26,000 litres, Flexi tanks - 24,000 litres or road tanker transport -various compartmentalized/litreage volumes) consequently the temperature of the wine increases and the potential for yeast activity enhanced. During this transit time the wine is also susceptible to oxidation by extended contact with air via faulty seals and closures.
Additionally the dissolved C0 2 will prevent further oxidation of the wine caused by the effects of ullage (namely the gap - air in the headspace) created in any one particular tanker compartment by either under filling, evaporation or leakage of the wine during transit.
The levels of the actual C0 2 in the wine and resultant effectiveness will diminish as the temperature of the wine increases (during transport). However the initial level of dissolved C0 2 in the wine at the winery, ensuring that the wine will arrive at its destination in the same condition as when dispatched from the winery and with preferred final levels of dissolved C0 2 of 50 ppm - 1200 ppm for still white wines and 50 ppm to 400 ppm for still red wines prior to can filling.
The combination of microfiltration and lower free SO2 levels inhibits wine spoilage as the potential for oxidation, microbiological spoilage and re-fermentation are far greater during wine transport and wine transfer than in storage at the winery. The combination of maximum dissolved oxygen minimum dissolved carbon dioxide levels also assists. In addition, it is impossible to perform any corrective procedures during transit.
The recommended specific levels of dissolved CO2 in wine are essential in maintaining the wines varietal character.
The preferred range of dissolved C0 2 for still red wine is 50 ppm to 400 ppm more preferably 200 ppm to 400 ppm as higher levels will create a sharper more aggressive tannic tasting wine.
The preferred range of dissolved C0 2 for still white wines is 50 ppm to 1200 ppm (dependent on varietal character of the wine and the level of freshness and crispness required) and preferably is 400 ppm to 800 ppm..
Preferably the dissolved CO2 level at the winery and after wine transfer to tanker is 0.8 - 1.2g/L (800 ppm - 1200 ppm).
Preferably the dissolved CO2 in storage tank at filling facility prior to canning is up to 1.2g/L (1200 ppm). For still red wines this is preferably up to 0.4 g/L (400 ppm). This preferred maximum level will prevent significant loss of shelf life due to minimising oxidation potential during bulk wine transport and the resultant oxidation of the packaged product during storage and transport.
Table 11a. shows for red wine the effect of Dissolved Carbon Dioxide levels Table 11b. shows for white wine the effect of Dissolved Carbon Dioxide levels
Table 11a
5 * S0 2 levels measured at the time of filling
Table 11b
* S0 2 levels measured at the time of filling
With sparkling wines that have high CO 2 levels due to secondary fermentation (>6g/L) or carbonation (2-5 g/L) the control of DO levels is essential. Low Alcohol Wine/Wine Products
The preferred level of Sorbic Acid > 90mg/L protocol is recommended for low alcohol wines (i.e.<9% ALCA OL) due to the increased risk of viable yeast cells compared to > 9% ALCA OL wines and wines that have not undergone Malolactic fermentation (MLF). Should MLF occur in the wine in the aluminium container an unpleasant odour - geraniol (similar to Geranium) - will result. Due to the hermetically sealed environment as part of the exact equilibrium protocol in this patent required for the aluminium container for wine only minimal Potassium Sorbate addition is required. It is important to pay attention to pH, Free S0 2 and alcohol levels prior to the addition of Potassium Sorbate. Potassium Sorbate under this protocol is preferably used in small quantities in conjunction with potassium metabisulphite in sweet and semi-sweet wines to prevent secondary fermentation. When dissolved in water, Potassium Sorbate breaks down into Sorbic acid and ionic potassium.
This specification is recommended for still and sparkling wines (including fortified, sweet and semi sweet wines) and also wines mixed with mineral water, juice, flavours etc.
Table 12a. shows the organoleptic results for low alcohol red wine (<9%) and zero Sorbic Acid
Table 12b. shows the organoleptic results for low alcohol white wine (<9%) and zero Sorbic Acid
Table 12 a
Organoleptic
Results - low alcohol
wine
<9% alc/vol
Molecular Alc/vol PH
Sorbic Acid - 0 ppm S0 2 - mg/L initial 3 months 6 months 9 months 12 months
0.4 to 0.8 <9% 2.9
to
<3.5 Increased micro activity.
Clean Slight cloudy Micro issues Refermentation of Product. Product not Fresh appearance Blown cans. Spoiled fit for sale.
* S0 2 levels measurec at the time of filling
Table 2 b
Organoleptic
Results - low alcohol - wine
<9% alc/vol
Molecular Alc vol PH
Sorbic Acid - 0 ppm S0 2 - mg/L initial 3 months 6 months 9 months 12 months
0.4 to 0.8 <9% 2.9
to
<3.5
Increased micro activity.
Clean Slight cloudy Micro issues Refermentation of Product. Product not Fresh appearance Blown cans. Spoiled fit for sale.
* S0 2 levels measured at the time of fi ling
Table 12c shows Organoleptic results for low alcohol Carbonated Red wine (<9 ) and zero Sorbic Acid;
Table 12d shows Organoleptic results for low alcohol Carbonated white wine (<9%) and zero Sorbic Acid;
Table 12c
Organoleptic
Results - low alcohol
wine
<9% alc/vol
Molecular Alc/vol pH
Sorbic Acid - 0 ppm S0 2 - mg/L initial 3 months 6 months 9 months 12 months
0.4 to 0.8 <9% 2.9
to
<3.5 Increased micro activity.
Clean Slight cloudy Micro issues Refermentation of Product. Product not Fresh appearance Blown cans. Spoiled fit for sale.
* S0 2 levels measured at the time of fi ling Table 12d
Organoleptic
Results - low alcohol
wine
<9% alc/vol
Molecular Alc/vol pH
Sorbic Acid - 0 ppm S0 2 - mg/L initial 3 months 6 months 9 months 12 months
0.4 to 0.8 <9% 2.9
to Increased micro activity.
<3.5 Clean Slight cloudy Micro issues Refermentation of Product. Product not Fresh appearance Blown cans. Spoiled fit for sale.
* S0 2 levels measurec at the time of fi ling
Table 13a shows the organoleptic results for low alcohol Red wine (<9%) with addition of Sorbic Acid
Table 13b shows the organoleptic results for low alcohol white wine (<9%) with addition of Sorbic Acid Table 13 a
* S0 2 levels measured at the time of filling
The wine varieties listed below in table 14 are the wines utilized in the foregoing tables, however the invention is not limited to such particular wines, or specific style nor combination of varieties for which the varietal is selected. See below table of wines capable of being packaged using these protocols. This is a non exhaustive list:
Table 14.
Grape Variety used in these patented protocols
Cabernet Petit Verdot
Shiraz Pinot Noir
Merlot Tempranillo
Still Red Malbec Tannat
Grenache Gamay
Zinfandel Nebbiolo
Sangiovese Mataro
Chardonnay
. . _. Gewurtztraminer
Sauvignon Blanc
c ... Muscat
Semillon
„. .. Chenm Blanc
Still White Riesling
Pinot Gris , ,·
. Gruner Veltlmer
Cnasse as
' , ' . Verdelho
Colombard
Shiraz Durif
Sparkling
Pinot Noir Merlot
Red
Cabernet
Pinot Noir Macabeo
Pinot Meunier Xarel-lo
Sparkling Chardonnay Parellada
White Pinot Blanc Muller- Thurgau
Riesling Semillon
Sauvignon Blanc
Moscato
Most varieties as detailed in
Low alcohol
Table 13.- Pending style Muscat Blanc
requirements In this specification, reference to values for analytes in wine, gas composition, dimensions, volumes and pressure refer to the values as determined under standard laboratory conditions of 20°C unless the context provides otherwise. Since modifications within the spirit and scope of the invention may be readily effected by persons skilled in the art, it is to be understood that the invention is not limited to the particular embodiment described, by way of example, hereinabove.