AU2001100154A4 - Processing methodology - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT Applicant(s): CARLTON AND UNITED BREWERIES LIMITED A.C.N. 004 056 106 Invention Title: PROCESSING METHODOLOGY The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 PROCESSING METHODOLOGY The present invention provides a method of stabilising alcoholic beverages containing plant extracts.

So-called energy drinks containing caffeine have become very popular. However, in some countries it is not permissible to add caffeine directly to an alcoholic beverage. On the other hand, it is permissible to add plant extracts, for example, extracts of guarana as a herbal addition to beer whilst at the same time effectively adding natural caffeine to the alcoholic beverage.

Extracts of guarana and indeed other plant extracts, for example, extracts of herbs such as ginseng, cause haze, particularly in beer. The haze worsens following heat treatment such as pasteurisation. It also worsens as a result of storage.

Known treatments for removing haze from beer were trialed. These included the addition of proteolytic enzymes and silica gel. However, neither were successful.

Despite the failure of these known treatments, it was discovered that treatment with polyvinyl polypyrrolidone (PVPP) successfully reduced haze in beer without significantly affecting the organoleptic properties of the resultant beer.

Accordingly, the present invention provides a method of stabilising an alcoholic beverage containing a plant extract, the method comprising adding to an alcoholic beverage containing a plant extract, an effective amount of an adsorbent that is capable of adsorbing haze-forming components of the plant extract, and removing the adsorbent from the alcoholic beverage.

Preferably, the adsorbent is polyvinyl polypyrrolidone. Polyvinyl polypyrrolidone is a cross- 3 linked homopolymer of polyvinyl pyrrolidone. It is catalytically produced under conditions that result in polymerisation and cross-linking such that an insoluble polymer is produced.

The method of the invention is particularly suited to the production of beer containing extracts of guarana and/or other plant extracts such as extracts of ginseng. The plant extract may be added to beer before or after pasteurisation, but ideally before any final filtration of the beer. If the plant extract is added after the final filtration of the base beer, it is necessary to include a further filtration step after addition of the adsorbent.

Persons skilled in the art would appreciate that any plant extract which contains desirable properties may be used in the present invention. For example, guarana, yerba mate, ginseng, stearalia acuminate, cola acuminate, cola scemen, taraxaci radix, yohimbe and other such herbs may be utilised. It is well known by people skilled in the art that many of these herbs are members of the order celastrales, and so such members of this order have desirable properties which may be used in alcoholic beverage of the present invention.

The quantity of PVPP required to clear the haze from a beer containing guarana is at least 10 g/hL, but varies according to the type of guarana extract.

Similarly, the preferred level of PVPP additive depends very much on the guarana additive. For a guarana containing 5% caffeine derived from Nutrinova and added to beer so that the beer contains caffeine in the range from 70-80 mg/L, the optimum addition of PVPP is 25 g/hL. On the other hand, for guarana obtained from Bronson and Jacobs containing 2.5% caffeine and added to beer to provide a caffeine content in the range from 70-80 mg/L, the optimum quantity of PVPP required is 50 mg/hL.

Nutrinova and Bronson and Jacobs are suppliers of guarana extracts.

4 Caffeine imparts a bitter taste to beer to which it is added. If desired, the bitter taste may be counteracted by priming the beer. For example, priming a beer by 0.1 0 P is sufficient to counteract the bitter taste of caffeine in a beer containing 75 mg/L caffeine.

The following examples illustrate the invention.

Example 1 To more closely determine the optimum amount of PVPP required, a series of beers was prepared (PVPP contact time 10 minutes at 2 0 C, filtration using Cuno pasteurisation 25 PU): guarana PVPP Haze after Caffeine Polyphenols Polyphenols addition (g/hL) pasteurisation (mg/L) (Colourimetric)

(HPLC)

(mg/L) (units) A no 0 48 (blank) 150 71 B yes 0 760 76 198 88 C yes 50 150 78 141 87 D yes 100 70 73 132 44 E yes 150 60 75 116 86 From the haze results it is apparent that the ideal PVPP treatment level was about 100 g/hL. Caffeine was unaffected by PVPP.

The colourimetric procedure yields total polyphenol content, and does not give any indication of individual components.

Example 2 These same beers were also sent off to ISP (a PVPP supplier) in Singapore for challenge assessment of both polyphenols and proteins (PT testing) in order to determine the optimum stabilisation treatment regime by this alternative procedure: guarana PVPP (g/hL) Protein P40 Polyphenol T125 5 Values of less than 20 mL of Protein P40 reagent and/or less than 20 mL of Polyphenol T125 reagent per 100 mL of beer indicate that the beer is unstable and a haze is likely to form. The above results indicate that a level of 50 g/hL PVPP was sufficient to stabilise this beer.

Example 3 Guarana extract was added to beer (CD) to achieve mg/L caffeine. The beer was then primed (0.1 0 and sodium ascorbate was added (40 mg/L) to act as an antioxidant. Ginseng extract was also added. This beer was then subjected to two separate PVPP treatments g/hL and 100 g/hL) prior to filtration, packaging and pasteurisation. Samples were placed at 2 0 C, 30 0 C and for forced stability assessment.

PVPP Treatment 50 g/hL 100 g/hL Initial haze (FTU) after treatment, and 30 pasteurisation Initial caffeine (mg/L) 73 71 Haze after 5 days 50 0 C 50 Haze after 2 weeks 30 0 C 35 Flavour after 2 weeks 30 0 C little change little change Haze after 4 weeks 30 0 C 40 Flavour after 4 weeks 30 0 C acceptable acceptable Caffeine after 4 weeks 30 0 C 70 68 Haze, flavour after 6, 8 and 12 weeks 30 0 C results to came 6 These results showed that a PVPP treatment of g/hL was sufficient to stabilise the final beer. This agrees well with the ISP findings.

These beers will be assessed again for flavour and haze stability after 6, 8 and 12 weeks storage at (note that 12 weeks at 30'C is equivalent to about 6 months storage at ambient temperature). From these initial results it is apparent that with the correct initial PVPP treatment the beer is quite physically stable, and long term flavour stability may be good as well.

Example 4 Subsequent to the stabilisation work, two further samples of guarana extract were obtained. These were extracts containing 5.0% caffeine (Nutrinova) and caffeine (Bronson Jacobs). Initial work (without

PVPP

treatment) showed that the new Nutrinova product appeared to be even better than the original B J caffeine) product. The alternative Bronson Jacobs caffeine) product was not at all suitable due to it being poorly soluble in beer, and hard to handle (extremely viscous).

It contains a lot more plant material than the other two extracts, indicating a difference in extraction methodology.

guarana addition A none B B J 2.506 caffeine product C B J 9.0% caffeine product D Nutrinova 5.0% caffeine product Haze before pasteurisation

(FU)

30 visually clear >1100 fine thick haze 800 large floating chunks 220 very faint haze Haze after pasteurisation

(FTU)

30 visually clear >1100 fine thick haze >1100 large floating chunks 200 very faint haze Caffeine (mg/L) (blank) 72 66 7 Based on the above results it was decided to use a much lower PVPP rate (25 g/hL) for the Nutrinova extract than that used for the work with the original Bronson Jacobs extract. Extract dosing was increased to 0.250% v/v to account for the fact that this extract appeared to contain only 3.0% caffeine based on our analysis (or only recovery of caffeine in beer). Samples were prepared and assessed as before, as shown in the following table: Caffeine (mg/L) 72 Initial haze (FT) pre-treatment 175 PVPP treatment 25 g/hL Initial haze (FTU) post treatment Initial haze (FTU) post treatment, after pasteurisation Initial flavour OK Haze after 5 days 500C Flavour after 5 days 50°C no abnormal character Haze, flavour after 2 weeks 30 0 C 35 FTu, little change Haze, flavour after 4, 6, 8 and 12 weeks 30 0 C results to cane Initial indications are thus very good.

Claims (9)

1. 2. A method according to claim i, wherein the adsorbent is a cross-linked homopolymer.
2. 3. A method according to claim 2, wherein the homopolymer is polyvinyl polypyrrolidone.
3. 4. A method according to any one of claims 1 to 3, wherein the alcoholic beverage is beer. A method according to any one of claims 1 to 4, wherein the plant extract is selected from the group consisting of guarana, yerba mate, ginseng, stearalia acuminate, cola acuminate, cola scemen, taraxaci radix, yohimbe or other caffeine-containing plant extract.
4. 6. A method according to any one of claims 1 to wherein the plant extract is added to the alcoholic beverage before or after pasteurisation.
5. 7. A method according to claim 6, wherein the plant extract is added to alcoholic beverage before final filtration.
6. 8. A method according to any one of claims 1 to 7, wherein the absorbent is PVPP and is at least
7. 9. A method according to any one of claims 1 to 8, wherein the alcoholic beverage is beer as the beer is primed by 0.1'p. An alcoholic beverage produced by a method according to any one of claims 1 to 9.
8. 11. An alcoholic beverage containing a plant extract, wherein said plant extract is stabilised using an -M 9 adsorbent that is capable of adsorbing haze-forming components of the plant extract.
9. 12. A method according to claim 1 substantially as hereinbefore described with reference to any one of the examples. Dated this 13th day of July 2001 CARLTON AND UNITED BREWERIES LIMITED By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia