The general art of brewing beer or ale is well established both on a large commercial scale and on a"home brew"scale.

Ale was first brewed with malted barley and a flavoured preservative such as nettles. As the art procressed hops took over as the preferred preservative and product became known as"beer". It is generally understood that grain is the fermentable base material of anything called beer or ale.

Hops not only provide preservative qualities, it also gives a distinctive flavour, bitterness and aroma.

The use of hops, historically, kept the beer from"going off" over the summer months. Quality ales, made from ingredients with lesser preservative qualities, were protected by a high alcohol content.

The art of brewing and producing new brews is a time consuming process requiring a high degree of experimentation and thought. The novelty in the present invention lies in an ingredient that provides a unique taste and may even replace hops, thereby producing a surprising result. The novel ingredient is commonly known in New Zealand as Manuka (Leptospermum Scoparium).

SUMMARY OF THE INVENTION The object of the invention is to produce a uniquely tasting ale. This object has been achieved by utilising Manuka in a brewing process.

In one broad aspect the invention is defined as the use, in the brewing of ale or beer, of species Leptospermum as an ingredient in admixture with other ingredients.

Preferably the variety of Leptospermum is scoparium.

In a second broad aspect of the invention there is provided a method of brewing an ale or beer including the step of adding a quantity of manuka at a stage of the brewing process when the brew is subjected to elevated temperature.

In a third broad aspect of the invention there is provided a method of brewing an ale or beer including the step of preparing a manuka syrup by boiling a quantity of manuka in water and combining the syrup with mashed malts for a boiling stage of the brewing process.

The invention thus provides a uniquely tasting ale.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic diagram of a process for home brewing an ale according to the present invention, and Figure 2 is a schematic diagram of a process for commercial brewing of an ale according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

It will be appreciated by those skilled in the art that alternative brewing processes may be employed that still fall within the scope and spirit of the invention as it is intended.

A suggested"recipe", for producing an ale according to the present invention, for home brew use, to produce a batch of 25 litres of 4% alcohol by volume (original gravity 1. 038 to 1. 040) ale includes : 4kg English Pale Malt * 250g Crystal Malt 180g dried Manuka brush (clippings)-90g early boil, 90g late boil Ale Yeast zig Irish Moss, 5g Gelatine (Fining) 2. 5g Magnesium Sulphate, 5g Calcium Sulphate (Water treatment) Sodium Metabisulphite (Sterile solution) * White Sugar (for bottle carbonation only) Water The above ingredients, with the exception of the manuka, will be familiar to those skilled in the art. It should be noted

that different varieties of manuka will have an effect on the strength of bitterness.

All equipment described hereinafter must be sterile and clean prior to use and ongoing cleanliness should be maintained during the brewing process.

To prepare the water, 20L of fresh water is adjusted to a pH level of 5-5. 3. Calcium sulphate is added for pH adjustment.

With reference to Figure 1, the brewing method is as follows.

Firstly, the 20L of treated water (liquor) is boiled for 10 minutes, allowed to cool and then transferred to a Mash tun A. Approximately 18L of treated liquor will be"racked off" during the transfer leaving 2L of hard water to be discarded.

"Racking off"is understood as the act of transferring liquids, while leaving behind sediment at the bottom of a vessel.

At A the liquor is heated to 72°C (known as the"strike heat"). Cracked Malt is added and stirred in to distribute and the temperature adjusted as quickly as possible to 65°- 68°C. The"mashing"process lasts for 2 hours at 65°-68°C,

stirring occasionally to ensure even temperature distribution. Enzyme activity is maintained.

The liquor mixture, now known as"wort", is then sparged with 8-10 litres of liquor at 72°-76°C. Sparging is the act of flushing out valuable sugars from the grains after mashing, in the mash tun A.

The sparge should end when the specific gravity is 1. 005 to 1. 010.

Magnesium sulphate is now added as the wort is transferred to copper boiler (kettle) B after settling (may take 20 minutes or more). Spent grain is removed as indicated by arrow 1.

Wort within kettle B is then raised to a vigorous boiling temperature. Once boiling, 90g of manuka brush, preferably contained in a muslin bag for convenience, is added. About 2 litres of liquid volume will be lost due to the boiling process.

This process lasts llK hours, stirring at intervals.

At approximately 20 minutes before the end of the boil, the remaining 90g of manuka brush in muslin bag may be added (late boil manuka brush) together with the Irish moss.

After the boiling process within kettle B, the wort stands so that trub may settle (this may take 30 minutes or more).

Trub is undesirable protein matter precipitated from the boil. Trub and spent manuka removal is indicated by arrow 2.

Wort is then transferred to fermentation vessel D via a heat exchanger (copper coil) C. The wort is rapidly cooled (to drop further protein matter out of the solution) in the copper coil C to 20°-22°C before being transferred to fermentation vessel D. Sterile water (liquor) is added to make up to original gravity of 1. 038 to 1. 040 for approximately 25 litres.

Ale yeast is added (called pitching') to vessel D when the wort is at its original specific gravity and temperature is 20°-22°C. The wort is then oxygenated by vigorous stirring (rousing).

Vessel D has a loose lid to allow the yeast to breathe as it requires oxygen at this stage.

The overall fermentation process within vessel D should last 7 days (with temperature maintained at 16°-20°C, preferably 18°C) before subsiding. When fermentation does subside the "green ale" (as it is now known) should be racked into settling vessel E. Discarded dead yeast is indicated by arrow 3.

Settling vessel E includes an air lock where the ale should drop to a specific gravity of between 1. 008 and 1. 010. The gelatine is then added to"fine" (clarify) the ale.

When clear, the ale is racked into maturing vessel F.

Removal of sediment after"fining"is denoted by numeral 4.

The ale generally resides in maturing vessel F (airtight) for 10 days. 500mL of weak solution (lOg per litre) sodium metabisulphite can be added to protect the green ale.

However, generally if the ale is contained in controlled, sterile conditions then the qualities of manuka and alcohol should protect the ale.

The ale is then bottled, with the addition of 8-12g of white sugar per 750mL bottle for priming. Each bottle G is capped airtight.

Preferably bottle G is left for conditioning and final maturing for three weeks or more at 13°C in a dark room.

Finally, the ale is ready to drink from glass H. Ideally the ale is served chilled at 8°-12°C.

The above process is subject to many variations depending on the requirements of the brewer.

The process is capable of being scaled up into commercial production known to the art. The differences between commercial and home brewing are well known and the use of manuka generally only affects the boiling stage. Other operations are generally the same. An example of scaled up' production is described hereinafter with reference to Figure 2.

Ingredients for a commercial brew'of 350L (can be scaled up to 1200L) @ 4. 5% alcohol are suggested as follows :

58. 8 kg English Pale Malt 3. 64 kg Crystal Malt 2. 52 kg Manuka Brush (1. 26kg early ; 1. 26 kg late boil) 45 g Calcium Sulphate 30 g Magnesium Sulphate 70 g Irish Moss 144 g Gelatine 70 g English Ale Yeast Strain NA Sodium Metabisulphite 10% stock solution 5mL.

Enough clean fresh water will be required to mash the above grist effectively ("grist"referring to the malt ingredients). 2. 4 litres of water is recommended per kilogram which corresponds to 150 litres of water. Water should be boiled for 15 minutes prior to use.

Firstly, referring to Figure 2, assume that all equipment is sterile and clean.

The malt grist grains are passed through a mill J to crack grains enough to allow liquor (water) to be able to penetrate husk.

The mash tun K liquor is treated with 45g of Calcium Sulphate to aid starch conversion and resist bacterial attack. This requirement may change depending on the quality of the local water supply.

The liquor temperature is raised to 72°C. The grist 5 is introduced to the mash tun K and the liquor and is stirred in. The mash is reduced to 66°C (a 3°C tolerance is acceptable) as quickly as possible and now maintained at this temperature for 2 hours to convert starch to sugars.

Sparge tank L holds a quantity of water at 74°C. When mash is finished it is allowed time to settle.

When mash is completed, runnings 6 from mash tun K are taken to a boiler M. When mash stops running, sparge tank L begins spraying water (liquor) over the spent mash and runnings are checked until the gravity is in the region of 1. 010-1. 005. Sparging then stops, allowing no further liquor to enter the boiler M, as unwanted protein matter will enter. The mash grains are discarded as denoted by arrow 7.

It is important not to let the temperature of runnings drop below 60°C as cloudiness in ale may result.

The boiler M is topped up with very hot liquor to a manageable level and is rapidly brought to the boil. (Not more than 350 litres). Before the boil starts 35g of magnesium sulphate (epsom salts) is added to help the boil stability and encourages further precipitation of hot break.

When boil is underway manuka brush is added in a stainless steel grill container 8. Only 1. 4kg of the brush is added at this stage.

The boil should be as vigorous as possible to achieve a good hot-break (unwanted protein matter excreted out of solution at very hot temperature). The boil needs to be at least 11r hours. 20 minutes from the end of the boil the other 1. 4kg of manuka brush is added into the stainless steel grilled container 8 and 70g of Irish Moss is added to aid clearing after the boil.

The boiler M is turned off and allowed to settle. The manuka container 8 is taken out of the boiler M. The boiler contains a stirrer 9 and this is now rotated creating a whirlpool where the wort 10 is able to be separated from the trub 11 (unwanted matter). The wort 10 is now passed through

a heat exchanger N to rapidly cool the wort 10 down so a cold break occurs. A loss of about 40-50 litres is discarded from the boiler as trub 11. The Manuka Brush is also discarded.

After passing through the heat exchanger N wort 10 enters the first fermentation tank O. Gravity Readings are taken and the original gravity adjusted to 1. 043 by adding sanitised liquor. This brings the fermenter to approximately 300L (depending on mash conversion, boiler evaporation loss, trub loss etc).

The temperature is taken and the gravity reading for excise duty temperature should preferably be around 20-21°C. The yeast is pitched and aerated vigorously to aid yeast budding.

The first fermenter 0 is an open tank (i. e., lid not sealed) and primary fermentation should be vigorous and robust. Hydrometer readings should monitor the progress of the fermentation.

Pumps (not illustrated) are employed to move the wort 10 from vessel to vessel. The heat exchanger should have dropped the temperature to 40-45°C and adding extra (water) liquor to the required final gravity should bring the temperature to 20-

21°C. The ideal working temperature of the fermentation is to be maintained at 18°C and held there by external cooling refrigeration coils around the outside jacket of the fermenting vessel 0. Similar cooling coils are used to reduce the temperature at racking gravity of the secondary fermenting vessel P to stop the yeast working below its working temperature of 15°C-22°C.

Attenuation progress (drop in specific gravity of the wort in progress over time) is monitored to determine when the wort goes from aerobic (utilising air) to anaerobic (does not require air) by viewing the surface of the fermentation.

This is 2-3 days after yeast is pitched.

The wort 10 can now be transferred to the secondary fermentation vessel P gently without uptake of air into the wort. The vessel P has been purged with CO2 (carbon dioxide gas) prior to this operation ensuring a protective blanket of gas to the wort. A lid is fitted to seal against the outside atmosphere.

The vessel P has a pressure release valve to vent off excess C02 (set to known limits). Fermentation continues at 18°C until racking gravity is reached. Racking gravity will be

1. 013-1. 014 and final gravity will be 1. 009. The temperature is dropped to 10°C. The lid is vented slightly at this time. Wort is protected by the C02 blanket.

Most yeast drops from the solution but enough is left to work on the unused sugars (to bring ale into condition at 1. 009- 1. 014).

The lid is released and the"green ale"12 is racked very carefully without gaining air into maturation vessel Q. 5mL of a 10% stock solution of sodium metabisulphite for the 300L brew is mixed in gently to sterilise against infection. The maturation vessel Q is closed to the atmosphere. There is an over pressure release valve for excess pressure (pre-set limits).

Total maturing is recommended as 21-22 days. For the first 8 days the temperature is 15°C. Over the next 12 days the temperature is progressively dropped towards +2°C. Carbon dioxide gas absorbs into solution. Undesirable volatiles are released out of solution, the ale clears of yeast and other protein matter.

A carbon dioxide cylinder is (after 8 days) slightly pressured on top of the maturation ale vessel. As the temperature is lowered CO2 gas is absorbed into solution and the pressure needs to be maintained otherwise the vessel will buckle inwards under suction from the CO2 going into solution.

The room atmosphere is preferably 0-2°C when the lid is opened to the atmosphere under C02 blanket. Gelatine at the rate of 144g to 300L brew is added for fining. The gelatine should be pre-mixed with 2-3 litres of hot water (not boiling). When clear and cool it is mixed gently into the ale.

Then the lid is closed and the temperature reduced to 0- 1°C. The ale clears ready for racking via a pump in approximately 48 hours through a coarse membrane filter R. Filter R will allow some yeast cells through (although visually clear) but will give the ale a"polish"as it is transferred to the bright tank S.

The bright tank S is purged with C02. Some C02 will be lost out of solution across the membrane filter R. The CO2 bottle over the bright tank S also adds pressure when the ale is

bottled from the bright tank S to kegs or bottles. Again, the volume of empty space needs to be replaced with C02 gas otherwise the vessel can collapse inwards under vacuum from the lost ale (during bottling).

The ale can be gravity fed from the vessel S into conventional bottling machinery (not illustrated).

The bottling room should be at 0-5°C so as to reduce the loss of C02 prior to capping.

The bottled ale 13 is labelled and put in cartons ready for delivery and sale. Preferably, bottles 13 are held for 8-10 days to bed in, in the bottle, which is the final conditioning. They are held at 13°C to aid this in storage (preferably in the dark).

The above process incorporates a variety of equipment familiar to many known brewing processes and is meant by way of example only. The ale of the present invention may also be produced from a continuous process as opposed to the batch process described.

It is also understood that such equipment must be maintained to a high standard of hygiene.

A yet further proportional (i. e. can be scaled up accordingly) method to brew 10 litres of ale includes :- * 90g Manuka brush # 1. 6kg English Pale Malt 90g Crystal Malt Firstly, the 90g manuka brush is boiled in 5. 5L of clean fresh water for 1 hours. Brush is discarded and liquid saved leaving 2 to 3L of manuka syrup.

Malts are mashed at 65-68°C in 5. 5L of water and then sparged with 3L of water at 72°C. Grains are discarded.

Both syrup and malt are transferred to a boiler and raised to boiling for 1 hours, rapidly cooling to 21°C thereafter.

Specific gravity is measured. Volume should be close to 10L.

Pitch yeast and ferment out as normal.

This basic method can be scaled up accordingly and gives a remarkably similar result to the previous methods.

The manuka brush used in the foregoing processes is preferably finely chopped and lightly dried to remove moisture and stop spoilage. In the commercial process described, the twiggy brush of a manuka plant is preferable to leaf. Sole use of the leaf will cause the ale to be too bitter.

Manuka brush wood has a distinctive sweet taste that is transferred to the ale. The majority of the taste comes from pia manuka', a white sticky substance which exudes from the bark. The ale's bitterness then extends from the tannins in the leaf. There is therefore a fine balance in the recipe of brush that does not have"too much"leaf on it. Combined, the ale is provided with a delicate sweet taste and unique colour.

Furthermore, the present invention is a true ale, i. e. not brewed with hops and malted barley as the sugar base.

Similar malts to English Pale Malt may be used to provide similar tastes, i. e. Lager Malt.

Manuka, as used in the process described, has surprisingly been found to offer :

bittering enhancement * clean finish and clarity * anti-bacterial properties pale copper gold colour # distinctive manuka aroma # distinctive and pleasant taste # preservative qualities Substituting manuka for hops as used in conventional beer brewing results in a uniquely tasting ale in addition to the other advantages outlined above.

Ale produced by the process described has met with positive feedback from taste-testing trials indicating a significant potential market for"Manuka Ale".