Title of Invention

A GREEN LEAF PRODUCT AND A PROCESS FOR THE MANUFACTURE THEREOF

Abstract

A palatable green leaf tea from Camellia sinensis var. assamica is disclosed. Infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C produces a beverage comprising catechins in an amount of between 0.01 and 0.1% by weight of the beverage. Also disclosed is a process for manufacturing the leaf tea product wherein fresh leaf from var. assamica is macerated using a combination of a rotorvane and double-cone processor.

Full Text

FORM - 2 THE PATENTS ACT, 1970 (39 of 1970) & The Patents Rules, 2003 COMPLETE SPECIFICATION (See Section 10 and Rule 13) A LEAF PRODUCT AND A PROCESS FOR THE MANUFACTURE THEREOF HINDUSTAN UNILEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India The following specification particularly describes the invention and the manner in which it is to be performed WO 2008/040627 PCT/EP200 7/059709 - 1 - A GREEN I£AF TEA PRODUCT AND A PROCESS FOR THE MANUFACTURE THEREOF Technical Field of the Invention 5 The present invention relates to green leaf tea. Background of the Invention Green tea is a popular beverage which has been consumed in China and Japan for many hundreds of years. Recently, extensive 10 laboratory research and epidemiologic studies have shown that compounds present in green tea (particularly the flavanols such as catechins) may reduce the risk of a variety of illnesses. These studies, along with the increasing complexity of the consumer's palate have led to increased consumption of green tea, 15 even in markets (such as the USA and Western Europe) where there is no tradition of green tea consumption. There are two varieties of the tea plant Camellia sinensis, namely var. sinensis and var. assamica. The variety Camellia 20 sinensis var. assamica typically has the highest catechin content and is also relatively rich in certain non-flavanol actives, such as the amino acid theanine. The flavanols have a large influence on the bitterness and 25 astringency of tea infusions. Thus, owing to the high flavanol content of var. assamica, infusions of green tea from this variety are found to be unpalatably bitter. Consequently, var. assamica is considered unsuitable for use in green tea production (see, for example, "Tea: Cultivation to Consumption", K.C. 30 Willson and M.N. Clifford (Eds), 1st Edn, 1992, Chapman & Hall (London), Chapter 13, p. 414). WO 2008/040627 PCT/EP2007/0S9709 - 2 - We have recognised that there is a need to provide a green leaf tea that has the enhanced levels of actives typical of var. assamica but which produces a beverage having the palatability of traditional green tea beverages prepared from var. sinensis. We 5 have found that such a need may be met by controlling the amount of catechins delivered by the green leaf tea. Summary of the Drawings Figure 1 shows an elevation of the rotor of a double-cone 10 processor. Figure 2 shows a vertical section of the barrel of a double-cone processor. 15 Tests and Definitions TEA "Tea" for the purposes of the present invention means material from Camellia sinensis var. sinensis and/or Camellia sinensis var. assamica. 20 "Leaf tea" for the purposes of this invention means a tea product that contains tea leaves and/or stem in an uninfused form, and that has been dried to a moisture content of less than 30% by weight; and usually has a water content in the range 1 to 10% by 25 weight (i.e. "made tea"). "Green leaf tea" refers to substantially unfermented leaf tea. "Fermentation" refers to the oxidative and hydrolytic process that tea undergoes when certain endogenous enzymes and substrates are brought together, e.g., by mechanical disruption of the cells by maceration of the leaves. 30 During this process colourless catechins in the leaves are converted to a complex mixture of yellow and orange to dark-brown polyphenolic substances. WO 2008/040627 PCT/EP20077059709 - 3 - ""Fresh tea leaves" refers to tea leaves and/or stem that have never been dried to a water content of less than 30% by weight, and usually have a water content in the range 35 to 90%. 5 BEVERAGE As used herein the term "beverage" refers to a substantially aqueous drinkable composition suitable for human consumption. PRODUCTION OF A BEVERAGE BY INFUSION OF 2 g LEAF TEA IN 200 ml 10 WATER AT 90°C FOR 1.5 MINUTES For the purposes of this invention, the ability of leaf tea to deliver actives such as catechins, caffeine and/or theanine, as well as the ability of the leaf tea to deliver beverages with good colour and/or clarity is determined using the following 15 standard infusion conditions: 1. The leaf tea is removed from any package and 2 g is placed in a 500 ml container. 2. 1 litre of deionised water is then brought to boiling and 200 20 g immediately added to the 500 ml container. 3. The container is stored at an air temperature of 20°C and the leaf tea is allowed to statically infuse in the water. 4. After 1.5 minutes, the infusion is stirred for 5 s by hand using a spoon and the leaf tea is then immediately removed from 25 the infusion by straining the contents of the container through muslin. CATECHINS As used herein the term "catechins" is used as a generic term for 30 catechin, gallocatechin, catechin gallate, gallocatechin gallate, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, and mixtures thereof. WO 2008/040627 PCT/EP200 7/059709 - 4 - DETERMINATION OF CATECHINS AND CAFFEINE IN LEAF TEA The amounts of catechins and caffeine in leaf tea are determined simultaneously by reverse-phase HPLC as follows: 5 Sample Preparation 1. Grind leaf tea using a Cyclotech™ 1093 sample mill (FOSS Ltd, Warrington, Cheshire, UK) fitted with a 1.0 (im screen, until a fine powder is achieved. 2. Weigh accurately approximately 200 mg of the ground leaf tea 10 into an extraction tube, and record the mass. 3. Warm at least 20 ml of a methanol-water solution (70% v/v methanol in distilled water) to 70°C. 4. Add 5 ml of the hot methanol-water solution to the extraction tube. Gently mix the methanol-water and leaf tea on a vortex 15 mixer; place in a water bath at 70°C for 5 minutes; mix again and then place in a water bath at 70°C for a further 5 minutes. 5. Gently mix the methanol-water and leaf tea on a vortex mixer again and then allow to cool for 10 minutes at an air temperature of 20°C. 20 6. Centrifuge the extraction tube at a relative centrifugal force (RCF) of 2900 g for 10 minutes. 7. The extraction tube should now contain a liquid supernatant on top of a plug of tea material. Carefully decant supernatant into a clean graduated test tube. 25 8. Add 5 ml of the hot methanol-water solution to the plug in the extraction tube. Gently mix the methanol-water and tea material on a vortex mixer; place in a water bath at 70°C for 5 minutes; mix again and then place in a water bath at 70°C for a further 5 minutes. 30 9. Gently mix the methanol-water and tea material on a vortex mixer again and then allow to cool for 10 minutes at an air temperature of 20°C. WO 2008/040627 PCT/EP2007/059709 - 5 - 10. Centrifuge the extraction tube at $ RCF of 2900 g for 10 minutes. 11. The extraction tube should now contain a liquid supernatant on top of a plug of tea material. Carefully decant supernatant 5 into the graduated test tube containing the supernatant from step 7. 12. Make up the pooled supernatants to lo ml with the methanol- water solution. 13. Add 1 ml of a solution of 2.5 mg/ml EDTA and 2.5 mg/ml 10 ascorbic acid in distilled water to the graduated test tube. 14. Dilute 1 part of the pooled supernatant mixture with 4 parts (by volume) of 10% acetonitrile stabiliser solution (10% v/v acetonitrile, 0.25 mg/ml ascorbic acid end 0.25 mg/ml EDTA in distilled water). 15 15. Decant the diluted pooled supernatant mixture into microcentrifuge tubes and centrifuge in a bench top centrifuge at a RCF of 14000 g for 10 minutes. HPLC Analysis conditions 20 Column: Luna Phenyl hexyl 5(1, 250 x 4.60 mm Flow rate: 1 ml/min Oven temperature: 30°C Solvents: A: 2% acetic acid in acetonitrile 25 B: 2% acetic acid and 0.02 mg/nu EDTA in water Injection volume: 10 |Xl WO 2008/040627 PCT/EP2007/059709 - 6 - Gradient: Time % Solvent A % Solvent B 95 Step 0 to 10 min 5 Isocratic 10 to 4 0 min 5-18 95 - 85 Linear gradient 40 to 50 min 18 82 Isocratic 50 to 55 min 50 50 Wash 55 to 75 min 5 95 Isocratic Quantification: Peak area relative to a calibration curve 10 constructed daily. Calibration curve is constructed from caffeine and the concentration of catechins is calculated using the relative response factors of the individual catechins to caffeine (from the ISO catechin method - ISO/CD 14502-2}. Individual caffeine standards (Sigma, Poole, Dorset, UK) are used as peak 15 identification markers. 20 25 DETERMINATION OF CATECHINS AND CAFFEINE IN A BEVERAGE The amounts of catechins and caffeine in a beverage are determined simultaneously by reverse-phase HPLC as follows: Sample Preparation 1. 9 ml of the freshly-brewed beverage are taken and 1.12 ml of acetonitrile added, along with 1.12 ml of a solution of 2.5 mg/ml EDTA and 2.5 mg/ml ascorbic acid in distilled water. 2. The resulting solution is then decanted into microcentrifuge tubes and centrifuged at a RCF of 14000 g for 10 minutes. HPLC Analysis conditions The HPLC analysis conditions are identical to those given above 30 for the leaf tea. WO 2008/040627 PCT/EP2007/059709 - 7. - DETERMINATION OF THEANINE IN A BEVERAGE The amount of theanine in a beverage is determined by reversed phase HPLC chromatography using fluorimetric detection following post-column derivatisation with o-pthalaldehyde. 5 Sample Preparation The freshly-brewed beverage is diluted with de-ionised water (25°C) in a weight ratio of beverage:water of 1:10. 10 HPLC Analysis conditions Column: Hypersil HyPURITY Elite™ C18, 5u, 150mm x 4.6cm Flow rate: 1 ml/min Oven temperature: 35 °C 15 Solvents: A: 5 mM pentadecafluorooctanoic acid in water B: 5 mM pentadecafluorooctanoic acid in acetonitrile Gradient: Time (min) 20 0 8 10 11 14 25 15 31 % Solvent A % Solvent B 85 15 85 15 80 20 10 90 10 90 85 15 85 15 Quantification: The eluant from the column is fed into a low dead-volume 3-way junction and mixed with the o-Pthalaldehyde 30 reagent in a 1:1 ratio, the o-Pthalaldehyde reagent being pumped at 1 ml/minute by the isocratic pump. (The o-Pthalaldehyde reagent is 1.0 g/1 o-Pthalaldehyde, 5 ml/1 methanol, 2 ml/1 Brij 35 and 3 ml/1 2-mercaptoethanol in pH 10 borate buffer.) WO 2008/040627 PCT/EP200 7/059709 - 8 - Fluorescence detection is: Excitation = 340 nm and Emission = 425 nm. Peak area relative to a calibration curve constructed daily is used for quantification. The calibration curve is constructed from dilutions of a standard solution of Suntheanine™ (Taiyo 5 KK) . DETERMINATION OF HAZE OF A BEVERAGE The haze of a beverage is measured at 25°c. Directly following infusion, the freshly-brewed beverage is allowed to cool to 25°C 10 and then immediately analysed using a Hach 21OOP turbidimeter (Hach Lange Ltd, Salford, UK) . The 2100P is a portable turbidimeter with a tungsten filament lamp as an optical light source. Sample volume is 15 ml. The cell path length is 2 cm. Haze is reported as NTU (Nephelometric Turbidity Units). 15 DETERMINATION OF COLOUR OF A BEVERAGE The colour of a beverage is measured at 2.5°C. Directly following infusion, the freshly-brewed beverage is allowed to cool to 25°C and then immediately analysed using a Minolta CT-310 20 transmittance color meter. The colorspaQe used is CIELab, the illuminant is C, and the cell path length is 10 mm. The meter is zeroed on distilled water and calibrated using a Yellow 101 filter (available from Lee Filters, Andcjver, UK) having: L* = 91.44, a* = -15.92, b* = 102.38, C* = 103.61 and h* = 98.84; 25 wherein L* is light-dark, a* is red-green, b* is yellow-blue, C* is chroma and h* is hue. PARTICLE SIZE For the purposes of the present invention, particle size is 30 characterised by sieve mesh size using the following convention: • Tyler mesh sizes are used throughout. WO 2008/040627 PCT/EP2007/059709 - 9 - • A "+" before the sieve mesh indicates the particles are retained by the sieve. • A "-" before the sieve mesh indicates the particles pass through the sieve. 5 For example, if the particle size is described as -5 +20 mesh, then the particles will pass through a 5 mesh sieve (particles smaller than 4.0 mm) and be retained by a 20 mesh sieve (particles larger than 841 um) . 10 ROTORVANE ■ A rotorvane is a type of tea leaf conditioner, conventionally used to wound tea leaves prior to processing with a CTC (crush, tear and curl) machine during black tea manufacture. Rotorvanes 15 are widely used in the tea industry and are described, for example, in "Tea: Cultivation to Consumption", K.C. Willson and M.N. Clifford (Eds), 1st Edn, 1992, Chapman & Hall (London), Chapter 14, especially pp. 486-487. Suppliers of rotorvanes include Vkram India Ltd (Kolkata, India) and Plamac (India) Pvt 20 Ltd (Kolkata, India). DOUBLE-CONE PROCESSOR A double-cone processor is a type of continuous tea leaf rolling machine. Double-cone processors are available, for example, from 25 Plamac (India)j Pvt Ltd (Kolkata, India). The double-cone processor is similar to the tea processing machine disclosed in UK patent GB 1 175 559 (Peter John Parr), except that the barrel and rotor shaft are modified as shown in 30 Figures 1 and 2, respectively. Specifically, the double-cone processor comprises a stationary barrel (10) having three sets of resistors (11) projecting from the inner wall of the barrel (10), an opening (12) near one end (feed end) of the barrel (10) to WO 2008/040627 PCTYEP200 7/059709 - 10 - feed fresh tea leaves to be macerated, and a rotor shaft (1) adapted to advance the tea leaves from the feed end to the other end (discharge end) of the barrel (10) by axial rotation therein and simultaneously macerate the leaves. The rotor (1) comprises a 5 helical feed worm (2) for part of its length near the feed end of the barrel (10), a first frusto-conical member (3) extending from the feed worm (2) and extending towards the discharge end of the barrel, and a second frusto-conical member (4) extending from the first frusto-conical member (3) to the discharge end of the 10 barrel (10) . The first frusto-conical member (3) has three sets of vanes (3A) radially projecting thereform, the vanes (3A) being staggered in relation to the resistors (11) of the barrel wall. The second fxrus to-conical member (4) has its inclined surface fluted with flutes (4A) helically disposed. The discharge end of 15 barrel (10) is fitted with a pressure sleeve (13) similar to the sleeve disclosed in GB 1 175 559, the sleeve having a plurality of studs (13A) projecting from its inner surface. Summary of the Invention 20 In a first aspect, the present invention provides a green leaf tea from Camellia sinensis var. assamica, wherein infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C produces a beverage comprising catechins in an amount of between 0.01 and 0.1% by weight of the beverage. 25 We have found that such a leaf tea can be used to prepare beverages at least as palatable as green tea beverages prepared from var. sinensis. 30 We have also found that a particularly convenient method of producing green leaf tea from Camellia sinensis var. assamica, which has the desired infusion properties, is by macerating fresh WO 2008/040627 PCT/EP200 7/059709 - 11 - leaf with the combination of a rotorvane and a double-cone processor. Thus in a further aspect, the present invention provides a 5 process for manufacturing a green leaf tea comprising the steps of: (a) providing fresh tea leaves from the plant Camellia sinensis var. assamica; then (b) heat-treating the fresh leaves to arrest enzyme 10 action; then (c) macerating the fresh leaves with a rotorvane and a double-cone processor, preferably by passing the fresh leaves through the rotorvane to produce partially macerated leaves and then passing the partially 15 macerated leaves through the double-cone processor to produce the macerated leaves; then . (d) drying the macerated leaves; and then (e) optionally sorting the dried macerated leaves according to particle size. 20 The present invention also provides green leaf tea obtained and/or obtainable by the process of the invention. In a further aspect still, the present invention relates to a new 25 leaf tea having enhanced levels of actives and/or good colour and clarity but having catechin levels typical of traditional green tea. Thus, the invention provides a green leaf tea from Camellia sinensis var. assamica and/or sinensis wherein infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C produces a 30 beverage comprising catechins in an amount of between 0.01 and 0.1% by weight of the beverage, more preferably between 0.04 and WO 2008/040627 PCT/EP2007/059709 - 12 - 0.09% by weight of the beverage, most preferably from 0.06 to 0.085%.; and wherein the beverage additionally: - comprises theanine in an amount of at least 0.004% by weight of the beverage, preferably from 0.005 to 0.02%, 5 and/or - has a haze of less than 20 NTU, preferably from 1 to 15 NTU, and/or - has a hue (h*) of between 103 and 115, preferably between 104 and 110, and/or 0 - has a chroma (C*) of between 6 and 15, preferably between 8 and 10, and/or - has a lightness (L*) of between 94 and 100, preferably between 96 and 99. 5 Detailed Description GREEN LEAF TEA We have found that green leaf tea from Camellia sinensis var. assamlca can be used to produce palatable green tea beverages. We have found that if the infusion characteristics of the leaf tea 0 are controlled such that when 2 g of the leaf tea is infused in 200 ml water for 1.5 minutes at 90°C a beverage is produced comprising catechins in an amount of less than 0.1% by weight of the beverage, then the leaf tea is suitable for preparing palatable beverages. The bitterness of the beverages can be 5 further reduced by decreasing the amount of catechins delivered by the leaf tea such that when 2 g of the leaf tea is infused in 200 ml water for 1.5 minutes at 90°C a beverage is produced comprising catechins in an amount of less than 0.09% by weight of the beverage, more preferably less than 0.085%. WO 2008/040627 PCT/EP200 7/059709 - 13 - The leaf tea of the present invention, however, still comprises significant amounts of catechins in order to provide taste and/or health benefits associated with green tea. Thus the infusion characteristics of the leaf tea are controlled such that when 2 g 5 of the leaf tea is infused in 200 ml water for 1.5 minutes at 90°C a beverage is produced comprising catechins in an amount of at least 0.01% by weight of the beverage. In fact, we have found that the amount of catechins delivered by the leaf tea may be as high or even higher than even the most high quality conventional 10 teas from Camellia sinensis var. sinensis without becoming unpalatable. Thus the infusion characteristics of the leaf tea are preferably controlled such that when 2 g of the leaf tea is infused in 200 ml water for 1.5 minutes at 90°C a beverage is produced comprising catechins in an amount of at least 0.04% by 15 weight of the beverage, more preferably at least 0.05% and most preferably at least 0.06%. Despite the relatively low levels of catechins delivered by the green leaf tea, we have found that the levels of certain other 20 actives (such as theanine and caffeine) may be delivered at relatively high levels compared with conventional leaf teas. Thus it is preferred that the green leaf tea delivers theanine such that infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C results in a beverage comprising theanine in an 25 amount of at least 0.004% by weight of the beverage, more preferably from 0.005 to 0.02%, and most preferably from 0.006 to 0.01%. Alternatively or additionally, the infusion characteristics of 30 the leaf tea are such that when 2 g of the leaf tea is infused in 200 ml water for 1.5 minutes at 90°C a beverage is produced comprising caffeine in an amount of at least 0.008% by weight of WO 2008/040627 PCT/EP200 7/059709 - 14 - the beverage, more preferably at least 0.01% and most preferably from 0.012 to 0.03%. The infusion characteristics of the green leaf tea are preferably 5 such that the green leaf tea produces a beverage with high clarity and good colour. In particular it is preferred that the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a haz§ of less than 20 NTU, more preferably less than 15 NTU and most preferably from 1 to 10 10 NTU. Alternatively or additionally, the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a hue (h*) of between 103 and 115, more preferably between 1Q4 and 110; a chroma {C*} of between 6 and 15, more preferably between 8 and 10; and/or a lightness (L*) of between 15 94 and 100, more preferably between 96 and. 99. The infusion characteristics of the leaf tea may be provided in a number of ways including, controlling the particle size of the leaf tea, controlling the catechin content of the leaf tea, 2 0 and/or controlling the degree of damage to the leaf during processing. In general, the larger the particle size of the leaf tea, the less efficient is the catechin delivery. Thus it is preferred 25 that at least 90% by weight of the leaf tea has a particle size above 30 mesh (595 urn), more preferably above 25 mesh (707 \im) and most preferably above 20 mesh (841 ^m). if the particle size is too large, however, the tea may infuse too slowly and/or become difficult to portion and handle. Thus it is preferred that 30 at least 90% by weight of the leaf tea has a particle size below 3 mesh (5.66 mm), more preferably below 4 mesh (4.76 mm) and most preferably below 5 mesh (4.00 mm) . WO 2008/040627 PCT/EP2007/059709 - 15 - Although the infusion characteristics of the leaf tea may be manipulated by controlling the catechin content of the leaf tea, the processes required to achieve this (e.g. partially fermenting 5 or extracting the leaf) would necessarily alter the taste and/or non-flavanol actives provided by the leaf tea. Accordingly it is preferred that the leaf tea retains the high catechin level typical of var. assamica. Thus it is preferred that the catechin content of the green leaf tea is at least 11% by dry weight of 10 the leaf tea, more preferably at least 12% and most preferably from 13 to 20%. The most preferred method of providing the specified infusion characteristics of the leaf tea is by controlling the degree of 15 damage to the leaf during processing, for example by employing the process of the invention. THE PROCESS The process of the invention comprises the steps of: 2 0 (a) providing fresh tea leaves from the plant Camellia sinensis var. assamica; then (b) heat-treating the fresh leaves to arrest enzyme action; then (c) macerating the fresh leaves with a rotorvane and a 2 5 double-cone processor, preferably by passing the fresh leaves through the rotorvane to produce partially macerated leaves and then . passing the partially macerated leaves through the double-cone processor to produce the macerated leaves; then 30 (d) drying the macerated leaves; and then WO 2008/040627 PCT/EP2007/059709 - 16 - (e) optionally sorting the dried macerated leaves according to particle size. Providing fresh leaves 5 In its simplest form, the fresh tea leaves are provided in freshly plucked form, i.e. without any further processing, and have a moisture content of 76 to 80% by weight. The fresh tea leaves preferably comprise leaf and stem material. Most preferably the fresh tea leaves comprise actively growing buds, 0 e.g. in the form of the first two or three leaves together with the unopened bud {so-called Mtwo-and-a-bud" and/or "three-and-a-bud" material). Heat-treatment 5 The heat-treatment of the fresh leaves arrests the enzyme action in the fresh leaves. The heat treatment should be such as to inactivate those endogenous enzymes responsible for fermentation and thus should be sufficient to substantially prevent fermentation during or after maceration (step (c)). Suitable 0 heat-treatments are well-known to those skilled in the art and include steaming and/or pan-firing (see, for example, "Tea: Cultivation to Consumption", K.C. Willson and M.N. Clifford (Eds), 1st Edn, 1992, Chapman & Hall (London), Chapter 13) . Steaming is the preferred mode of heat-treatment as this avoids 5 scorching of the leaf surface which is sometimes encountered in contact-heating such as pan-firing. Scorching of the leaf surface can result in poor infusion characteristics of the made tea, particularly in respect of the colour and clarity of the resulting beverage. WO 2008/040627 PCT/EP200 7/059 709 - 17 - We have found that controlling the moisture content of the fresh leaves prior to heat-treatment allows for convenient handling of the leaf in down-stream processing. In particular, it is preferred that the moisture content of the leaves is controlled 5 to be in the range of 74 to 76% by weight. Suitably, this moisture content is achieved by partially drying the leaves. Maceration Maceration serves two functions. Firstly it damages the leaves 10 such that their contents are more or less accessible to water used to make a beverage. Secondly it changes the shape and size of the leaves. Traditionally, green tea is macerated using batch equipment known 15 as rollers (see, for example, "Tea: Cultivation to Consumption", K.C. Willson and M.N. Clifford (Eds), 1st Edn, 1992, Chapman & Hall (London), Chapter 13) or by rolling by hand. Green teas are also known that are macerated using continuous equipment such as CTC machines. We have found that these known processes have the 20 disadvantage of being unsuitable for continuous manufacture or resulting in too much leaf damage to provide the desirable infusion characteristics of the made tea. We have surprisingly found that maceration using a combination of 25 rotorvane and double-cone processor provides the required amount of leaf damage to produce assamica green leaf tea that allows for the provision of palatable green tea beverages. In particular the leaf damage is such as to provide leaf tea that delivers the taste and actives of green tea, whilst not being too severe so as 30 to provide the leaf tea with so high an efficiency of catechin delivery that beverages produced therefrom are unpalatably WO 2008/040627 PCT/EP200 7/059709 - 18 - bitter. Furthermore, the resulting green leaf tea is found to have a "twisted" appearance similar to that of high quality hand-rolled teas. 5 The preferred arrangement is one wherein the leaves are first passed through the rotorvane and then passed through the double-cone processor. Thus in a preferred embodiment, following heat-treatment, the fresh leaves are passed through the rotorvane to produce partially macerated leaves and then the partially 10 macerated leaves are passed through the double-cone processor to produce the macerated leaves. The maceration is particularly effective if the maceration is performed on fresh leaves having not too high a moisture content. 15 Thus it is preferred that the fresh leaves are partially dried to a moisture content of from 65 to 70% by weight prior to maceration. Maceration is also most effective if the leaves are at a low 20 temperature. Thus it is preferred that the fresh leaves are cooled to a temperature of from 5 to 40°C prior to maceration. Drying Following maceration the leaves are dried. To allow for long-term 25 storage stability, it is preferred that the leaves are dried to a moisture content of less than 30%, more preferably from 1 to 10% by weight of the leaves. Suitable drying processes are known in the art and include tray 30 drying. However, in a most preferred embodiment the drying step WO 2008/040627 PCT7EP2007/059709 - 19 - comprises drying the macerated leaves in a fluid bed dryer as this allows for more uniform heating and prevents the evolution of off-flavours and aromas due to burning. Drying with a fluid bed dryer also avoids scorching of the leaf surface. Scorching 5 can result in poor infusion characteristics of the made tea, particularly in respect of the colour and clarity of the resulting beverage. Sorting 10 The dried macerated leaves are preferably sorted according to particle size. In particular it is preferred that the leaves are sorted to recover those particles with a size larger than 30 mesh (595 (im), more preferably above. 25 mesh (707 urn) and most preferably above 20 mesh (841 ^im) . Sorting may also involve 15 recovering those particles with a particle size below 3 mesh (5.66 mm), more preferably below 4 mesh (4.76 mm) and most preferably below 5 mesh (4.00 mm) . Suitably the step of sorting the leaves comprises sieving the dried macerated leaves. 20 Examples The present invention will be further described with reference to the following examples. EXAMPLE 1 25 Fresh tea leaf (two leaves and a bud) from Camellia sinensis var. assamica was harvested from fields in Kenya. The fresh leaf has a moisture content of 76-80% by weight. The fresh leaf was then air-dried to a leaf moisture content of 75 (±1)%. The leaf was then steamed for 60 seconds at a temperature of 96°C to 30 inactivate any endogenous enzymes and thus prevent fermentation. WO 2008/040627 PCT/EP2007/059709 - 20 - The moisture content of the steamed leaves was then reduced to 67 (±1) % by passing the leaf through two hot air drum driers in series followed by a vibratory bed hot air drier. 5 Leaf at the end of the vibratory bed was cooled to room temperature (~25CC) and then fed to a rotorvane operating at 1500 kg / hour and with the iris opening set at 5.0 cm. Macerated leaf from the rotorvane was then split into two portions and each portion fed through a double-cone processor operating at 750 kg / 0 hour. After the double-cone processing, the macerated leaf was dried in a fluid bed drier to a moisture content of below 3%. Fibres and the secondaries were then removed from the tea leaf and the leaf sieved. The resulting sorted green leaf tea (sample 5 A) had a size range of -5 +20 mesh and a content of catechins of 13.4% by weight. The properties of the leaf tea were compared with a second leaf tea (sample B) prepared in an identical manner except that the 0 macerated leaf from the rotorvane was passed through two CTC machines instead of the double-cone processor. The properties were also compared with those of a high quality commercial green leaf tea (sample C). The results are shown in Table 1. 5 TABLE 1 Sample Variety Catechins (wt %) in Beverage* Properties of Beverage* A Ass arnica 0.072 Pleasant taste, clear liquor B Assami ca 0.123 Bitter taste, hazy liquor C Sinensis 0.055 Pleasant taste, clear liquor * Made by infusing 2 g of sample in 200 ml water for 2 mins at 90°C. WO 2008/040627 PCT/EP2007/059709 - 21 - EXAMPLE 2 A green leaf tea (sample D) was prepared from var. assamica using the method given for sample A detailed in Example 1. The properties of this leaf tea were compared with those of a 5 commercial Japanese green tea (sample E). The results are shown in Tables 2 and 3. TABLE 2 Sample Variety Catechins (wt %) in Leaf Composition of Beverage* (wt%) Catechins Caffeine Theanine D Assamica 14.4 0.078 0.017 0.0088 E Sinensis 11.4 0.077 0.017 0.0032 * Made by infusing 2 g of sample in 200 ml water for 1.5 mins at 90°C. 10 TABLE 3 Sample Variety Colour of Beverage* Haze of Beverage (NTU) L* a* b* C* h* D Assamica 97.29 -2.43 8.84 9.16 105.3 8.94 E Sinensis 90.89 -4.07 18.48 18.92 102.3 52.6 * Made by infusing 2 g of sample in 200 ml water for 1.5 mins at 90CC. WO 2008/040627 PCTYEP2007/059709 - 22 - CLAIMS 1. A green leaf tea from Camellia sinensis var. assamica, wherein infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C produces a beverage comprising catechins 5 in an amount of between 0.01 and 0.1% by weight of the beverage. 2. A green leaf tea according to claim 1 wherein at least 90% by weight of the green leaf tea has a particle size above 30 10 mesh. 3. A green leaf tea according to claim 1 or claim 2 wherein at least 90% by weight of the green leaf tea has a particle size below 3 mesh. 15 4. A green leaf tea according to any one of the preceding claims wherein at least 90% by weight of the green leaf tea has a particle size of -5 +20 mesh. 20 5. A green leaf tea according to any one of the preceding claims wherein the catechin content of the green leaf tea is at least 11% by dry weight. 6. A green leaf tea according to any one of the preceding 25 claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C comprises catechins in an amount of between 0.04 and 0.09% by weight of the beverage, preferably from 0.06 to 0.085%. 30 7. A green leaf tea according to any one of the preceding claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C WO 2008/040627 PCT/EP2007/059709 - 23 - comprises theanine in an amount of at least 0.004% by weight of the beverage, preferably from 0.005 to 0.02%. 8. A green leaf tea according to any one of the preceding 5 claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a haze of less than 20 NTU, preferably from 1 to 15 NTU. 9. A green leaf tea according to any one of the preceding 10 claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a hue (h*) of between 103 and 115, preferably between 104 and 110. 15 10. A green leaf tea according to any one of the preceding claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a chroma (C*) of between 6 and 15, preferably between 8 and 10. 20 11. A green leaf tea according to any one of the preceding claims, wherein the beverage produced by infusion of 2 g of the leaf tea in 200 ml water for 1.5 minutes at 90°C has a lightness (L*) of between 94 and 100, preferably between 96 25 and 99. 12. A green leaf tea according to any one of the preceding claims obtainable by a process comprising the steps of: (a) providing fresh tea leaves from the plant Camellia 30 sinensis var. assamica; then (b) heat-treating the fresh leaves to arrest enzyme action; then WO 2008/040627 PCT/EP2007/059709 - 24 - (c) macerating the fresh leaves with a rotorvane and a double-cone processor, preferably by passing the fresh leaves through the rotorvane to produce partially macerated leaves and then passing the partially macerated leaves through the double-cone processor to produce the macerated leaves; then (d) drying the macerated leaves; and then (e) optionally sorting the dried macerated leaves according to particle size. 13. A process for manufacturing a green leaf tea comprising the steps of: (a) providing fresh tea leaves from the plant Camellia sinensis var. assamica; then (b) heat-treating the fresh leaves to arrest enzyme action; then (c) macerating the fresh leaves with a rotorvane and a double-cone processor, preferably by passing the fresh leaves through the rotorvane to produce partially macerated leaves and then passing the partially macerated leaves through the double-cone processor to produce the macerated leaves; then (d) drying the macerated leaves; and then (e) optionally sorting the dried macerated leaves according to particle size. Dated this 20th day of March 2009

Documents:

554-MUMNP-2009-ANNEXURE TO FORM 3 (30-7-2012).pdf

554-MUMNP-2009-ANNEXURE TO FORM 3(30-7-2012).pdf

554-MUMNP-2009-AUSTRALIAN DOCUMENT(30-7-2012).pdf

554-MUMNP-2009-CLAIMS(AMENDED)-(21-1-2013).pdf

554-MUMNP-2009-CLAIMS(AMENDED)-(30-7-2012).pdf

554-MUMNP-2009-CLAIMS(GRANTED)-(26-2-2013).pdf

554-MUMNP-2009-CLAIMS(MARKED COPY)-(21-1-2013).pdf

554-mumnp-2009-claims.doc

554-mumnp-2009-claims.pdf

554-MUMNP-2009-CORRESPONDENCE(16-6-2010).pdf

554-MUMNP-2009-CORRESPONDENCE(20-3-2009).pdf

554-MUMNP-2009-CORRESPONDENCE(21-1-2013).pdf

554-MUMNP-2009-CORRESPONDENCE(4-6-2009).pdf

554-MUMNP-2009-CORRESPONDENCE(IPO)-(24-9-2009).pdf

554-MUMNP-2009-CORRESPONDENCE(IPO)-(26-2-2013).pdf

554-mumnp-2009-correspondence.pdf

554-mumnp-2009-description(complete).doc

554-mumnp-2009-description(complete).pdf

554-MUMNP-2009-DESCRIPTION(GRANTED)-(26-2-2013).pdf

554-MUMNP-2009-DRAWING(GRANTED)-(26-2-2013).pdf

554-mumnp-2009-drawing.pdf

554-MUMNP-2009-EP DOCUMENT(30-7-2012).pdf

554-mumnp-2009-form 1.pdf

554-MUMNP-2009-FORM 13(8-2-2012).pdf

554-MUMNP-2009-FORM 18(16-6-2010).pdf

554-MUMNP-2009-FORM 2(GRANTED)-(26-2-2013).pdf

554-MUMNP-2009-FORM 2(TITLE PAGE)-(GRANTED)-(26-2-2013).pdf

554-mumnp-2009-form 2(title page).pdf

554-mumnp-2009-form 2.doc

554-mumnp-2009-form 2.pdf

554-MUMNP-2009-FORM 3(13-2-2012).pdf

554-MUMNP-2009-FORM 3(16-8-2011).pdf

554-MUMNP-2009-FORM 3(18-2-2011).pdf

554-MUMNP-2009-FORM 3(20-3-2009).pdf

554-MUMNP-2009-FORM 3(23-1-2013).pdf

554-MUMNP-2009-FORM 3(24-2-2010).pdf

554-MUMNP-2009-FORM 3(3-8-2010).pdf

554-MUMNP-2009-FORM 3(8-8-2012).pdf

554-mumnp-2009-form 3.pdf

554-mumnp-2009-form 5.pdf

554-MUMNP-2009-GENERAL POWER OF ATTORNEY(30-7-2012).pdf

554-MUMNP-2009-JAPANESE DOCUMENT(30-7-2012).pdf

554-MUMNP-2009-KENYAN DOCUMENT(30-7-2012).pdf

554-MUMNP-2009-PCT-IB-345(4-6-2009).pdf

554-mumnp-2009-pct-ipea-409.pdf

554-mumnp-2009-pct-ipea-416.pdf

554-mumnp-2009-pct-isa-210.pdf

554-MUMNP-2009-PETITION UNDER RULE 137(21-1-2013).pdf

554-MUMNP-2009-REPLY TO EXAMINATION REPORT(30-7-2012).pdf

554-MUMNP-2009-REPLY TO HEARING(21-1-2013).pdf

554-MUMNP-2009-RUSSIAN DOCUMENT(30-7-2012).pdf

554-MUMNP-2009-SPECIFICATION(AMENDED)-(21-1-2013).pdf

554-MUMNP-2009-SPECIFICATION(AMENDED)-(30-7-2012).pdf

554-MUMNP-2009-SPECIFICATION(MARKED COPY)-(30-7-2012).pdf

554-MUMNP-2009-US DOCUMENT(30-7-2012).pdf

554-mumnp-2009-wo international publication report a1.pdf

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