WO2016087204A1

WO2016087204A1 - Process for preparing a concentrated tea-based beverage

Info

Publication number: WO2016087204A1
Application number: PCT/EP2015/076958
Authority: WO
Inventors: Hovig YARDIM
Original assignee: Yardim Hovig
Priority date: 2014-12-03
Filing date: 2015-11-18
Publication date: 2016-06-09
Also published as: GB2533549B; GB2533549A; GB201421462D0

Abstract

A process for preparing a concentrated tea-based beverage using an espresso machine, the process comprising: a) placing a measure of ground tea in a portafilter basket; b) placing the portafilter basket in the machine; and c) passing hot water through the ground tea under pressure.

Description

PROCESS FOR PREPARING A CONCENTRATED TEA-BASED BEVERAGE

FIELD OF THE INVENTION

The present invention relates to a process for preparing a concentrated tea-based beverage, the use of the concentrated tea-based beverage in preparing other tea-based beverages and products, and to the concentrated tea-based beverage and other tea-based beverages and products prepared using those processes.

BACKGROUND OF THE INVENTION

In recent years, there has been a rapid increase in the number of cafes, restaurants and other outlets serving a variety of high quality coffee-based beverages. These beverages include caffe lattes, cappuccinos, Americanos, and mochas, all of which are prepared using espresso coffee as the base. Espresso is a concentrated beverage which is extracted by forcing hot water under pressure through finely ground coffee, the pressurized extraction process ensuring that the flavours in a cup (or "shot") of espresso are highly concentrated. The pressurized extraction process used to produce an espresso shot is extremely fast and reliable, such that customers may be served with their beverages in an expedient manner. This is particularly important given that a large proportion of customers order such beverages to "take away". Speed of service is of particular importance where such outlets are located in or near train stations, at motorway service stations, and in other venues where the consumer is en route from one location to another. Consumers obtaining coffee- based beverages at such outlets tend to do so because they are seeking a beverage with a high caffeine content, the beverage is of high quality, there is uniformity in the beverages offered, service is fast, and the consumer values the experience in terms of the aromas, sights and sounds of the coffee-making processes.

By contrast, there is a much more restricted range of tea-based beverages available to the consumer. In terms of obtaining a freshly prepared tea-based beverage at one of the above mentioned outlets, the consumer will generally be offered a simple black or white cup of tea prepared using a conventional tea bag steeped in boiling water, with or without milk added. Thus, the process of preparing the cup of tea is essentially the same as that used in many homes and offices, and the prepared beverage is of no higher quality than one prepared by the consumer in their own home or office. The strength and taste of the cup of tea is also highly dependent on the amount of time that the teabag is steeped in the water, leading to a lack of uniformity in the tea prepared in different outlets and by different personnel. Therefore, such outlets suffer the problem that the appeal of the tea-based beverages on offer is much lower for consumers favouring a tea-based beverage, than the appeal of coffee-based beverages to consumers preferring such beverages. Beverages based on the tea plant {Camellia sinensis) have been popular throughout the world for many hundreds of years. A substantial proportion of the population in the UK, as well as in other countries, prefer the taste of tea-based beverages to coffee-based beverages. Such consumers would welcome the introduction of a new high quality tea-based beverage. Other consumers may be seeking a beverage with a lower caffeine content than traditional coffee-based beverages, but may dislike the taste of decaffeinated coffee. Some consumers would simply appreciate having a good choice of both tea-based beverages and coffee-based beverages of a similarly high quality available to them. Therefore, there is a demand for new tea-based beverages which are of high quality and superior taste, and methods of preparing such beverages which are both rapid and reliable, as well as delivering uniformity in the taste and quality of the beverages produced. There is also a demand for an overall improved customer experience associated with these high quality tea-based beverages and methods for producing them.

Previous attempts have been made to address one or more of these demands. For example, in order to improve the uniformity of taste and speed of producing a tea-based beverage, various instant tea powders have been developed that are free from insoluble leaf tea and therefore dissolve rapidly and completely on contact with hot water. Such instant tea powder products are usually manufactured by a process comprising extracting conventional leaf tea with water and drying the resulting extract. One such product is described in GB 1329612 (Unilever Limited) which relates to an instant tea powder produced using unfired green tea. Another process for producing an instant tea powder product involves steam-stripping tea volatiles from ground leaf tea to form a tea volatiles concentrate, which may then be freeze- dried to a dry powder, as described in US 4,130,669 (The Proctor & Gamble Company).

However, a large proportion of the nutrients, including vitamins, minerals, antioxidants and catechins, are lost during the process of making instant tea powders, and only the flavour and colour of the tea is extracted from the leaves. This makes the known instant tea products substantially inferior in nutritional value to freshly brewed teas. In addition, the extraction and drying process tends to adversely affect the taste of the resultant beverage, and therefore such instant tea powders have not been widely accepted by consumers.

Accordingly, there exists a need for a new type of tea-based beverage which is high quality, has superior taste to existing beverages, can be prepared rapidly, reliably, and uniformly, and provides for an overall improved customer experience. SUMMARY OF THE INVENTION

The present invention seeks to design improved tea-based beverages and methods for producing them which overcomes the problems associated with existing tea- based beverages and production methods as described above. In this respect, the present invention seeks to provide a process for preparing a tea-based beverage in which a desired blend of loose leaf teas is ground to a powder, which is pushed through an espresso-type coffee machine to extract a strong "shot" of tea. This strong "shot" of tea may then be used to create other tea-based beverages, for example, it may be poured into a cup, optionally containing a measure of flavoured syrup, and then steamed milk may be added to create a velvety drink.

In one aspect, the present invention provides a process for preparing a concentrated tea-based beverage using an espresso machine, the process comprising: a) placing a measure of ground tea in a portafilter basket;

b) placing the portafilter basket in the machine; and

c) passing hot water through the ground tea under pressure. In another aspect, the present invention provides a process for preparing a tea-based beverage comprising:

i) placing a measure of flavouring syrup into cup;

ii) adding a measure of the concentrated tea-based beverage prepared according to the process of the invention; and

iii) adding steamed milk.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows a flowchart outlining the various steps of a first embodiment of the process of the present invention.

Figure 2 shows a flowchart outlining the various steps of a second embodiment of the process of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention deals with the problem of providing a new type of tea-based beverage which is of high quality, has superior taste compared to existing beverages, can be prepared rapidly, reliably, and uniformly, and provides for an overall improved customer experience. The inventors identified that a range of tea-based beverages could be created if a satisfactory process could be developed for preparing a concentrated tea-based beverage. This concentrated tea-based beverage could then be mixed with hot water and/or hot milk, and optional other flavourings according to the consumer's preference.

However, in order to produce these beverages in a similar timeframe to coffee-based beverages for on-the-go consumption, the inventors found that it wasn't viable to let the tea steep for sufficient time to produce tea at the high concentration required, since such a method was slow and produced inconsistent results. Neither was it viable to create batches of pre-prepared tea that could be used later in the day as customer orders were received. Such batches of pre-prepared tea had a tendency to "cream" on standing as the tea cooled, causing it to become cloudy and altering the ratio of specific amino acids and polyphenols. The batches of pre-prepared tea were also prone to oxidation and changes in the strength of the tea over time, leading to inconsistent results in terms of flavour, dependent on the length of time that had elapsed since the concentrated tea had been prepared. While oxidation and creaming can be prevented by the addition of an antioxidant, such as citric acid, for example in the form of the juice of a citrus fruit, this can adversely alter the taste.

Accordingly, the inventors have developed a more reliable and rapid method of preparing a concentrated tea-based beverage, involving the use of an espresso machine.

The present invention provides a process for preparing a concentrated tea-based beverage using an espresso machine, the process comprising:

a) placing a measure of ground tea in a portafilter basket;

b) placing the portafilter basket in the machine; and

c) passing hot water through the ground tea under pressure.

The process may optionally comprise the preliminary steps of: (1) mixing tea leaves of more than one variety together to form a blend of tea leaves; and/or (2) grinding the tea leaves or blend of tea leaves to produce ground tea.

The step of grinding the tea leaves or blend of tea leaves preferably takes place within a grinder. A grinder typically has two or more sets of sharp teeth facing one another, commonly referred to as the burrs, which rotate and cut the tea leaves into smaller particles. Adjustment of the distance between the burrs will determine the coarseness or fineness of the resultant ground tea. The tea leaves or blend of tea leaves may be loaded into a hopper, a receptacle that sits on top of the grinder, and the hopper will feed the tea leaves into the grinder. Advantageously, the grinder is attached to or in communication with the espresso machine. Preferably, the step of grinding the tea leaves or blend of tea leaves produces ground tea in which at least about 90wt% of the ground tea has a particle size of less than 2mm.

The present invention further provides for the use of the concentrated tea-based beverage in preparing other tea-based beverages and products. For example, the concentrated tea -based beverage may be mixed with hot water, and/or hot or steamed milk, together with optional flavourings, such as flavoured syrups, to prepare a variety of beverages. The concentrated tea-based beverage may also be formulated and packaged in a suitable container, such as a pouch or carton.

In one preferred embodiment, the present invention provides a process for preparing a tea-based beverage comprising:

i) placing a measure of flavouring syrup into cup;

iii) adding steamed milk. The process may optionally comprise the additional step of d) dusting the beverage with a flavoured powder or sugar, such as cocoa powder, chocolate powder, or cinnamon sugar. The flavoured powder or sugar is preferably dusted over the beverage through a stencil to produce a desired pattern. The following definitions shall apply throughout the specification and the appended claims.

Within the context of the present specification, the term "comprises" is taken to mean "includes" or "contains", i.e. other integers or features may be present, whereas the term "consists of" is taken to mean "consists exclusively of". Within the present specification, the term "about" means plus or minus 20%; more preferably plus or minus 10%; even more preferably plus or minus 5%; most preferably plus or minus 2%. Within the present specification, the term "steep" means the process of soaking tea leaves in water.

Within the present specification, the term "creaming" is used to describe the phenomenon of a brewed tea becoming cloudy as it cools.

Within the present specification, the term "grinder" means a device in which tea leaves or coffee beans are ground to a specific coarseness using rotating burrs.

Within the present specification, the term "portafilter" means a handle which attaches to a group head of an espresso machine, and carries the basket holding the ground tea.

Within the present specification, the term "tamp" means to pack down on the grind in the portafilter basket using a tamper.

The present inventors have identified that it is essential to use ground tea, i.e. leaf tea that has been ground to form fine particles, rather than loose leaf tea or tea from teabags, in the process of the invention. Initial attempts utilising tea bag tea directly in the portafilter basket consistently produced undesirable results, mainly due to blockage of the machine components and/or lack of taste and flavour.

When tea is being processed during its manufacture, the leaves undergo many physical and chemical changes. Following a quick but thorough sifting to sort the leaf into batches of uniform size, rolling twists, compresses, and turns are used to distort the leaf and burst its cellular structure, releasing what is commonly referred to as "juice". This rolling action encourages the internal enzymes and polyphenols to mix, setting in motion the enzymatic oxidation of catechins that eventually promote the oxidation process - turning the withered leaf into tasty black tea.

With tea -bag tea, the dust and fannings from the manufacturing process are used - these are the smaller particles that fall through when sorting by leaf size. As these smaller grades have a higher surface area to weight ratio, the essential oils and flavours evaporate much more quickly than for loose leaf tea, especially as they tend to be packaged with paper, which is not airtight. Therefore, tea from teabags is not suitable for use in the process of the present invention, which requires the volatile oils and gasses imparting a distinctive tea flavour to be present in the final high quality beverage.

Whole loose leaf tea production tends to use the younger leaves at the top of the tea plant, from which the majority of the antioxidants, caffeine and flavour are obtained. Tea bag tea production tends to use the larger, older leaves further down the plant. Therefore, it is desirable to use only loose leaf as there is a higher chance of the catechins and polyphenols being present in the leaf, providing a much higher mineral, antioxidant, flavour and aroma content. However, the inventors established that whole loose leaf tea cannot be used directly in the portafilter basket to obtain a concentrated tea-based beverage, because the flavour is too weak due to the low surface area to weight ratio of the tea leaves.

Accordingly, the inventors have established that it is essential to first grind the loose leaf tea, before using it in the process of the invention.

The size of the particles of the ground tea does affect the efficiency of the process of the invention, as well as the flavour of the beverage produced. If the leaf tea is ground too finely, i.e. there are a large proportion of very small particles, the tea may pass through the holes in the basket, blocking them as it expands, since tea expands when wet. In addition, the use of very finely ground tea may result in sediment being present in the concentrated tea-based beverage. The sediment will tend to settle at the bottom of the cup, and will also continue to steep as the drink is left standing. This will result in a stronger tea taste at the bottom of the cup and a lack of uniformity of the beverage. If the leaf tea is ground too coarsely, there will not be sufficient surface area for the hot water to come into contact with, resulting in the tea-based beverage being too weak, and not of sufficient strength to allow dilution with water, milk, and/or flavourings to create a range of beverages. Therefore the grind needs to be selected at an optimum mid-point for ensuring maximum surface area (and therefore flavour extraction) without blocking the portafilter holes.

Preferably, at least about 90wt% of the ground tea has a particle size of less than 2mm. More preferably, at least about 95wt%, at least about 98wt%, at least about 99wt%, or at least about 99.5wt% of the ground tea has a particle size of less than 2mm. Most preferably, about 100wt% of the ground tea has a particle size of less than 2mm. Preferably, at least about 80wt% of the ground tea has a particle size of less than lmm. More preferably, at least about 90wt%, at least about 95wt%, at least about 98wt%, or at least about 98.5wt% of the ground tea has a particle size of less than lmm. Most preferably, at least about 98.9wt% of the ground tea has a particle size of less than lmm.

Preferably, at least about 60wt% of the ground tea has a particle size of greater than 0.25mm. More preferably, at least about 70wt%, at least about 75wt%, or at least about 78wt% of the ground tea has a particle size of greater than 0.25mm. Most preferably, at least about 80wt% of the ground tea has a particle size of greater than 0.25mm. Accordingly, in one preferred embodiment, at least about 70wt% of the ground tea has a particle size of between about 0.25mm and about lmm. In another preferred embodiment, at least about 80wt% of the ground tea has a particle size of between about 0.25mm and about lmm.

The inventors have found that a grinder setting of between 3 and 8 is required in order to obtain ground tea having a suitable particle size distribution for use in the process of the invention. If the grinder setting is too low, the ground tea will consist of too finely ground particles, which may cause blockage of the machine and/or result in sediment being pushed through into the beverage. If the grinder setting is too high, the ground tea will consist of too coarsely ground particles, and the beverage produced will have a weak flavour.

Individual varieties of loose leaf tea will require slightly different grinder settings in order to obtain ground tea having the optimum particle size distribution for use in the process of the invention. For example, the ideal grinder setting for the Nilgiri Broken Orange Pekoe variety of loose leaf tea is 3.9, the ideal grinder setting for the Kenya Milima variety of loose leaf tea is 4.5, and the ideal grinder setting for the Assam Namdang Broken Pekoe (CTC) variety of loose leaf tea is 7. Therefore, the grinder used to prepare ground tea for use in the process of the invention requires calibration to the specific coarseness required for an individual variety of tea, and any grind pulled thereafter should use the same setting.

If the loose leaf tea is to be used as a blend of different varieties of loose leaf tea, the individual varieties of loose leaf tea may be mixed in the desired ratio to obtain the desired blend of ground tea, and the blended tea is then ground. An optimum grinder setting may be determined for a particularly preferred blend of tea, which produces ground tea having the optimum particle size distribution for use in the process of the invention.

Alternatively, the individual varieties of loose leaf tea may be ground separately, and the varieties of ground tea then mixed in the desired ratio to obtain the desired blend of ground tea. In this embodiment, the different optimum grinder settings for the individual varieties of loose leaf tea may be used.

The quantity (or dose) of ground tea used in the process of the invention is very important. If too much tea is used, this will cause the "shot" to be too strong. In addition, the tea will expand to the top of the basket, touching the group head system in the machine, and potentially allowing tea grinds to be flushed through which may cause damage to the machine. This will also cause an increase in pressure in the system, potentially pushing ground tea particles through and/or blocking the holes in the portafilter basket. If a number of holes in the portaf!lter are blocked, the shot pulled will be inconsistent and unwanted sediment will be apparent in the cup.

If too little tea is used, there won't be enough space to tamp correctly, causing a weak shot, and a possibility of the tea grinds coming loose in the basket as water is introduced, causing it to steep in a traditional manner rather than to be passed through with pressure.

Preferably, the quantity (or dose) of ground tea used in the process of the invention is from about 6.5g to about 10.5g. More preferably, the quantity of ground tea is from about 7.5g to about 9.5g. Most preferably, the quantity of ground tea is from about 8g to about 9g. In a particularly preferred embodiment of the invention, the amount is about 8.5g. Such an amount is ideal for use with a double basket. Preferably, this amount is used for producing a 60ml shot of tea.

As mentioned above, the ground tea used in the process of the invention may be a single variety of loose leaf tea that has been ground. Alternatively, a mixture of two or more varieties may be used, commonly referred to as a blend. Since the concentrated tea-based beverage obtained from the process of the invention is designed to be used as the basis for other beverages, it is important that it has a strong flavour spectrum. Therefore, it is preferred that a blend of at least two, at least three, at least four, or at least five varieties of loose leaf tea is used. After extensive testing and research and development, the inventors created a number of different preferred blends that work, particularly well to impart a full flavour to the concentrated tea -based beverage. Preferably, the blend of ground tea should deliver spicy tones, fruity top notes, full-bodied flavour, and base-line strength, so that the taste carries through to the whole cup following dilution of the concentrated tea-based beverage with hot water, milk, and/or flavouring etc. Accordingly, each variety of tea used should bring their own characteristics to the final blend, allowing the taste to carry through following dilution. For example, when creating a blend that is particularly suitable for use in producing a concentrated tea- based beverage designed to be diluted with steamed milk, creating a so-called Tey Latte™, it is important that the blend creates a tea shot that is sufficiently strong so that the milk flavour does not predominate. Rather, the blend should carry well in the cup and be harmoniously balanced with the milk and flavouring.

It is also important that the varieties of loose leaf tea in the blend are carefully selected to ensure that the distinctive tea taste lasts throughout the cup. Certain blends of tea varieties may work well in terms of the flavour being balanced with the milk, but the tea taste may not carry through to the end of the cup. Thus, the experience of drinking the beverage is comparable to eating chewing gum, the flavour diminishing after a few minutes; this is obviously undesirable. Therefore a blend of teas should be chosen in which the varieties work together to ensure that the last sip is as full of flavour as the first. Preferably, the tea blend comprises one or more varieties of loose leaf tea with a strong and spicy taste. More preferably, the tea blend comprises two or more varieties of loose leaf tea with a strong and spicy taste, the two or more varieties having subtle differences in strength and spiciness. Preferably, the tea blend includes from about 140g to about 260g of strong and spicy tasting tea varieties per kilogram of the tea blend. Where two or more strong and spicy tasting tea varieties are present, the varieties are preferably present in approximately equal amounts. Accordingly, where two varieties are present, they are each present in an amount of from about 70g to about 130g. Particularly preferred varieties of tea having a strong and spicy taste include: Assam tea varieties produced in the Assam region of India, preferably Assam Margherita, Kenyan tea varieties, such as Kenya Milima, and any combination thereof. The Assam Margherita tea variety is stereotypical of a good Assam, having a strong, robust and spicy taste that contributes to the overall strength of the tea, with the Kenya Milima tea variety having a similar but slightly different taste profile with spicy and bold tones which bring an overall strength to the shot. Preferably, the tea blend comprises one or more varieties of loose leaf tea with a bitter and astringent taste. Such a taste profile allows the tea flavour to come through once milk is added, otherwise a very "milky" flavour tends to predominate. Preferably, the tea blend includes from about lOOg to about 300g of bitter and astringent tasting tea varieties per kilogram of the tea blend. Particularly preferred varieties of tea having a bitter and astringent taste include tea varieties produced in Sri Lanka, such as Ceylon tea varieties, preferably Ceylon Gouravilla.

Preferably, the tea blend comprises one or more varieties of loose leaf tea with a full-bodied mid-ranging taste. Such a taste profile harmonises the gap between the spicy tones and the fruity tones of the other tea varieties. Preferably, the tea blend includes from about lOOg to about 300g of full-bodied mid-ranging tea varieties per kilogram of the tea blend. Particularly preferred varieties of tea having a full-bodied mid-ranging taste include Chinese tea varieties, such as Keemun tea varieties, preferably Keemun Dahlia.

Preferably, the tea blend comprises one or more varieties of loose leaf tea with a light, fruity and/or floral taste. Such a taste profile provides the "top notes" that are distinct in a black tea. Preferably, the tea blend includes from about lOOg to about 300g of light, fruity and/or floral tasting tea varieties per kilogram of the tea blend. Particularly preferred varieties of tea having a light, fruity and/or floral taste include tea varieties produced in Sri Lanka, such as Ceylon tea varieties, preferably Ceylon Dote I oy a. Preferably, the tea blend comprises one or more varieties of loose leaf tea with a robust, full-ranging taste. Such a larger ranged taste profile allows the tea varieties that are just spicy or just fruity/floral to work alongside other tea varieties in the tea blend, by filling the gaps with its wider flavour profile. Preferably, the tea blend includes from about lOOg to about 300g of robust, full-ranging tasting tea varieties per kilogram of the tea blend. Particularly preferred varieties of tea having a robust, full-ranging taste include other Indian or Chinese grown tea varieties, preferably Nilgiri BOP.

Once ground tea is placed in the portafilter basket, it should be tamped. Tamping is the process of pressing down on the ground tea in the basket to ensure it is packed in well, slowing down the water flow rate through the tea, as compared to the flow rate through ground tea that has not been tamped. This ensures maximum flavour extraction as the slower water flow rate ensures a higher yield of flavour due to a longer contact time with the ground leaves. When placing the ground tea in the basket, the tea is preferably levelled before tamping to ensure that the tea is evenly tamped. If the ground tea is not levelled prior to tamping and is uneven, then a greater proportion of the tea may be compacted into one side of the basket, encouraging water through the looser part.

Channelling may occur when the tamp is not firm enough. Channelling is the term given when water passes through the grind unevenly, and instead of filtering through the ground tea, maximising contact with each grain to extract the maximum potential flavour, it finds a larger gap between loose grounds, encouraging the rest of the water to pass through this channel, and reducing the amount of tea it comes into contact with, thereby limiting flavour extraction.

Although not essential, the tamp pressure preferably should be between about 5 and about 15 pounds per square inch (psi) (from about 0.34 bar to about 1.03 bar). More preferably, the tamp pressure is from about 7 psi to about 12 psi, or from about 8 psi to about 11 psi, with the optimal tamp pressure being around 10 psi. If the tamp pressure is less than about 5 psi, then the ground leaves may float around when the hot water is introduced, resulting in an uneven tea shot. If the tamp pressure is more than about 15 psi, the holes in the portafilter basket may become blocked due to the high pressure pushing the ground tea into the holes, that tea expanding as it becomes wet, and causing the blockage.

The portafilter basket used for preparing a concentrated tea-based beverage according to the process of the invention may be of any suitable size and shape. Generally, a portafilter basket has a circular cross-section with a diameter of from about 40 mm to about 80 mm. The most common sizes of portafilter baskets have a diameter of 40mm, 53mm, or 58mm, with the 53mm and 58mm diameter portafilter baskets being particularly prevalent. The use of a portafilter baskets having a relatively smaller diameter results in there being a relatively taller column of ground tea than for a larger diameter portafilter basket, when using a predetermined amount of tea. This taller column allows the water to come into contact with more tea on its way through the tamped ground tea. Therefore a portafilter basket having a 53mm diameter is preferred.

As the bulk of the shot is made of water, it is important to ensure that the best quality water is used. The water used in the process of the invention must be potable water. Preferably, the water is sou reed from mains water, and not from bottled mineral water which has too high a mineral content.

In one preferred embodiment, a Calcium Treatment Unit (CTU) is used to regulate the mineral content of mains water which is pumped through it, in order to produce consistent results. The CTU does not remove all of the minerals since this would produce 'distilled' water, which when used as a base for drinks produces very 'flat' results, not allowing the flavour to carry through. Another advantage in using a CTU unit is that it helps to preserve the life of the espresso machines used, by preventing a build-up of limescale which will damage the boiler in the machine over time. It is fairly common practice to have a CTU unit installed on or in conjunction with an espresso machine. In another embodiment, mains water may be filtered, for example using a jug-type filter, prior to use of the water in the process of the invention. The volume of water used in the process of the invention is typically in the region of about 50ml to about 70 ml, more preferably about 55ml to about 65ml, most preferably about 60ml. This volume of water should produce about 60ml of the concentrated tea -based beverage, which corresponds to the volume of a typical as a double espresso coffee. This volume of water and corresponding volume of the concentrated tea-based beverage produced should be sufficient for preparing further diluted tea -based beverages, such as a so-called Tey Latte™, in a standard 340ml cup size (commonly referred to as a 12oz cup).

Flavour and nutrient extraction varies greatly depending on the temperature of the water used. If the temperature of the water is too high, the ground tea leaves can be "burnt", causing an unpleasant bitter taste. If the temperature of the water is too low, certain nutrients will not be extracted adequately, causing a reduction in taste. Therefore, it is essential that the temperature of the water used is within certain parameters. In particular, the process requires that the water temperature is within the range of from about 80°C to about 105°C. In this context, the water temperature refers to the temperature of the water as it leaves the group head and enters the portafilter. The water temperature may be higher than this in the boiler, since the temperature may reduce as the water passes through the pipework taking it to the group head and ultimately into the portafilter.

Preferably, the water temperature used in the process of the invention is at least about 85°C, at least about 90°C, at least about 91°C, at least about 92°C, or at least about 93°C. Preferably, the water temperature used in the process of the invention is no higher than about 100°C, about 99°C, about 98°C, or about 97°C. In one preferred embodiment of the invention, the water temperature is within the range of from about 90°C to about 100°C. In another preferred embodiment of the invention, the water temperature is within the range of from about 93°C to about 97°C. As discussed above, the traditional method of producing tea, namely steeping the tea leaves in hot water, is too slow and would take too long to produce a concentrated tea-based beverage of the concentration required to enable its use in preparing a variety of beverages by dilution with hot water, milk etc. This traditional method does not produce a tea concentrate that is strong enough to carry through to a whole cup once steamed milk and/or other diluents are added.

A high pressure system (similar to that used for coffee) allows the extraction to take place in a fraction of the time. A portafilter basket is used because the placement of the holes in the basket allows an even flow of water from the group head, through the ground tea, and into the outlet.

The pressure used in the high pressure system is preferably between about 4 bar and about 25 bar. More preferably, the pressure used is from about 4 bar to about 14 bar, yet more preferably about 8 bar to about 10 bar. Most preferably, the pressure applied through the portafilter basket is around 9 bar.

While higher pressure could be used to speed up the process of the invention, this is not the best option, since if the pressure is raised, the ground tea is pushed through the holes in the portafilter, blocking it as it expands. Making the grind coarser to compensate for this doesn't work as there isn't enough surface area for maximum flavour extraction into the final shot. Therefore, the maximum pressure used is preferably about 14 bar, about 12 bar, about 11 bar, about 10 bar, about 9.5 bar, about 9.3 bar, about 9.2 bar, or about 9.1 bar.

The minimum pressure used is preferably about 4 bar, about 6 bar, about 7 bar, about 8 bar, about 8.5 bar, about 8.7 bar, about 8.8 bar, or about 8.9 bar.

The present invention also provides for the use of the concentrated tea-based beverage in the preparation of other tea-based beverages. For example, the concentrated tea-based beverage produced by the process of the invention may be mixed with one or more of hot water, cold milk, hot milk, flavourings etc. In particular, the present invention provides a process for preparing a tea-based beverage comprising:

i) placing a measure of flavouring syrup into cup;

iii) adding steamed milk.

Preferably, the measure of flavouring syrup is from about 5ml to about 15ml for a 340ml cup (commonly referred to as a 12oz cup) of the resultant beverage. More preferably, the measure of flavouring syrup is about 10ml per 340ml cup.

Preferably, the measure of the concentrated tea-based beverage is from about 55ml to about 70ml for a 340ml cup (commonly referred to as a 12oz cup) of the resultant beverage. More preferably, the measure of the concentrated tea -based beverage is from about 58ml to about 65ml, most preferably about 60ml for a 340ml cup.

Steamed milk is then added to bring the contents of the cup up to about 340ml. Accordingly, the amount of steamed milk used is from about 255ml to about 280ml for a 340ml cup (commonly referred to as a 12oz cup) of the resultant beverage. More preferably, the amount of steamed milk used is from about 265ml to about 275ml for a 340ml cup. Most preferably, the amount of steamed mi!k used is about 270ml for a 340ml cup. Any type of milk may be used for mixing with the concentrated tea-based beverage. For example, full -fat, semi-skimmed, or skimmed cows' milk, may be used. Alternatively, goats' milk, soya milk, almond milk, rice milk, or other alternatives may be used. In a preferred embodiment, the milk used is full-fat cows' milk. The fats and sugars in full-fat milk help to carry the flavour of the syrup and contribute to the overall texture of the final product. Steaming the milk correctly is fundamental in creating a so-called Tey Latte™. To ensure that the milk is steamed evenly, a vortex is preferably created in the jug, and ideally air should be introduced early on in the steaming process, lowering the jug as the milk is "stretched" in volume to ensure that the tip of the steam wand is introducing air into the milk through to about halfway through the process. The tip is then inserted below the surface to evenly distribute the air and produce an even micro-foam. This gives the final product the overall velvety texture and prevents a milky taste from predominating. Milk that has been steamed with less air creates a milky product. Highly aerated milk creates too much foam, which doesn't mix well with the concentrated tea-based beverage and flavouring, creating too strong a flavour at the bottom of the cup due to the poor mixing. The pour is important in ensuring a good consistency and even distribution of flavour within the beverage. Preferably, the flavour shot is first pumped into the cup, followed by pouring in the shot of tea. Alternatively, the shot of tea can first be poured into the cup, followed by adding the flavour shot. When the milk is added, the initial pour needs to be fast to agitate the bottom of the cup, mixing in well with the flavour shot and tea shot. This is best achieved if the milk is poured into one corner of the bottom of the glass with the glass slightly tilted, creating a swirl effect, pulling the contents of the cup upwards. Once about halfway, the pour rate needs to be reduced and the glass straightened to ensure that bubbles aren't introduced to the mix, showing off the velvety consistency of the milk. As the pour reaches completion, the more aerated part of the milk will sit on the surface of the cup, creating a small layer of foam that powder can be sprinkled on (cocoa, chocolate, cinnamon, brown sugar etc). The present invention also relates to the concentrated tea-based beverage produced according to the processes of the invention, as well as to other tea-based beverages produced according to the processes of the invention. The concentrated tea -based beverage can conveniently be packaged in a pouch or other container for direct retail to consumers. Such a pouch or container may be conveniently used in the home by the consumer in order to prepare a tea-based beverage. Typically the contents of the pouch or container is emptied into a cup or mug, and a suitable diluent, such as hot or steamed milk, is added.

Accordingly, in one embodiment, the present invention provides a container comprising the concentrated tea-based beverage, and optional additional ingredients selected from the group consisting of flavoured syrups, preservatives, stabilisers, antioxidants, and combinations thereof. In one preferred embodiment, the present invention provides a container comprising the concentrated tea-based beverage, one or more flavoured syrups, and citric acid. The present invention also relates to the provision of ground tea in a convenient capsule, commonly referred to as a pod, for use in producing a concentrated tea- based beverage. Accordingly, the present invention provides a capsule containing ground tea. The capsule may conveniently be used for preparing a concentrated tea-based beverage.

The capsule or pod may be formed from any suitable material, such as metal or plastics material. The capsule or pod is preferably an airtight capsule or pod, so that the freshness of the contents is retained. In one preferred embodiment, at least about 70wt% of the ground tea within the capsule has a particle size of between about 0.25mm and about lmm. In another preferred embodiment, at least about 80wt% of the ground tea within the capsule has a particle size of between about 0.25mm and about lmm. In one embodiment, the ground tea comprises a blend of one or more varieties of tea which have been blended together and then ground. In another embodiment, the ground tea comprises a blend of one or more varieties of tea which have been ground individually and then blended together. Since such capsules may be produced on a commercial scale, it is possible to grind a batch of each individual tea variety using the optimum grinder setting for that particular variety of tea and subsequently blend the ground tea varieties together. This has the advantage that the particle size of the ground tea blend will be more consistent and lead to an improved flavour.

Such capsules are suitable for retail to consumers and may be used to prepare a concentrated tea-based beverage. Accordingly, the present invention also provides the use of a capsule as described above for producing a concentrated tea -based beverage.

Accordingly, the present invention also provides a process for preparing a concentrated tea-based beverage using an espresso machine designed to accommodate capsules, the process comprising:

a) loading a capsule of ground tea into the machine; and

b) passing hot water through the capsule of ground tea under pressure.

This process is particularly advantageous in that it removes the need for a tamping step thus making the process more efficient, it removes any user-generated errors and/or variability in the quantity of tea used, it reduces the possibility of blockages, and it results in simpler cleaning and disposal following use of the capsule.

Preferred features of the process using loose ground tea, in terms of the water temperature, pressure etc, are equally applicable to the process described above utilising capsules of ground tea. EXAMPLES

Example 1

Tea was obtained from tea bags by opening the bags and utilising the tea directly. An 8.5g measure of the obtained tea was placed in a portafilter basket, the tea was tamped down, the portafilter basket was placed in an espresso machine, and hot water (around 90°C - 100°C) was passed through the ground tea at a pressure of around 9bar.

Results

Brand A - The tea produced strong flavours in the shot. However, because the tea is low quality tea, it has a lot of dust (i.e. very fine particle sizes), which caused a lot of problems by blocking the machine after every use. In addition, a large quantity of tea particles were pushed through the portafilter holes, and therefore filtered through into the resultant tea shot.

Brand B - The tea produced weaker flavours in the shot compared to Brand A. No further testing was carried out due to the poor flavour.

Brand C - The tea produced a similar strength of flavour in the shot as compared to Brand A, but the tea shot was lacking in "body" as compared to Brand A. No further testing was carried out due to the flavour being inferior to Brand A.

Example 2

A loose leaf black tea blend including ginger and wild calendula was tested. The loose leaf tea was ground in a small blender for between 2 and 10 seconds. An 8.5g measure of the obtained tea was placed in a portafilter basket, the tea was tamped down, the portafilter basket was placed in an espresso machine, and hot water (around 90°C - 100°C) was passed through the ground tea at a pressure of around 9bar.

It was found that the particle sizes of the ground tea were too varied and not consistent; this resulted in some blockage of the portafilter basket holes and sediment in the cup from the fine particles, as well as insufficient strength due to poor extraction efficiency from the coarser particle sizes. In addition, the additional ginger and calendula flavours did not work well once the tea shot was mixed with flavoured syrups.

Other blends of loose leaf tea, including Golden Blend, Spiced Black, and Orient Blend were tested but similar results were obtained.

Example 3

Individual varieties of loose leaf black tea were ground at a number of different grinder settings. An 8.5g measure of the single variety ground tea was placed in a portafilter basket, the tea was tamped down, the portafilter basket was placed in an espresso machine, and hot water (around 90°C - 100°C) was passed through the ground tea at a pressure of around 9bar. This process was repeated for the ground tea obtained using a variety of grinder settings.

The results are summarised below, using the following definitions: Clean = no blockage; Block = portafilter blocked; Dirty = sediment in cup; Strong/Medium/Weak = strength of tea.

Variety A - Ideal grinder setting 7

No block at 7.2 but too weak.

Clean and strong at 7

Blocked at strong 6.8

Blocked and strong at 6.5

Blocked and weak at 4.8

Variety B - Ideal grinder setting 5

Clean but no strength at 6

Blocks everything up to 4.8

Full strength but block and sediment pushed through at 4 Variety C - Ideal grinder setting 4.5

Clean and weak at 5

Clean and medium/strong 4.5

Block and dirty at 4.2

Block and dirty at 4

Variety D - Ideal grinder setting 3.5

No strength or blockage at 4.8

Clean and medium at 3.6

Clean and medium/strong at 3.5

Block and strong at 3

Block and strong at 3.3

Block and strong at 3.4 Variety E - Ideal grinder setting 3.9

No strength or blockage at 4.8

Clean and medium at 4

Clean and medium/strong at 3.9

Block and strong at 3.5

Block and strong at 3.7

Block and strong at 3.8

Variety F - Ideal grinder setting 5

Clean but no strength at 6

Blocks everything up to 4.8

Full strength but block and sediment pushed through at 4

Variety G - Ideal grinder setting 4.7

Clean and weak at 5.3

Clean and medium at 4.8

Block and dirty at 4

Block and dirty at 4.2 Block and clean at 4.5

Variety H - Ideal grinder setting 4.1

Clean and weak at 6

Clean and medium/strong at 4.5

Block and dirty at 3.5

Clean and strong at 4.2

Dirty at 4.0 From the results above, the ideal grinder settings for each variety of tea could be obtained. It is envisaged that a similar process could be used to calibrate grinder settings when using a different type of grinder and/or when testing additional varieties of loose leaf tea to determine the optimum setting. Example 4

A batch of a ground tea blend (lkg) was created by mixing loose leaf tea in the approximate amounts shown below:

Variety H -lOOg

Variety C -lOOg

Variety F -200g

Variety D -200g

Variety G -200g

Variety E -200g

Samples of the blended loose leaf tea were ground at a number of different grinder settings to determine the optimum grinder setting for the blend in a similar process to that described in Example 3. The batch of blended loose leaf tea was then ground at the optimum grinder setting for the blend to produce a batch of the ground tea blend. The ground tea blend (lOOg sample) was analysed in a particle size analyser machine (Octagon 200) using 4 X 200mm diameter sieves to determine the particle size distribution of the ground tea leaves. The four sieves are placed on top of one another, with the largest grid at the top, and the smallest grid at the bottom. The machine was run for a specified period of time, during which the vibration of the machine caused particles to fall through the mesh of the sieves as appropriate for specific particle sizes. Following the completion of the run, the individual sieves were weighed to determine the amount of particles retained, and thus the particle size distribution.

In the first experiment, the machine was run continuously for 10 minutes, and the results of this are given below.

- AMPLITUDE 5, TIME 10 MINS CONTINUOUS

In summary, it was found that 100% of the ground tea leaf particles were smaller than 2mm diameter, and 99% of the ground tea leaf particles are smaller than lmm diameter. The largest percentage of particles (46.0%) were trapped by the 500 micron (0.5mm) sieve, and a further 37.6% of particles were trapped by the 250 micron (0.25mm) sieve. Therefore, the percentage of ground tea leaf particles having a particle size diameter in the range of between lmm and 0.25mm was 83.6%, with the larger percentage of 46.0% having a particle size diameter between lmm and 0.5mm. Example 5

The ground tea blend (lOOg sample) as obtained in Example 4 was analysed in a particle size analyser machine (Octagon 200) using 4 X 200mm diameter sieves to verify the particle size distribution of the ground tea leaves. In this second experiment, the machine was run intermittently for 10 minutes, and the results are given below. As can be seen, the results are fairly similar to those determined in Example 4, indicating that the particles behave in a similar manner in both tests and verifying the accuracy of the measurements.

AMPLITUDE 5, TIME 10 MINS WITH INTERMITTENT

In summary, it was found that 100% of the ground tea leaf particles were smaller than 2mm diameter, and 98.96% of the ground tea leaf particles were smaller than lmm diameter. The largest percentage of particles (46.27%) were trapped by the 500 micron (0.5mm) sieve, and a further 39.96% of particles were trapped by the 250 micron (0.25mm) sieve. Therefore, the percentage of ground tea leaf particles having a particle size diameter in the range of between lmm and 0.25mm was 86.23%, with the larger percentage of 46.27% having a particle size diameter between lmm and 0.5mm.

Embodiments have been described herein in a concise way. It should be appreciated that features of these embodiments may be variously separated or combined within the invention.

Claims

1. A process for preparing a concentrated tea-based beverage using an espresso machine, the process comprising:

a) placing a measure of ground tea in a portafilter basket;

b) placing the portafilter basket in the machine; and

c) passing hot water through the ground tea under pressure.

2. The process according to claim 1, wherein at least about 90wt%, at least about 95wt%, at least about 98wt%, at least about 99wt%, at least about 99.5wt%, or substantially 100wt%, of the ground tea has a particle size of less than 2mm.

3. The process according to claim 1 or claim 2, wherein, at least about 80wt%, at least about 90wt%, at least about 95wt%, at least about 98wt%, or at least about 98.5wt%, or at least about 98.9wt%, of the ground tea has a particle size of less than lmm.

4. The process according to any of claims 1 to 3, wherein at least about 60wt%, at least about 70wt%, at least about 75wt%, at least about 78wt%, or at least about 80wt%, of the ground tea has a particle size of greater than 0.25mm.

5. The process according to any of claims 1 to 4, wherein at least about 70wt%, or at least about 80wt%, of the ground tea has a particle size of between about 0.25mm and about lmm.

6. The process according to any of claims 1 to 5, wherein the ground tea comprises a blend of different varieties of loose leaf tea which have been mixed together in a desired ratio and ground.

7. The process according to any of claims 1 to 6, wherein the measure of ground tea used is from about 6.5g to about 10.5g, from about 7.5g to about 9.5g, from about 8g to about 9g, or about 8.5g.

8. The process according to any of claims 1 to 7, wherein following the placing of a measure of ground tea in a portafilter basket in step a) of the process, the ground tea is tamped at a tamp pressure of from about 5 psi to about 15 psi.

9. The process according to any of claims 1 to 8, wherein the volume of hot water used in step c) of the process is from about 50ml to about 70 ml, from about 55ml to about 65ml, or about 60ml.

10. The process according to any of claims 1 to 9, wherein the temperature of the hot water used in step c) of the process is at least about 85°C, at least about 90°C, at least about 91°C, at least about 92°C, or at least about 93°C.

11. The process according to any of claims 1 to 10, wherein the temperature of the hot water used in step c) of the process is no higher than about 100°C, about

99°C, about 98°C, or about 97°C.

12. The process according to any of claims 1 to 11, wherein the pressure used in step c) of the process is at least about 4 bar, at least about 6 bar, at least about 8 bar, at least about 8.5 bar, at least about 8.7 bar, at least about 8.8 bar, or at least about 8.9 bar.

13. The process according to any of claims 1 to 11, wherein the pressure used in step c) of the process is no higher than about 25 bar, about 22 bar, about 19 bar, about 14 bar, about 12 bar, about 11 bar, about 10 bar, about 9.5 bar, about 9.3 bar, about 9.2 bar, or about 9.1 bar.

14. A concentrated tea-based beverage obtained using the process according to any of claims 1 to 13.

15. A pouch or container comprising the concentrated tea-based beverage according to claim 14, and optionally additional ingredients selected from the group consisting of flavoured syrups, preservatives, stabilisers, antioxidants, and combinations thereof.

16. A pouch or container comprising the concentrated tea-based beverage according to claim 14, one or more flavoured syrups, and citric acid.

17. A capsule containing ground tea, wherein at least about 70wt% of the ground tea within the capsule has a particle size of between about 0.25mm and about lmm.

18. A capsule according to claim 17, wherein the ground tea comprises a blend of one or more varieties of tea which have been ground individually and then blended together.

19. A capsule according to claim 17 or claim 18, wherein the capsule is formed from a metal or plastics material.

20. Use of a capsule according to any of claims 17 to 19 for producing a concentrated tea-based beverage.

21. A process for preparing a concentrated tea-based beverage using an espresso machine designed to accommodate capsules, the process comprising:

a) loading a capsule according to any of claims 17 to 19 into the machine; and b) passing hot water through the capsule of ground tea under pressure.

22. The process according to claim 21, wherein the temperature of the hot water used in step b) of the process is at least about 85°C, at least about 90°C, at least about 91°C, at least about 92°C, or at least about 93°C, and/or wherein the temperature of the hot water used in step b) of the process is no higher than about 100°C, about 99°C, about 98°C, or about 97°C.

23. The process according to claim 21 or claim 22, wherein the pressure used in step b) of the process is at least about 4 bar, at least about 6 bar, at least about 8 bar, at least about 8.5 bar, at least about 8.7 bar, at least about 8.8 bar, or at least about 8.9 bar, and/or wherein the pressure used in step b) of the process is no higher than about 14 bar, about 12 bar, about 11 bar, about 10 bar, about 9.5 bar, about 9.3 bar, about 9.2 bar, or about 9.1 bar.

24. A process for preparing a tea-based beverage comprising:

i) placing a measure of flavouring syrup into cup;

ii) adding a measure of the concentrated tea-based beverage prepared according to the process according to any of claims 1 to 13 or claims 21 to 23; and

iii) adding steamed milk.

25. The process according to claim 24, wherein the measure of flavouring syrup is from about 5ml to about 15ml, the measure of the concentrated tea-based beverage is from about 55ml to about 70ml, and steamed milk is added to bring the volume of of the tea-based beverage up to about 340ml cup.

26. The process according to claim 24 or claim 25, wherein the steamed milk used in step iii) of the process is selected from the group consisting of full -fat cows' milk, semi-skimmed cows' milk, skimmed cows' milk, goats' milk, soya milk, almond milk, rice milk, and combinations thereof.