METHOD FOR PREPARING AN ICED TEA OR COFFEE BEVERAGE

Abstract

The present invention provides a method for preparing an ice-containing tea or coffee beverage, the method comprising: (i) providing a beverage liquor containing soluble tea or coffee solids, and a freezing-point suppressant; (ii) aerating the beverage liquor by the addition of a gas; (iii) flowing the aerated beverage liquor through a refrigeration system to cool the aerated beverage liquor and to thereby form a plurality of ice crystals within the aerated beverage liquor; and (iv) dispensing the cooled aerated beverage liquor as an ice-containing tea or coffee beverage.

Claims

1. A method for preparing an ice-containing tea or coffee beverage, the method comprising: (i) providing a beverage liquor containing soluble tea or coffee solids, and a freezing-point suppressant; (ii) aerating the beverage liquor by the addition of a gas; (iii) flowing the aerated beverage liquor through a refrigeration system to cool the aerated beverage liquor and to thereby form a plurality of ice crystals within the aerated beverage liquor; and (iv) dispensing the cooled aerated beverage liquor as an ice-containing tea or coffee beverage.

2. The method of claim 1, wherein the beverage liquor comprises 0.5 to 6 wt % soluble tea or coffee solids.

3. The method of claim 1, wherein the freezing point suppressant is present in an amount sufficient to suppress the melting point of the liquor by from 0.2 to 3 C. compared to water, preferably from 0.2 to 1 C. compared to water.

4. The method of claim 1, wherein the freezing point suppressant is selected from the group consisting of a sweetener, a sugar, a polyol, and mixtures of two or more thereof.

5. The method of claim 1, wherein the beverage liquor comprises 3.2 to 25 wt % sugar, preferably 5 to 8 wt % sugar.

6. The method of claim 1, wherein the beverage liquor comprises fats in an amount of less than 20 wt %, preferably less than 10 wt % and, preferably is free of dairy solids.

7. The method of claim 1, wherein the beverage liquor is free from gums, thickeners and stabilisers.

8. The method of claim 1, wherein the step of aerating the beverage liquor introduces gas in an amount sufficient to achieve an overrun of from 10 to 150%, preferably 25 to 100%.

9. The method of claim 1, wherein the added gas in the step of aerating the beverage liquor is air or nitrogen.

10. The method of claim 1, wherein the step of aerating the beverage liquor involves inline addition of the gas into the flow of the beverage liquor.

11. The method of claim 10, wherein the inline addition of gas is through a plurality of gas inlet orifices.

12. The method of claim 10, wherein the step of aerating the beverage liquor further comprises passing the flow of the beverage liquor with the added gas through a static mixer or one or more constricting orifices.

13. The method of claim 1 wherein the refrigeration system is a refrigeration circuit comprising a recirculation flow-path.

14. The method of claim 1 wherein the refrigeration system comprises a plastic duct within which the aerated beverage liquor is cooled.

15. The method of claim 1 wherein the refrigeration system comprises a heat exchanger having a first surface in contact with the flow of aerated beverage liquor and a second surface in contact with a chilled coolant liquid.

16. The method of claim 15, wherein the chilled coolant liquid comprises propylene glycol and is at a temperature of from 5 C. to 10 C.

17. An aerated ice-containing beverage obtainable by the method of claim 1.

18. An aerated ice-containing beverage comprising: (a) 0.5 to 6 wt % soluble tea or coffee solids, (b) one or more freezing point suppressants, preferably sucrose, (c) less than 10 wt % fats, and (d) the balance substantially ice and water, wherein the one or more freezing point suppressants are present in an amount sufficient to suppress the melting point of the water by from 0.2 to 3 C.; the beverage having an overrun of from 10 to 150%, the ice having an average ice-crystal size of from 0.1 to 1 mm, and wherein for at least 10 minutes after production the beverage does not form a distinct non-foamed or non-ice-containing layer.

19. The aerated ice-containing beverage according to claim 18, which is free from gums, thickeners and stabilisers.

20. Apparatus for preparing an ice-containing tea or coffee beverage, the apparatus comprising: (i) a source of beverage liquor; (ii) a refrigeration system comprising a refrigeration circuit in fluid connection with the source of beverage liquor via a supply duct; (iii) a pump arranged to circulate the beverage within the refrigeration circuit; (iv) a beverage dispensing outlet for dispensing an ice-containing tea or coffee beverage from the refrigeration circuit into a receptacle; and (v) a source of pressurised gas arranged to deliver pressurised gas into the supply duct for aerating the beverage liquor.

Description

[0079] The invention will now be described in relation to the following non-limiting figures, in which:

[0080] FIG. 1A shows the ice crystals produced according to the method described herein.

[0081] FIG. 1B shows the ice crystals produced according to a prior art scraped surface method.

[0082] FIG. 2 shows a schematic of the apparatus usable according to the method described herein.

[0083] As shown in FIG. 2 there is an apparatus 1 for preparing an ice-containing tea or coffee beverage. The apparatus 1 comprises a reservoir 5 for holding a beverage liquor. The reservoir 5 may have means for stirring or agitating the liquor.

[0084] The reservoir 5 is connected via a supply duct 10 to a refrigeration circuit 15. The refrigerant circuit 15 comprises a plastic duct 16 within which the liquor flows, which has a recycle loop to permit the liquor to recirculate within the circuit 15. The refrigeration circuit 15 comprises a heat exchanger 20 for cooling the liquor using pre-chilled refrigerant, such as propylene glycol at a temperature of from 5 C. to 10 C., which is flowed within a separate duct 25.

[0085] The refrigeration circuit 15 is also in fluid communication with a dispensing outlet 30 for dispensing an ice-containing tea or coffee beverage from the refrigeration circuit 15 into a receptacle 35.

[0086] A source of pressurised gas 40, such as a gas cylinder, is provided to supply pressurised gas into the supply duct 10 for aerating the sweetened beverage liquor. The gas may be supplied through a nozzle having a plurality of inlets to encourage the formation of fine bubbles, but a single nozzle entry will suffice. The gas mixing may also or alternatively involve a static mixer or one or more constricting orifices 41.

[0087] A pump 45 is also provided to circulate the sweetened beverage within the refrigeration circuit 15. This is provided within the refrigeration circuit 15, but a further pump may be provided in the supply duct 10.

[0088] In use, the apparatus 1 shown in FIG. 2 allows the preparation of an ice-containing tea or coffee beverage. Beverage liquor containing soluble tea or coffee solids and a freezing point suppressant is pumped or driven with pressurised gas from the reservoir 5, through the supply duct 10 to the refrigeration circuit 15. Gas is dosed into the supply duct 10 from the gas source 40 via mixing means 41, such as a through-flow aperture or orifice.

[0089] The liquor circulates, driven by the pump 45, within the refrigeration circuit 15 and through the heat exchanger 20, where it is cooled so that ice crystals form slowly. Due to the plastic surface of the duct 16, the ice crystals tend to be small and rounded.

[0090] An ice-containing tea or coffee beverage is dispensed on demand from the circuit 15 via the outlet 30 into the beverage receptacle 35. The gas is added to provide an overrun of from 25 to 100%. The added gas is preferably air or nitrogen.

[0091] The appearance of the beverage which is produced will depend on the ice-fraction and the overrun of the beverage. A beverage with a high overrun, such as 100% and a low ice-fraction, such as 10 to 20%, will resemble a homogeneous light brown foam and will retain this form and stability for upward of 10 minutes. In practice the ice is well insulated and melts slowly. Eventually an underlying coffee or tea layer may form, but this will typically take at least 30 minutes. No separate water layer will form, as would be seen in a beverage made from coarse ice-crystals. In a beverage with coarser ice-crystals, these typically migrate to the top as they are least dense and then melt without the beverage solids being present.

[0092] A beverage with a lower overrun, such as 25% and with a higher ice fraction, such as 30%, may form an initial thicker foam layer on a darker beverage layer. However, the whole structure will have an even distribution of ice and will not form a separate water layer. Instead it may resemble, albeit with less separation, the classic beverage Guinness appearance of a dark liquor with a foamed head and demonstrates a storm-cloud settling effect. The foam persists in part because it is stabilised by the fine ice-crystals distributed therein.

[0093] The invention will now be described in relation to the following non-limiting examples.

[0094] An initial beverage liquor was prepared including water, together with re-dissolved freeze dried coffee and granulated sugar (sucrose). The soluble coffee solids were 1.5 wt %. The sugar was in an amount of 8 wt %, which is enough to depress the melting point of water by approximately 0.8 C. No fat-containing ingredients were present.

[0095] Food grade nitrogen was added from a compressed gas cylinder at about 4 bar through a single injection needle into the liquid inlet flow at approximately 4 bar. The aerated mixture was mixed through one orifice plate of 1 mm and further mixed in the pump to give an overrun of approx. 100% at atmospheric pressure once dispensed.

[0096] The beverage had an ice-fraction of 12% by mass measured using the cafetiere method

[0097] When left without disturbance the beverage remained substantially foamed (approx. s of the beverage) and ice remained within the beverage for more than 30 minutes. The beverage has a smooth creamy texture not unlike that found in dairy-product-containing beverages. The ice crystals do not clump and can be drunk through a straw, giving an interesting mouth feel.

[0098] As demonstrated in these examples, the claimed method provides a novel beverage for the consumer. In particular, it has the refreshment of a cold beverage without a grainy or rough icey structure. Instead, the fine bubble and ice-crystal structure results in a creamy mouthfeel, despite the absence of dairy fats or the like. Thus, the inventors have been able to provide a healthy ice beverage with a rich texture.

[0099] Although preferred embodiments of the invention have been described herein in detail, it will be understood by those skilled in the art that variations may be made thereto without departing from the scope of the invention or of the appended claims.