IRON FORTIFIED TEA-BASED BEVERAGE

Abstract

The present invention provides a product comprising: a) a tea component, b) FeNaEDTA; and c) di-basic NaPP.

Claims

1. A product comprising: a) a tea component, b) ethylenediaminetetraacetic acid, ferric-sodium salt (FeNaEDTA); and c) di-basic sodium pyrophosphate (NaPP).

2. The product according to claim 1, wherein the product is a beverage precursor.

3. The product according to claim 1, wherein the tea component is derived from the plant Camellia sinensis.

4. The product according to claim 1, wherein the tea component is black tea.

5. The product according to claim 1, wherein the tea component is green tea.

6. The product according to claim 1, wherein the tea component is leaf tea.

7. The product according to claim 1, wherein the product comprises from 90 to 99.9% by dry weight of the tea component.

8. The product according to claim 1, wherein the product comprises from 0.05 to 10% by dry weight of FeNaEDTA.

9. The product according to claim 1, wherein the product comprises from 0.05 to 10% by dry weight of di-basic NaPP.

10. The product according to claim 1, wherein the product comprises a molar ratio of di-basic NaPP:FeNaEDTA of from 0.5:1 to 4:1.

Description

DETAILED DESCRIPTION OF THE INVENTION

Product

[0031] The present invention relates to an iron fortified product comprising a tea component. The product of the invention encompasses ready-to-drink teas including bottled tea-based beverages such as iced tea, leaf-based beverage products, ready to drink formats, water soluble tea powders or granules, or liquid tea beverages.

[0032] The invention is particularly directed towards beverage precursor products—that is to say, products in which tea is provided in a dry format to which water will be added by the consumer. The tea component may therefore be tea leaves to be brewed, or tea powder to be dissolved, or tea granules to be dissolved, or a combination thereof.

Tea Component

[0033] For the purpose of the present invention, “tea” means material from Camellia sinensis var. sinensis and/or Camellia sinensis var. assamica. The term “leaf tea” refers to leaf and/or stem material from the tea plant in an uninfused form (i.e. material which has not been subjected to a solvent extraction step). In other words, the term “leaf tea” refers to the end product of tea manufacture (sometimes referred to as “made tea”).

[0034] As used herein, the term “black tea” refers to substantially fermented tea, wherein “fermentation” refers to the oxidative and hydrolytic process that tea undergoes when certain endogenous enzymes and substrates are brought together. During the so-called fermentation process, colourless catechins in the leaves and/or stem are converted to a complex mixture of yellow/orange to dark brown polyphenolic substances. For example, black leaf tea can be manufactured from fresh tea material by the steps of: withering, maceration, fermentation and drying. A more detailed description of the production of black tea can be found in Chapter 14 of “Tea: Cultivation to consumption” (edited by K. C. Wilson & M. N. Clifford, published in 1992).

[0035] The tea component of the present invention may therefore be derived from the plant Camellia sinensis. The tea component may be green tea or black tea. The tea component may be leaf tea, or tea extract, or tea powder. It is preferred that the tea component is leaf tea. More preferably, the tea component is black leaf tea or green leaf tea.

[0036] In order to deliver the organoleptic profile expected of a tea-based beverage, the required levels of polyphenols, or both, the product may comprise from 90 to 99.9% by dry weight of the tea component, more preferably from 92 to 99.75%, more preferably still from 94 to 99.5%, yet more preferably from 96 to 99.25%, most preferably from 98 to 99% by dry weight of the tea component.

[0037] The product may comprise from 0.5 g to 10 g of the tea component per portion, more preferably from 1 g to 7.5 g, more preferably still from 1.5 g to 5 g, most preferably about 2 g of the tea component per portion.

[0038] As used herein, the term “portion” means the amount of the product required for a single serving. In the case of ready to drink products, a portion will typically be a bottle or can of from 200 to 300 ml. For beverage precursor products (that is to say, products in which tea is provided in a dry format to which water will be added by the consumer), a portion is the amount of the beverage precursor product that is required to make the drink.

Iron Source

[0039] The product of the invention is fortified with Iron. Specifically, it is fortified with FeNaEDTA.

[0040] FeNaEDTA has the CAS number 15708-41-5, formula C.sub.10H.sub.12N.sub.2O.sub.8FeNa, and the following structure:

##STR00001##

[0041] Synonyms of FeNaEDTA include: Iron(III) sodium EDTA; Ferric Sodium EDTA; Ethylenediaminetetraacetic Acid, Ferric-Sodium Salt; FeNa-EDTA; sodium iron(III) EDTA; Ferrazone; and Sodium feredetate.

[0042] As stated, thanks to the present invention the product is able to provide high levels of iron fortification without suffering from darkening or colour change. The product may therefore comprise from 0.05 to 10% by dry weight of FeNaEDTA, more preferably from 0.1 to 7.5%, more preferably still from 0.2 to 5%, yet more preferably from 0.3 to 2.5%, yet more preferably still from 0.5 to 1%, most preferably from 0.6 to 0.7% by dry weight of FeNaEDTA.

[0043] The product may comprise from 0.5 to 100 mg of FeNaEDTA per portion, more preferably from 1 to 75 mg, more preferably still from 2.5 to 50 mg, yet more preferably from 5 to 25 mg, yet more preferably still from 7.5 to 20 mg, most preferably from 10 to 15 mg of FeNaEDTA per portion.

[0044] The CODEX Alimentarius of the World Health Organisation states a Nutrient Reference Value (NRV) of 22 mg of Iron for diets rich in plant foods (such as those mainly consumed in India). Due to the presence of the colour corrector, the product may comprise high levels of iron without suffering darkening or colour change. The product may therefore comprise from 1 to 50% of the aforementioned NRV of iron per portion, preferably from 2 to 35%, more preferably from 5 to 20%, more preferably still from 7.5 to 15%, most preferably about 10% of the NRV of iron per portion.

[0045] The product may comprise from 0.2 mg to 10 mg iron per portion, preferably from 0.5 mg to 7.5 mg, more preferably from 1 mg to 5 mg, more preferably still from 1.5 to 4 mg. Most preferably, the product comprises about 2 mg of iron per portion.

[0046] For the avoidance of doubt, when iron per se is stated as a mass amount it refers to the amount of iron as such in the product portion, not the iron source. For example, 2.1 mg of iron means 2.1 mg of the Fe ion, it does not mean 2.1 mg of FeNaEDTA.

Colour Corrector

[0047] The product of the invention employs a colour correcting component to prevent the darkening and colour changes that can surprisingly be caused when FeNaEDTA is provided in a tea-based product. The invention employs di-basic NaPP for this purpose.

[0048] Di-basic NaPP has the CAS number 7758-16-9, the formula Na.sub.2H.sub.2P.sub.2O.sub.7, and the following structure:

##STR00002##

[0049] Synonyms of di-basic NaPP include: Disodium diphosphate; Disodium pytophosphate; Disodium dihydrogen pyrophosphate; Sodium acid pyrophosphate; and Sodium polyphosphate.

[0050] The product may comprise from 0.05 to 10% by dry weight of di-basic NaPP, more preferably from 0.1 to 7.5%, more preferably still from 0.2 to 5%, yet more preferably from 0.3 to 2.5%, yet more preferably still from 0.5 to 1%, most preferably from 0.8 to 0.9% by dry weight of di-basic NaPP.

[0051] The product may comprise from 1 to 100 mg of di-basic NaPP per portion, more preferably from 2.5 to 75 mg, more preferably still from 5 to 50 mg, yet more preferably from 7.5 to 30 mg, yet more preferably still from 10 to 25 mg, most preferably from 15 to 20 mg of di-basic NaPP per portion.

Molar Ratio of Colour Corrector:Iron Source

[0052] The product may comprise a molar ratio of di-basic NaPP:FeNaEDTA of from 0.5:1 to 4:1, preferably from 0.75:1 to 3.5:1, more preferably from 1:1 to 3:1, more preferably still from 1.5:1 to 2.5:1, most preferably about 2:1.

[0053] As set out in the foregoing, the present invention has found that the use of the claimed combination of Iron Source and Colour Corrector is capable of correcting darkening and colour changes associated with iron fortified of tea-based beverages.

[0054] Darkness and Overall Colour Correction Factors

[0055] The colour and darkness of tea-based beverages can be expressed using the coordinates of the CIE 1976 L*a*b* colour space. CIE L*a*b* values can be measured by colourimetry according to the joint ISO/CIE standard (ISO 11664-4:2008(CE); CIE S 014-4/E:2007). Colour is expressed as three values: [0056] L* for the lightness from black (0) to white (100), [0057] a* from green (−) to red (+), and [0058] b* from blue (−) to yellow (+).

[0059] Samples can be compared to one another to determine the difference in these values (ΔL*, Δa*, Δb*) and from these values, the total colour difference, Delta E* (ΔE*) can also be calculated.

[0060] It will be appreciated that the ΔL* and ΔE* values are of particular interest in the context of the present invention because they may be used to determine the darkness and colour respectively of a normal, un-fortified tea-based beverage and compare that to tea-based beverages containing various Iron Sources and Potential Colour correctors.

[0061] The present invention seeks to provide a product that delivers an iron-fortified tea-based beverage that utilises di-basic NaPP to correct the darkness and overall colour changes caused by FeNaEDTA such that the darkness and overall colour is as close as possible to the non-fortified tea-based beverage. This can be represented as “Darkness Correction Factor” (DCF) and Overall Colour Correction Factor” (OCCF) respectively.

[0062] DCF is calculated as:

DCF=L*.sub.sample−L*.sub.blank [0063] where L*.sub.sample is the L*.sub.value of the fortified and colour corrected tea-based beverage obtained from the product according to the present invention; and [0064] where L*.sub.blank is the L*.sub.value of the same tea product with only the tea component and no iron source or colour corrector.

[0065] Accordingly, the DCF value is preferably from −10 to 0, more preferably from −8 to 0, more preferably still from −6 to 0, yet more preferably from −4 to 0, most preferably from −2.5 to 0.

[0066] OCCF is calculated as:

OCCF=E*.sub.sample−E*.sub.blank [0067] where E*.sub.sample is the E*.sub.value of the fortified and colour corrected tea-based beverage obtained from the product according to the present invention; and [0068] where E*.sub.blank is the E*.sub.value of the same tea product with only the tea component and no iron source or colour corrector.

[0069] Accordingly, the OCCF value is preferably from 0 to 10, more preferably from 0 to 8, more preferably still from 0 to 6, yet more preferably from 0 to 4, most preferably from 0 to 2.5.

[0070] As used herein the term “comprising” encompasses the terms “consisting essentially of” and “consisting of”. All percentages and ratios contained herein are calculated by weight unless otherwise indicated. It should be noted that in specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount.

[0071] Except in the operative and comparative examples, all numbers in the description indicating amounts of materials, conditions of reaction, physical properties of materials, and/or use are to be understood as being preceded by the word “about”.

[0072] The various features of the embodiments of the present invention referred to in individual sections above apply, as appropriate, to other sections mutatis mutandis. Consequently, features specified in one section may be combined with features specified in other sections as appropriate. The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art in the field of tea processing.

[0073] The present invention will now be illustrated by reference to the following non-limiting examples.

Examples

[0074] Various sources of iron were assessed for their impact on the colour and darkness of tea beverages. The ability of various compounds to correct these colour changes was also tested.

Materials

[0075] The tea beverages tested were: [0076] Black Tea teabags, Lipton Yellow label (purchased from Albert Hein supermarket, NL) [0077] Total amount of black tea: 2 g [0078] Green Tea teabags, Lipton Greentea classic (purchased from Albert Hein supermarket, NL) [0079] Total amount of green tea: 2 g

[0080] The Iron Sources tested were: [0081] FeNaEDTA (Trihydrate, CAS number 18154-32-0) [0082] Supplier: Dr. Paul Lohmann GmbH & Co. KGaA, Hauptstrasse 2, 31860 Emmerthal, Germany [0083] Ferrous Fumarate (FeFu) (CAS number 141-01-5) [0084] Supplier: Aldrich, order number F5381, lot number SLBB5910V [0085] FeSO.sub.4 (Heptahydrate, CAS number 7782-63-0) [0086] Supplier: Sigma-Aldrich, product number 215422, lot number MKBS1888V

[0087] The Potential Colour Correctors tested were: [0088] Di-basic NaPP (CAS number: 7758-16-9) [0089] Supplier: Innophos Canada Holdings (sodium acid pyrophosphate) Product name: BP Pyro [0090] Tetra-basic NaPP (CAS Number: 7722-88-5) [0091] Supplier: Innophos Canada Holdings

Sample Preparation

Iron Sources—Stock Solutions:

[0092] For Iron Source solutions, 10 mg Fe/ml stock solutions were prepared using the Iron Sources listed above. The 10 mg Fe/ml solutions (equivalent to 0.169 mol/I) were prepared from the iron salts where: [0093] FeNaEDTA was FeNaEDTA*3H.sub.2O containing 15.2 wt % Fe [0094] FeSO.sub.4 was FeSO.sub.4*7H.sub.2O containing 20.1 wt % Fe, and [0095] FeFu contained 32.9 wt % Fe.

Potential Colour Correctors—Stock Solutions:

[0096] For Tetra-basic NaPP, 72 mg Tetra-NaPP/ml stock solutions were prepared. [0097] For Di-basic NaPP, 59.4 Di-NaPP mg/ml stock solutions were prepared.

Tea Beverages:

[0098] Green and Black Tea Beverages were prepared separately as follows: [0099] 200 ml of boiled milli-Q water was transferred to a plastic jar with the tea bag (green or black tea). [0100] At the point of contact (water to tea bag) a timer was started, the bag was infused for 3 minutes. [0101] After the 3 minute infusion, the tea bag was gently squeezed using a spoon, removed, and discarded. [0102] Where used, aliquots of the stock solutions of Iron Sources and/or Potential Colour Correctors described above were stirred into the brewed Tea Beverage to provide the Test Combinations as described below and in Tables 1 & 2. [0103] The brewed Tea Beverages were allowed to cool for 10 minutes. [0104] The cooled Tea Beverages were stirred before colorimetric analysis as described below.

Test Combinations:

[0105] Samples were prepared as shown in Tables 1 & 2. All samples contained 200 ml of the Tea Beverage solutions brewed from the 2 g of tea in the bags described above.

[0106] Where Iron Sources were added, stock solution was added in an amount that provided 9.5% of the aforementioned NRV of Iron—i.e. 2.1 mg of Iron (Fe) in the 200 ml Tea Beverage solution.

[0107] Where Potential Colour Correctors were used, stock solution was added in an amount to provide a molar ratio of 2.1:1 of Potential Colour Corrector:Iron Source. For those Test Combinations where no Iron Source was present, the amount of Potential Colour Corrector was added such that it would have been equivalent to a molar ratio of 2.1 relative to the 15% RDA of the Iron Source, if the Iron Source had actually been present.

[0108] Samples that contained both FeNaEDTA and dibasic NaPP contained: [0109] 13.8 mg (0.68% wt) FeNaEDTA*3H.sub.2O per cup of tea, equivalent to 12 mg of FeNaEDTA anhydrous. [0110] 17.5 mg (0.86% wt) dibasic NaPP per cup of tea (Equivalent to 2.1 equimolar FeNaEDTA).

TABLE-US-00001 TABLE 1 Sample Preparation and Results of Colorimetric Analysis for Black Tea Equivalent Molar Ratio Potential Sample % NRV Potential Colour Tea Iron Colour Name pH Fe Corrector:Fe Used Source Corrector ΔE* ΔL* Black_1 4.8 9.5 2.1 Black FeNaEDTA Di-basic NaPP 2.2 −2.1 Black_Blank 5.1 0 n/a Black none none 0 0 Black_A 4.8 9.5 n/a Black FeFu none 12.4 −9.5 Black_B 4.8 9.5 2.1 Black FeFu Di-basic NaPP 5.8 −3.3 Black_C 5.5 9.5 2.1 Black FeFu Tetra-basic NaPP 12 −9.2 Black_D 5 9.5 n/a Black FeNaEDTA none 6.1 −5.1 Black_E 5.6 9.5 2.1 Black FeNaEDTA Tetra-basic NaPP 15.7 −13.2 Black_F 4.5 9.5 n/a Black FeSO4 none 37.7 −27.9 Black_G 4.4 9.5 2.1 Black FeSO4 Di-basic NaPP 16.9 −11.1 Black_H 4.7 0 2.1 Black none Di-basic NaPP 2.3 1.4 Black_I 5.7 0 2.1 Black none Tetra-basic NaPP 1.7 −0.2 Black_J 5.3 9.5 2.1 Black FeSO4 Tetra-basic NaPP 39.1 −29

TABLE-US-00002 TABLE 2 Sample Preparation and Results of Colorimetric Analysis for Green Tea Equivalent Molar Ratio Potential Sample % NRV Potential Colour Tea Iron Colour Name pH Fe Corrector:Fe Used Source Corrector ΔE* ΔL* Green_1 5 9.5 2.1 Green FeEDTA Di-basic NaPP 2.7 −1.4 Green_Blank 5.4 0 n/a Green none none 0 0 Green_A 5.1 9.5 n/a Green FeFu none 6.4 −5.7 Green_B 4.9 9.5 2.1 Green FeFu Di-basic NaPP 4.3 −2.1 Green_C 6.1 9.5 2.1 Green FeFu Tetra-basic NaPP 8.3 −8 Green_D 5.3 9.5 n/a Green FeEDTA none 5.6 −5.3 Green_E 5.9 9.5 2.1 Green FeEDTA Tetra-basic NaPP 15 −14.5 Green_F 4.7 9.5 n/a Green FeSO4 none 31 −27.4 Green_G 4.7 9.5 2.1 Green FeSO4 Di-basic NaPP 12.4 −9.4 Green_H 5.1 0 2.1 Green none Di-basic NaPP 3.5 0.7 Green_I 6.3 0 2.1 Green none Tetra-basic NaPP 6.3 −1.3 Green_J 5.7 9.5 2.1 Green FeSO4 Tetra-basic NaPP 35.1 −23.6

Colorimetric Analysis

[0111] Aliquots of 20 ml of each of the Samples shown in Tables 1 & 2 were transferred to a quartz cuvette and CIE L*a*b* analysis was performed as follows.

[0112] The colours of the samples were measured using a Hunterlab Ultrascan VIS spectrophotometer (wavelength: 360-780 nm). For this work transmitted colour was measured.

[0113] The sensor used a plastic integrating sphere that was six inches (152.4 mm) in diameter and coated with Spectraflect™, to diffuse the light from the lamp. The light illuminated the sample and was transmitted through it. A lens was located at an angle of 8° from perpendicular to the sample surface. The lens collected the transmitted light and directed it to a diffraction grating which separated the light into its component wavelengths which were measured by dual diode arrays and converted into data.

[0114] The transmission compartment located in the middle of the sensor was used for measuring the transmitted colour of the liquids. The transmission compartment door was closed while standardizing and taking measurements. A transmission cell holder accommodated aliquots in 10 mm transmission cells. To install, the transmission cell holder was placed into the transmission compartment at the centre, widest part of the transmission compartment.

[0115] The transmission cell provided an optically clear glass cell with a fixed path length of 10 mm. Its dimensions were 55 mm×57 mm (width×height). The minimum sample volume for measurement was 20 ml. Measurements were done in total transmission mode (TTRAN). The cell was placed at the sphere opening at the front of the transmission compartment, inside the spectrophotometer.

Measurements

[0116] The spectrophotometer was controlled by EasyMatch QC software which performed integration of transmittance values over the visible spectrum to arrive at tristimulus X, Y, and Z values. These values simulate the colour matching response functions of the human observer as defined by the 1931 2° Standard Observer or the 1964 CIE 10° Standard Observer (CIE XYZ).

Instrument Settings

[0117] Sensor name: USVIS1666—Ultrascan VIS [0118] ModeType: TTRAN—Total Transmission [0119] Area View: 1 in. [0120] UV filter position: UVF nominal

Calculation of ΔE*, and ΔL*

[0121] Calculation of ΔE* and ΔL* made use of the L*a*b* values as calculated by the Hunterlab software.

Calculation Δa* and Δb*:

Δa*=a*.sub.sample−a*.sub.blank

Δb*=b*.sub.sample−b*.sub.blank

Calculation ΔL*:

ΔL*=L*.sub.sample−L*.sub.blank

[0122] ΔL* indicates difference in lightness and darkness (+ΔL* means sample is lighter than the “blank” sample, −ΔL* means sample is darker than the “blank” sample)

Calculation ΔE*:

ΔE*=√{square root over ((ΔL*).sup.2+(Δa*).sup.2+(Δb*).sup.2)}

[0123] Deltas for L* (ΔL*), a* (Δa*) and b* (Δb*) indicate how much a sample and the “blank” sample differ from one another in L*, a* and b*. ΔL*, Δa* and Δb* may be positive (+) or negative (−). The total colour difference, Delta E* (ΔE*), however, is always positive.

pH Measurement

[0124] 25 ml of samples were aliquoted in a 50 ml tube, stored for 1-2 days in the refrigerator, pH was then measured (with an InLab Expert Pro electrode) in samples at approximately 16° C. with a pH meter (Mettler S20 SevenEasy pH) which corrected for temperature. The pH values are shown in Table 1.

Visual Assessments

[0125] 200 μl of each sample was transferred to a well of a 96-well plate and photos were taken.

Results of Colorimetric Analysis

[0126] The results of the Colorimetric Analysis are provided in the final columns of Tables 1 & 2. [0127] ΔE* shows the change in colour relative to the respective “blank” sample. [0128] ΔL* shows whether the tea is showing darkening (negative figure) or lightening (positive figure) compared to the “blank” sample.

[0129] It can be seen that when used without a Potential Colour Corrector, all Iron Sources (FeFu, FeNaEDTA, FeSO.sub.4) caused changes in colour and darkening (See results for Samples: Black_A, Black_D, Black_F, Green_A, Green_D, Green_F).

[0130] It can also be seen that when the Potential Colour Correctors were used without an Iron Source, all samples experienced some minor changes in colour and darkening (See results for Samples: Black_H, Black_I, Green_H, Green_I).

[0131] Crucially, it can be seen that only the di-basic NaPP proved to be effective at correcting the colour changes and darkening but only for one Iron Source—i.e. FeNaEDTA (See results for Samples: Black_1, and Green_1).

[0132] The inventors have therefore identified the unique ability of the combination of FeNaEDTA and di-basic NaPP to provide an iron fortified tea-based beverage that does not suffer from colour change or from darkening (irrespective of whether the tea is green or black).