CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of European Application No. 22182131.7, filed June 30, 2022, U.S. which is incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates to a process for preparing a thermally inhibited (TI) bleached starch, to a thermally inhibited bleached starch obtained by said process, and uses thereof. In particular, the present invention relates to a process for preparing a TI bleached starch with an excellent balance between rheological properties and color. TI bleached starches are useful in food applications.

BACKGROUND OF THE INVENTION

[0003] In general, unmodified starches can be heated to below their gelatinization temperature, in water or in an aqueous solution, to form a slurry. When heated above their gelatinization temperature said starches typically form a paste. Upon exposing the slurry to heat, the starch contained therein becomes hydrated, it gelatinizes and swells increasing the viscosity of the slurry. This process is desirable when manufacturing food applications. However, exposure of the starch to heat, shear, rapid movement, extreme pH, or other harsh conditions may cause the hydrated and swollen starch to degrade resulting in a reduction in the viscosity, which is typically undesirable.

[0004] To restrict the over-swelling and to prevent the degradation of the starch, a thermal inhibition process can be applied to the starch, to obtain a thermally inhibited starch (TI starch). Thermal inhibition causes interactions, e.g. cross-linking, between molecules in the starch, thereby allowing the resultant thermally inhibited starch to have an increased resistance to heat, shear, or high/low pH conditions. Thermal inhibition allows the optimal swelling of the starch to achieve the appropriate prolonged viscosity profile without overswelling the starch, which would lead to a breakdown in the viscosity profile. In addition, thermal inhibition is a clean process since no undesirable chemicals are necessary to inhibit the starch. However, when performed under alkaline conditions (also known as alkaline roasting), thermal inhibition tends to darken the color of the starches to a brown or amber color, which in turn may deleteriously impact the color of the finished food product.

[0005] Bleaching, with e.g. chlorine-bleaching agents, can be used to obtain (near) white starches. WO2018112383A1 discloses inhibiting starches in alcoholic solution with a base or salt treatment agent and an additional step of bleaching using chlorine-based bleaching agents. The disadvantage of using chlorine-bleaching agents is that it might leave residual chemicals, off-tastes, and odors while having a negative impact on the rheological properties of the starch.

[0006] Consumers often prefer products which contain less or no chemically processed ingredients. Hence, there is a need among food manufacturers for little or no chemically processed ingredients, preferably without any off-taste or off-odor and having the optimum combination of properties, e.g. rheological, color and the like.

[0007] The present inventors surprisingly discovered that whitened, thermally inhibited starches can be produced with a simple process, without substantially impacting the viscosity of the thermally inhibited starch, by using potassium permanganate as a bleaching agent. An objective of the present invention is to produce thermally inhibited starches with good color value (white or near white color) that are free from crosslinking chemicals, and essentially free of chemical tastes and odors. Another objective of the present invention is to produce (near) white, thermally inhibited starch which have been subjected to minimal chemical processing. Another object of the present invention is to bleach thermally inhibited starches such that optimal color values are obtained while maintaining the rheological parameters, e.g. viscosity, of the TI starches to a maximum extent. It is thus an object of the present invention to find an optimal balance between good color values and good viscosity parameters for TI starches.

[0008] The present invention addresses these problems and provides TI starches with good color values that are free from crosslinking chemicals and free of chemical tastes and odors.

SUMMARY OF THE INVENTION

[0009] The invention relates to a process for preparing a thermally inhibited (TI) bleached starch, comprising the steps of: i) thermally inhibiting a starch to obtain a thermally inhibited (TI) starch; ii) preparing a slurry of the TI starch in water; iii) adding between 0.01 and 0.2 wt.% (weight %) of potassium permanganate (KMnOr), based on the dry weight of the TI starch, to the slurry; iv) adjusting the pH of the slurry to a value between pH 3.0 and pH 9.0, preferably between pH 3.5 and pH 4.5, before, during, and/or after the addition of the potassium permanganate; v) agitating the slurry for a period of time sufficient to obtain a TI bleached starch slurry; vi) neutralizing the TI bleached starch slurry by adding a neutralizing agent; vii) optionally washing the slurry; and viii) dewatering the slurry to obtain a TI bleached starch; wherein said TI bleached starch obtained has a colorimetric parameter b that is decreased towards 0 by at least 1.5 units, preferably at least 3 units, more preferably at least 4 units, compared to the value of the TI starch prior to bleaching; wherein said TI bleached starch obtained has a colorimetric parameter L that is increased towards 100 by at least 2 units, preferably at least 4 units, more preferably at least 6 units, compared to the value of the TI starch prior to bleaching.

[0010] In another aspect, the invention relates to a TI bleached starch directly obtained by the method according to the invention having a colorimetric parameter b of from 0 to +9.0, preferably 0 to +4.5, more preferably from 0 to +3.0, even more preferably from 0 to +2.6 and having a colorimetric parameter L of from 91 to 100 L, preferably from 96 to 100 L.

[0011] In another aspect, the invention relates to a use of the TI bleached starch directly obtained by the method according to the invention or according to the above aspect in a food product, preferably selected from the group consisting of drinks, daily' products, fat-food products, dressings, condiments, confectionery fillings, more preferably selected from the group consisting of confectionery fillings, white dairy products, and mayonnaise style dressings.

[0012] Below several preferred features are disclosed. These features are applicable to the process as well as to the other aspects. Advantageously, the present invention discloses a white or near white, thermally inhibited bleached starch and a method of forming a white or near white thermally inhibited bleached starch.

DETAILED DESCRIPTION [0013] The present invention is elucidated below with a detailed description, with headings for each of the important features of the present invention or steps of the method. When used in this specification and claims, the terms "comprises", “having”, and "comprising" and variations thereof mean that the specified features, steps, or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps, or components. It must also be noted that as used herein and in the claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

Starch starting material

[0014] The first step in the process of the invention is thermally inhibiting a starch. Starch is a semicrystalline biopolymer made up of anhydro glucose units linked by a-(l,4) and a-(l,6) glycosidic bonds. The major components are amylose and amylopectin that differ in molecular size and degree of branching. Typically starch has a natural pH of about 4.0 to about 6.0.

[0015] The starch used in the present invention may be any starch derived from any native source, viz. a native starch. “Native starch” as used herein, is a starch as it is found in nature, for example from plants.

[0016] The starch used may be any granular starch in raw or modified form. Preferably, the starch is in its raw, non-modified form, i.e. it is a native starch. Preferably, the starch is a non-pregelatinized starch. The starch is preferably a non-chemically modified starch.

[0017] The starch is preferably selected from starch from cereals, tubers and roots, legumes (including pea, chick pea, lentils, fava beans, lupin bean, and mung bean) and fruits. The starch can be corn starch, potato starch, sweet potato starch, barley starch, wheat starch, rice starch, sago starch, Kudzu starch, amaranth starch, tapioca (cassava) starch, arrowroot starch, canna starch, pea starch, banana starch, quinoa starch, oat starch, rye starch, millet starch, triticale starch and sorghum starch, as well as low amylose (waxy) and high amylose varieties thereof. “Low amylose variety” or “waxy” or “waxy variety” is intended to mean a starch containing at most 10% amylose by weight; optionally, at most 5%; optionally, at most 2%; optionally, at most 1% amylose, all by weight of the starch. Amylose-free waxy starches contain essentially 100% by weight amylopectin. “High amylose varieties” is intended to mean a starch which contains: at least 30% amylose; optionally, at least 50% amylose; optionally, at least 70% amylose; optionally, at least 80% amylose; optionally, at least 90% amylose, all by weight of the starch. The starch is more preferably selected from the group consisting of waxy corn starch, waxy potato starch, waxy tapioca starches, and one or more combinations thereof.

Thermal inhibition of starch

[0018] One step in the process of the invention is thermal inhibition of a starch to obtain a TI starch.

[0019] Thermal inhibition can be effected with any known means in the art. Thermal inhibition of starch may comprise the steps of: i) alkaline treatment; ii) dehydrating the starch until it is anhydrous, or substantially anhydrous; and iii) heat-treating at a temperature and a period of time to result in inhibition.

[0020] “Thermal inhibition” refers to a process that heats (non-)gelatinized, dehydrated starch in a manner that inhibits the starch, e.g. having a higher tolerance to processing variables such as heat, shear and pH extremes while maintaining functionality that is similar to a chemically cross-linked starch. “Thermally inhibited starch” refers to a starch that has undergone a treatment at high temperature in a dehydrated alkaline state to form a starch that is functionally similar to a chemically cross-linked starch but which has a high tolerance to processing variables such as heat, shear and pH extremes.

[0021] Dehydration forms an anhydrous, or essentially anhydrous, starch. In one nonlimiting example of dehydrating the starch, the starch is suspended in water to form a slurry. Preferably, the slurry comprises the starch at from 30 to 40 wt .%. Alternatively, the starch may be present at a higher content (for example from 60 wt.% or greater), or the starch may be present at a lower content (for example from 25 wt.% or lower). The pH of the slurry may adjusted to from 8 to 11 using an alkaline source. Alkaline treatment may also be completed by other known methods in the art. Examples of suitable alkaline sources include sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)z), sodium carbonate (Na2CO3) and/or potassium carbonate (K2CO3).

[0022] The slurry is then dewatered and dried. Initial dewatering of the slurry may be performed at a temperature of from 65 °C to 75 °C, and for a period of time sufficient until the moisture level of the starch is e g. between 10 wt.% to 14 wt.%. The dewatered starch may be further dehydrated at a temperature of between 100 °C to 155 °C, and for a time period sufficient to render the starch anhydrous or mostly anhydrous. The mostly anhydrous starch has a moisture content of: 5 wt.% or less; optionally, a moisture content of 2 wt.% or less; optionally, a moisture content of 1 wt.% or less. [0023] Typically, dehydration of the starch is completed by heat treatment. However, dehydration of the starch can be completed by any means known in the art. Examples of dehydration include but are not limited to thermal dehydration and non-thermal dehydration techniques.

[0024] Typically, the temperature of the heat treatment is from 140 °C to 180 °C, preferably from 150 °C to 170 °C. Typically, the period of time for heat treatment is from 0.5 to 20 hours (30 to 1200 minutes), preferably from 0.5 to 5 hours (30 to 300 minutes).

[0025] The thermal inhibition may be carried out in an oxygen enriched or an oxygen depleted atmosphere. Preferably, the oxygen concentration is at least 4 moles/m ³ , such as at least 6.5 moles/m ³ , such as at least 9 moles/m ³ .

[0026] In one non limiting example of forming a thermally inhibited starch, a starch and water slurry is prepared, wherein the starch comprises about from 30 to 40 wt.% of the slurry, the balance being water. The pH of the slurry is adjusted to from 8.0 to 11.0 using any alkaline source, for example sodium carbonate. The slurry is then dewatered and dried. Subsequently, the dewatered materials is dehydrated at a temperature of from 100 °C to 155 °C for a time sufficient to render the starch anhydrous or substantially anhydrous, and preferably having a content of less than 0.5 wt.% moisture. Next, the starch is heated to a temperature ranging from 140 °C to 180 °C, and in some aspects from 150 °C to 170 °C, for a period of time ranging from 0.5 to 20 hours, and preferably from 0.5 to 5 hours, to achieve thermal inhibition.

[0027] The TI starch obtained may have a moisture content of less than 1.8 wt.%, preferably less than 1.6 wt.%, more preferably less than 1.4 wt.%, even more preferably less than 1.2 wt.% or even less than 1.0 wt.%, or less than 0.5 wt.%.

[0028] The TI starch (non-bleached) obtained may have a b value that is increased by (up to) 7 units during the thermal inhibition. The TI starch may have a b value that is above 6, such as above 8, such as above 9. The TI starch obtained may have a L value that is increased by (up to) 13 units during the thermal inhibition. The TI starch may have a L value that is below 92, such as below 90, or even below 88.

[0029] The viscosity of the TI starch (non-bleached) may vary widely based on the type of starch used.

[0030] The degree to which a starch is thermal inhibited can be altered by varying the conditions of the thermal inhibition. The resultant starch is typically known as a low, medium or high thermally inhibited starch. The level of inhibition can be verified by using RVA viscosity analysis. For example, varying the level of dehydration, the method of dehydration, the conditions of the dehydration, the method of alkaline treatment, the conditions of the alkaline treatment, the pH of the alkaline treatment, the thermal inhibition temperature, the length of time the starch is thermally inhibited, the rate of air flow, the air to mass ratio, the presence of inducers including starch derivatives or non-starch derivatives and other conditions of the thermal inhibition such as pressure and different gaseous environment alters the degree of thermal inhibition.

Optional intermediate step of washing

[0031] The process of the invention may comprise an additional step of washing and dewatering the TI starch obtained prior to the bleaching step. The washing step comprises the addition of a certain amount of water to the TI starch and optionally agitating; and then dewatering the washed TI starch. The dewatering may comprise a step of filtration or centrifugation (e.g. removal of the majority of the water) and in addition, it may optionally also comprise a drying step, e.g. by flash drying. It is possible that more than one washing step is applied. The washing may be carried out by convention means and equipment, e.g. in a (multistage) washing battery

Preparation of a slurry in water

[0032] One step in the process of the invention is preparing a slurry of the TI starch in water.

[0033] “Slurry” refers to a mixture of starch in water formed by heating the starch in water to below the gelatinization temperature. The formation of the slurry may be carried out by heating the starch in water to a temperature of between 15 and 50 °C, such as between 20 and 40 °C. The preparation of a slurry may be carried out according to normal practice, e.g. in a slurryfier.

[0034] Optionally, a slurry contains from 40 wt.% or less of starch; or, from 35 wt.% or less of starch; or, from 30 wt.% or less of starch; or, from 25 wt.% or less of starch; or, from 20 wt.% or less of starch; or, from 15 wt.% or less starch; or, from 10 wt.% or less of starch; or from 5 wt.% or less of starch; or, from 1 wt.% or less of starch.

[0035] The slurry that is prepared may have a dry solids (DS) content of between 30 and 40 wt.%, based on the total weight of the slurry. The slurry that is prepared may have a density of between 15 and 25 Baume (Be), preferably between 18 and 21 Be. These ranges provide an optimal compromise between the viscosity of the slurry (so that the slurry remains pumpable) and process efficiency (to minimize the amount of water that needs to be removed from the slurry).

Optional intermediate step of cooling the slurry

[0036] The process of the invention may comprise an additional step of cooling the slurry, preferably to a temperature of below 40 °C, more preferably below 30 °C, such as between 20 and 30 °C. Cooling may be carried out by conventional means and equipment.

Bleaching TI starch

[0037] According to the process of the invention the TI starch is bleached. During this bleaching step (i) a bleaching agent is added to the slurry, (ii) the pH of the slurry is adjusted before, during, and/or after the addition of the bleaching agent, and (iii) the slurry is agitated for a certain period of time to bleach the TI starch contained by the slurry.

[0038] According to the process of the invention, this phase comprises: iii) adding between 0.01 and 0.2 wt.% of potassium permanganate (KMnC ), based on the dry weight of the TI starch, to the slurry; iv) adjusting the pH of the slurry to a value between pH 3.0 and pH 9.0, preferably between pH 3.5 and pH 4.5, before, during, and/or after the addition of the potassium permanganate; and v) agitating the slurry for a period of time sufficient to bleach the TI starch contained by the slurry

[0039] The amount of potassium permanganate (KMnOi) used is between 0.01 and 0.2 wt.% based on the dry weight of the TI starch. If a lower amount is used, an insufficient bleaching effect might be obtained. If a too high amount is used, this may cause unwanted reactions, e.g. oxidation reactions degrading the starch. The aim of the present invention is to use as little amount as possible in order to achieve a process having as high efficiency as possible and using the lowest possible amount of chemicals.

[0040] The amount of potassium permanganate (KMnO4) that is added may be between 0.01 and 0.10 wt. %, preferably between 0.01 and 0.05 wt.%, more preferably between 0.01 and 0.03 wt.% based on the dry weight of the TI starch. Otherwise, the amount of potassium permanganate (KMnO4) that is added may be between 0.05 and 0.15 wt. % of based on the dry weight of the TI starch.

[0041] The pH adjustment of the slurry is preferably carried out before, during, or after the addition of the potassium permanganate, more preferably after the addition of the potassium permanganate. The pH of the slurry may be adjusted using an acid, such as hydrochloric acid, sulphuric acid or phosphoric acid. Most preferably, hydrochloric acid is used.

[0042] Preferably, the slurry is agitated during the bleaching step for a period of time of between 10 minutes and 60 minutes, preferably between 20 and 40 minutes. The temperature of the slurring during the agitation (during the bleaching step) may be between 20 and 40 °C.

Neutralizing TI bleached starch slurry

[0043] One step in the process of the invention is neutralizing the TI bleached starch slurry by adding a neutralizing agent. The neutralization agent used for neutralizing the slurry may be selected from the group consisting of sodium bisulfite, sodium metabisulfite, sodium sulfite, potassium bisulfite, potassium sulfite, sulfur dioxide gas, and one or more combinations thereof. Preferably, the neutralizing agent is sodium bisulfite. The quantity of neutralizing agent used should be sufficient to remove residual bleaching agent. The removal of the residual bleaching agent can be monitored by measuring the amount of SO2 in the slurry. Said amount may be quantified using SO2 strips from Supelco. These test strips indicate the amount (in mg/L) of SCH ² " which is in excess. There are several levels possible, e.g. a white test strip indicates 0 mg/L SO3 ² ” , whereas a dark red test strip indicates about 400 mg/L SO3 ² ". Other colors indicate levels in between these values, e.g. 10, 40, 80, and 180 mg/L SO3 ² ”. Preferably, neutralizer is added to achieve a level of between 10 and and 180 mg/L SO3 ² ”. In the final washing stage the remaining SO2 level preferably is less than or equal to 10 ppm.

[0044] The step of neutralizing the slurry by adding a neutralizing agent may also comprise adjusting the pH of the neutralized slurry to a value of between pH 4.0 and pH 5.5, preferably using an acid, more preferably hydrochloric acid (HC1). The pH adjustment is preferably carried out after the addition of the neutralizing agent.

Optional intermediate step of washing

[0045] One optional step in the process of the invention is washing the slurry containing the bleached TI starch after bleaching and prior to dewatering the slurry. Any washing method can be used, typical methods including adding water under agitation to the TI bleached starch. The amount of water is chosen to achieve the desired removal of the components that need to be washed away. The washing may be carried out using a (multistage) washing battery.

Dewatering the slurry

[0046] One step in the process of the invention is dewatering the slurry to obtain a

TI bleached starch.

[0047] Dewatering the slurry as used in the present claims and description may also include drying of the starch. Dewatering the slurry may comprise a step of filtering or centrifuging the TI bleached starch (that may be washed) from the slurry. Dewatering the slurry may comprise a step of filtering the TI bleached starch from the slurry and drying the TI bleached starch (that may be washed). The dewatering of the slurry may comprise drying of the slurry, preferably by flash drying, which may be carried out until reaching a moisture level in the bleached TI starch of at least 5 wt.%, preferably of between 10 and 15 wt.%.

Optional step of pregelatinizing the TI bleached starch

[0048] Preferably, after the washing of the slurry (if a step of washing is present) or after the dewatering of the slurry the TI bleached starch is pregelatinized to obtain a pregelatinized TI bleached starch. In an alternative process, an already pregelatinized starch may be used in the thermal inhibition step of the process.

[0049] However, most preferably, the method according to the invention uses a nonpregelatinized starch in the thermal inhibition step of the process and includes a pregelatinizing step after or during the dewatering step of the process.

[0050] The step of pregelatinizing may comprise cooking the TI bleached starch and drying the slurry, preferably to a moisture level of below 10 wt.%, or below 7 wt.% based on the total weight of the slurry. The cooking and drying can take place simultaneously (which is preferred) or sequentially, i.e. first cooking and then drying. The pregelatinization may be carried out under such conditions that the starch loses its granular structure due to swelling and bursting. Any known techniques may be used for pregelatinization and drying, such as drum drying, roll drying, spray drying, spray cooking, extrusion and jet cooking or combinations thereof.

Optional step of reducing the particle size of the TI bleached starch

[0051] The obtained TI bleached starch is preferably in the form of a powder. The size of the particles forming the powder can be adjusted using different means. Colorimetric parameters

[0052] The aim of the present invention is to provide thermally inhibited starches with good color value, in particular having a white or near white color. Perfect “white” refers to a starch that has the CIE L a b colorimetric values of L = 100, a = 0 and b = 0. The term “near white” refers to a starch that has CIE L a b colorimetric values close to these values (e.g. from 90 to 100 (L); from -1.0 to + 1.0 (a); and, from 0 to + 7 (b)). According to the process of the present invention, the TI bleached starches obtained have specific colorimetric parameters.

[0053] According to the present invention, the so-called L a b color scale is used. This L a b color scale (having colorimetric parameters L, a, and b) is based on the opponentcolors theory, which assumes that the receptors in the human eye perceive color as the following pairs of opposites: light-dark, red-green, and yellow-blue. The L value indicates the level of light or dark, the a value redness or greenness, and the b value yellowness or blueness. All three values are required to completely describe an object's color.

[0054] For the starches according to the present invention, the L value and the b value are important since these values may be negatively affected (L decreased and b increased) during the thermal inhibition step. For measuring the colorimetric values a Konica Minolta colorimeter device was used.

[0055] According to the process of the present invention, the TI bleached starch obtained has a colorimetric parameter b that is decreased towards 0 by at least 1.5 units compared to the value of the TI starch prior to bleaching. The TI bleached starch obtained may have a colorimetric parameter b that is decreased towards 0 by at least 3 units, preferably at least 4 units, or even by 6 units, compared to the value of the TI starch prior to bleaching.

[0056] According to the process of the present invention, the TI bleached starch obtained has a colorimetric parameter L that is increased towards 100 by at least 2 units compared to the value of the TI starch prior to bleaching. The TI bleached starch obtained may have a colorimetric parameter L that is increased towards 100 by at least 4 units, preferably at least 6 units, or even by at least 8 units, compared to the value of the TI starch prior to bleaching.

Viscosity parameters [0057] Another aim of the present invention is to obtain bleached TI starches with optimal color values while maintaining its viscosity as similar as possible to that of the thermally inhibited starch prior to bleaching.

[0058] During the thermal inhibition step, certain values for viscosity are obtained that are desirable. These viscosity values should be retained in the TI bleached product for as far as possible. Typically, during the known bleaching processes, the viscosity of the TI starches is negatively impacted. Preferably, the TI bleached starch has a viscosity which is essentially the same to that of the TI starch prior to bleaching.

[0059] A Rapid Visco Analyser (RVA) Newport scientific super 4 with the method disclosed below in the experimental section can be used to measure the viscosity profiles of TI bleached starches, as well as control starches. As used herein, the final viscosity of a sample refers to the viscosity at the end of an RVA run. The “final viscosity at neutral pH” in this description means the viscosity at the pH of deionized water. This is the final viscosity measured at the pH of the slurry that is obtained when the starch is slurried in deionized water. Generally, the pH of deionized water is between pH 6.0 and pH 6.4. The “final viscosity at pH 3” in this description means the viscosity at the pH of the slurry that is obtained when the starch is slurried in a pH 3 buffer.

[0060] In one non-limiting example of taking a viscosity measurement, the samples were suspended in deionized (DI) water or in a pH 3 buffer at 5.5 wt.% dry starch content (moisture corrected).

[0061 ] Preferably, the TI bleached starch of the present invention has a decrease in final viscosity, as measured neutral pH using a Rapid Visco Analyser, that is at most 20%, preferably less than 16%, compared to the viscosity of the TI starch prior to bleaching. It should be noted that in the present description “a decrease by less than” or “a decrease by at most” for viscosity means that the viscosity may also be the same (decrease of 0%) or even increased (a negative decrease).

[0062] Preferably, the TI bleached starch of the present invention has a decrease in final viscosity, as measured at pH 3 using a Rapid Visco Analyser, that is at most 30%, preferably less than 20%, compared to the viscosity of the TI starch prior to bleaching.

Specific aspects

[0063] With the process according to the present invention, different starting materials will provide different colorimetric parameters and final viscosities before and after bleaching. Below several specific non-limiting examples will be provided for the process of the present invention.

[0064] In a specific non-limiting example of the process of the invention:

* non-gelling waxy corn starch is used to obtain a thermally inhibited (TI) starch having a colorimetric parameter b that is at least 6.0, a colorimetric parameter L that is at most 92; and a final viscosity measured at neutral pH using a Rapid Visco Analyser using the method disclosed below in the experimental section that is between 1000 and 1400 cP;

* potassium permanganate (KMnOi) is added in an amount of between 0.01 and 0.10 wt. %, preferably between 0.01 and 0.05 wt.%, more preferably between 0.01 and 0.03 wt.% based on the dry weight of the TI starch, to the slurry; and

* a TI bleached starch is obtained having a colorimetric parameter b that is below 3.0, wherein b is decreased towards 0 by at least 2.0 units; a colorimetric parameter L that is at least 96, wherein L is increased by at least 1.0 unit; and a final viscosity at neutral pH that is between 1000 and 1400 cP, wherein the final viscosity' is decreased by at most 15%. in a specific non-limiting example of the process of the invention:

* non-gelling waxy corn starch is used to obtain a thermally inhibited (TI) starch having a colorimetric parameter b of at least 8.0, a colorimetric parameter L that is at most 90; and a final viscosity measured at neutral pH using a Rapid Visco Analyser using the method disclosed below in the experimental section that is between 650 and 950 cP;

* potassium permanganate (KMnCfi) is added in an amount of betw een 0.05 and 0.15 wt. % of based on the dry weight of the TI starch, to the slurry; and

* a TI bleached starch is obtained having a colorimetric parameter b that is at most 5.0, wherein b is decreased towards 0 by at least 2.0 units; a colorimetric parameter L that is at least 95.0, wherein L is increased towards 100 by at least 3.0 units; and a final viscosity at neutral pH that is between 650 and 950 cP, wherein the final viscosity is decreased by at most 6%.

TI bleached starch

[0065] The present invention also relates to a TI bleached starch having a colorimetric parameter b of from 0 to +9.0, preferably 0 to +4.5, more preferably from 0 to +3.0, even more preferably from 0 to +2.6 and that has a colorimetric parameter L of from 91 to 100 L, preferably from 96 to 100 L. Such TI starches have an optimal balance of color values, are free from crosslinking chemicals and free of chemical tastes and odors while having an excellent viscosity. Preferably, said TI bleached starch is directly obtained by the method according to the invention. Preferably, the TI bleached starch is pregelatinized.

Uses of the TI bleached starch

[0066] The present invention further relates to the use of the TI bleached starch in a food product. More particular, the present invention relates to the use of the TI bleached starch, even more preferably a pregelatinized TI bleached starch, in a food product selected from the group consisting of drinks, dairy products, fat-food products, dressings, condiments, confectionery fillings, more preferably selected from the group consisting of confectionery fillings, white dairy products, and mayonnaise style dressings.

[0067] Other non-limiting examples of food products which may include the TI bleached starch according to the present invention include luxury drinks, such as coffee, black tea, powdered green tea, cocoa, adzuki-bean soup, juice, soya-bean juice, etc.; milk component-containing drinks, such as raw milk, processed milk, lactic acid beverages, etc.; a variety of drinks including nutrition-enriched drinks, such as calcium-fortified drinks and the like and dietary fiber-containing drinks, etc.; dairy products, such as butter, cheese, yoghurt, low fat yoghurt, low protein yoghurt, sour cream, coffee whitener, whipping cream, custard cream, custard pudding, etc.; iced products such as ice cream, soft cream, lacto-ice, ice milk, sherbet, frozen yoghurt, etc.; processed fat food products, such as mayonnaise, margarine, spread, shortening, etc.; soups; stews; seasonings such as sauce, TARE (seasoning sauce), dressings such as Ranches dressing, dips, etc.; a variety of paste condiments represented by kneaded mustard; a variety of fillings typified by jam and flour paste; a variety or gel or paste-like food products including red bean -jam, jelly, and foods for swallowing impaired people; food products containing cereals as the main component, such as bread, noodles, pasta, pizza pie, com flake, etc.; Japanese, US and European cakes, such as candy, cookie, biscuit, hot cake, chocolate, rice cake, etc.; kneaded marine products represented by a boiled fish cake, a fish cake, etc.; live-stock products represented by ham, sausage, hamburger steak, etc.; daily dishes such as cream croquette, paste for Chinese foods, gratin, dumpling, etc.; foods of delicate flavour, such as salted fish guts, a vegetable pickled in sake lee, etc.; liquid diets such as tube feeding liquid food, etc.; supplements; and pet foods. These food products are all encompassed within the present invention, regardless of any difference in their forms and processing operation at the time of preparation, as seen in retort foods, frozen foods, microwave foods, etc. Preferably, the TI bleached starches, optionally pregelatinized, are used in convenience applications, such as soups, sauces, and gravies, in dairy applications, such as puddings, desserts, and drinks, in bakery applications or confectionary applications, such as in fillings, in fruit applications, and in meat & fish products.

Effects of the invention

[0068] The specific combination and sequence of process steps of the present invention allow for obtaining a TI bleached starch will all the benefits of the thermal inhibition process in view of viscosity properties without the negative side effects of an increase in yellow and/or tan color or off-taste or off-odor.

[0069] With the present invention it is possible to achieve effective bleaching of a thermally inhibited starch while maintaining a level of bleaching agent as low as possible. This has the advantage that the product obtained may be considered a clean label product. The present inventors have surprisingly found that with the process of the invention this low level of bleaching agent provides optimal viscosity parameters, good color values and in addition no bad taste or odor since no chlorine-based bleaching agent is used. It was unexpected that such good results would be obtained in view of both viscosity and color without the use of a chlorine-based bleaching agent or with the use of such low levels of bleaching agent.

[0070] Although certain aspects of the invention have been described, the scope of the appended claims is not intended to be limited solely to these specific aspects. The claims are to be construed literally, purposively, and/or to encompass equivalents. The scope of the present invention is defined by the appended claims. One or more of the objects of the invention are achieved by the appended claims.

EXAMPLES

[0071] The present invention is further elucidated based on the Examples below which are illustrative only and not considered limiting to the present invention. The following section outlines the starting materials and experimental techniques used in the examples.

Materials and methods

Materials [0072] Potassium permanganate, powder by Merck. Hydrochloric acid, 1 M solution by Fisher Chemical. Sodium hydroxide, 1 M solution by Fisher Chemical. Sodium metabisulfite, powder by Acros Organics. Sodium hypochlorite 150 g/L by Akzo Nobel Chemicals.

Determining moisture content

[0073] The moisture content of a sample was measured using a Sartorius MA 30 Moisture Analyser. A small amount of the sample (1.0 to 3.0 g) was weighed into the analyser. The analyser used determines the weight percentage moisture content through weight loss, and directly reports moisture content in percentage values.

Determining RVA viscosity

[0074] The viscosity of a sample was measured using a Newport scientific super model 4 Rapid Visco Analyser (RVA). Each sample was suspended in deionized water or buffer pH 3.0 at 5.5 wt.% sample content according to the below instructions

Equipment for RVA viscosity

[0075] This method is based on the Newport Scientific Method ST - 01. The RVA unit is turned on 30 minutes before use; checks should be made according to the instruction manual. An aluminum sample canister fitted with a polycarbonate paddle is used. A circulating water bath filled with demineralized water containing maximum 10% of antifreeze (e.g. ethylene glycol) is used and set to refrigerate to 10 °C. A laboratory balance having a precision of 0.01 g is used to weigh the materials.

Reagents for RVA viscosity

[0076] Standard laboratory demineralized water is used for viscosity measurements on neutral pH A buffer solution, pH 3.00 is used for viscosity measurements at pH 3. The buffer solution was prepared by adding 10 liters of demineralized water, 168.20 g citric acid monohydrate and 99.0 ml of 37% hydrochloric acid in a 20 liter container and mixing. Then, carefully adding 128.0 g of 50% sodium hydroxide and diluting to 20 liters with demineralized water and mixing. The pH should be between 2.95 - 3.05. If the pH is low add 1.0 N sodium hydroxide (NaOH) until the pH is in range. If the pH is high add 0.5 N HC1 until the pH is in range. Otherwise a commercial buffer solution comprising citric acid, sodium hydroxide and sodium chloride may be used. Procedure for RVA viscosity

[0077] First, the RV A instrument is operated with a paddle and zeroing the equipment at 160 rpm according to the instruction manual. Then, a standard calibration and adjustment procedure according to the instruction manual is carried out. The RVA is set as with a temperature of 50 °C and a speed of 960 rpm at the start (time 0).

[0078] The sample is prepared by weighing 1.65 gram of the sample into the canister, and then adding either water of buffer to solution to a total weight of 30.00 g ± 0.02 g. The paddle is placed into the canister and the blade is jogged vigorously up and down through the suspension. Then it is ensured that any remaining sample lumps adhering to the inside of the canister are pushed down into the water. Following, the canister with sample is inserted into the RVA, and the tower is depressed to initiate the test.

[0079] After 10 seconds the speed of the RVA is decreased to 160 rpm. After 30 seconds the temperature is increased to a value of 95 °C which value is reached after 3 minutes. The temperature of 95°C is held for 20 minutes (time 23 minutes) after which within 3 minutes the temperature is brought back to 50 °C (time 26 minutes) which temperature is held for another 9 minutes after which the test is stopped (time 35 minutes). The final viscosity is the viscosity at 35 minutes.

Determining MCR viscosity

[0080] The viscosity of a sample was measured on an Anthon Paar Rheoplus Modular Compact Rheometer (MCR) 51 device using a cylinder and measuring cup, type CC27. A flow curve was measured in duplicate (average used) with a logarithmic ramp up, shear rate from 1 to 200 1/s at a temperature of 60°C. A logarithmic profile of viscosity in function of shear rate is obtained. The value at a share rate of 1/s is discussed in the Examples below.

Determining colorimetric parameters

[0081] Colorimetric parameters of the samples were measured using a Konika Minolta colorimeter. The colorimeter was warmed up for 30 minutes prior to use, and calibrated with a standard white plate before taking readings. Dry' starch was added to the measuring cup until the bottom was completely covered. The measuring cup was placed on the instrument before colorimetric parameter measurements were taken.

Determining pH [0082] A pH meter was calibrated with pH 4 and pH 7 buffers. The pH was taken from samples comprising 5 g of the sample suspended in 20 g of deionized water. The probe was inserted into the slurry, and the pH recorded when a stable reading was achieved.

Testing taste and odor

[0083] All starches were evaluated for taste and odor blindly in an application matrix (e.g. yoghurt, bechamel, ketchup). For each taste test 4 or 5 people were asked to smell and taste the product prepared and provided comments on odor and taste. For the Bechamel samples, these were place, in closed cans, in a water bath of 60°C. Then the cans were opened and the upper skin, if present, was removed. The sample was gently stirred with a spoon and tasted. The starches in ketchup and yoghurt were tasted a few days after their production in the application matrix.

Examples 1-3 and comparative example 1

[0084] A waxy corn starch slurry was adjusted to an alkaline pH level with sodium carbonate, effective to maintain the pH at neutral or basic pH during the subsequent thermal inhibition step. The alkaline waxy corn slurry was dewatered and then dried. The pH of the alkaline dried waxy corn starch was 9.6. The dried alkaline waxy com starch was additionally dehydrated in a heated reactor at temperatures between 100 and 145°C to less than 1 wt.% moisture. The thermal inhibition reaction was conducted by heating to 160°C for a defined time (160-170 min) until the desired inhibition level was achieved. The desired inhibition level was checked by RVA viscosity analysis of samples taken during the inhibition step. When the desired inhibition level was achieved, the TI starch was cooled down to room temperature, reslurried in tap water, filtered and dried. Alternatively, the reslurrification, filtration and drying step can be replaced by washing once after the bleaching step.

[0085] The TI starch obtained has a colorimetric parameter b that is 6.4, a colorimetric parameter L that is 91.9; and a final viscosity measured using a Rapid Visco Analyser at neutral pH of 1104 cP.

[0086] Then, a slurry is formed using 500 grams (dry weight) of said TI starch with tap water to a dry solids content (%DS) of 35.46% and a Baume value of 20 Be by adding water and starch to a beaker while stirring with a Dispermat® stirrer for 10 minutes. [0087] The for examples according to the invention, KMnCL was added in an amount of 0.05 wt.% for Example 1, in an amount of 0.1 wt.% for Example 2, and in an amount of 0.2 wt.% for Example 2. Then, the pH slurry was adjusted to 4.0 using a IN HCL solution. The bleaching reaction was carried out for a duration of 30 minutes.

[0088] For the comparative examples sodium hypochlorite (NaOCl) was added in an amount of 9.86 grams, which gives 0.75 grams of active chlorine being 0.15%, when calculated on the 500 grams of TI starch. The pH after addition of NaOCl was 7.4. The bleaching reaction was carried out for a duration of 15 minutes, after which the pH was 6.9. [0089] For all examples, the slurry was then neutralized with a 20 wt.% bisulfite solution until a slight excess of SO2 was analyzed in the slurry by SO2 strips. The neutralization was carried out for 10 minutes.

[0090] For all examples, the slurry was then filtered on a Buchner filter using a Macherey -Nagel filter paper (retention capacity 4-12 pm) using vacuum, and the solids (starch cake) were washed by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried and then filtered again. Then the solids were washed again by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried. During this second re-slurrying step the pH of the slurry was adapted to 5.0 with a IN HCL solution. The solids are filtered again and after flash drying the TI bleached starch was obtained having a moisture content of 12 wt.%, which was subjected to milling using a Braun lab mill.

Color value

[0091] The values for color were tested and the results are shown in Table 1 below for the color values. In Table 1 the color values for the TI starch prior to the bleaching step are also provided. In addition, the increase in the L value towards a value of 100 for the examples and comparative example is provided compared to the TI starch prior to the bleaching step.

Table 1

[0092] From the above table it is clear that with the examples 1-3 the values of L greatly increases (by 4.3 to even 6.8 units) and that the value of b greatly decreases (by 3.3 to 4.4). Similar improvements are provided by the comparative example.

Viscosity value

[0093] The final viscosity was tested and the results are shown in Tables 2 and 3 below. The viscosity was measured using RVA at both a neutral pH (Table 2) and a pH 3.0 (Table 3).

Table 2

Table 3

[0094] The results from the test at neutral pH shows that the comparative example showed additional viscosity stabilization by 6.2%. The examples according to the present invention showed a de-inhibition of the viscosity that is limited to a maximum of 15.9%. The results from the test at pH 3.0 shows that the comparative example showed a small effect on the viscosity , being an increase of 1.8%. The examples according to the present invention showed a de-mhibition of the viscosity that is limited to a maximum of 22.1%.

Taste and odor

[0095] The comparative example showed an off-taste and off-odor of chlorine. This product is therefore unsuitable for use in food applications. All the examples of the invention showed no effect on the taste and odor compared to the TI starch prior to bleaching and are suitable for use in food applications.

[0096] This Example shows that with the present invention a good balance can be obtained between taste/odor, color and viscosity.

Examples 4 and 5 and comparative example 2

[0097] A waxy corn starch slurry was adjusted to an alkaline pH level with sodium carbonate, effective to maintain the pH at neutral or basic pH during the subsequent thermal inhibition step. The alkaline waxy corn slurry was dewatered and then dried. The pH of the alkaline dried waxy corn starch was 9.6. The dried alkaline waxy com starch was additionally dehydrated in a heated reactor at temperatures between 100 and 145°C to less than 1 wt.% moisture. The thermal inhibition reaction was conducted by heating to 165°C for a defined time (160-170 min) until the desired inhibition level was achieved. The desired inhibition level was checked by RVA viscosity analysis of samples taken during the inhibition step. When the desired inhibition level was achieved, the TI starch was cooled down to room temperature, reslurried in tap water, filtered and dried. Alternatively, the reslurrification, filtration and drying step can be replaced by washing once after the bleaching step.

[0098] The TI starch obtained has a colorimetric parameter b that is 8.8, a colorimetric parameter L that is 89.1, a final viscosity measured at neutral pH using a Rapid Visco Analyser of 860 cP, and a final viscosity measured at pH 3.0 using a Rapid Visco Analyser of 723 cP.

[0099] Then, a slurry is formed using 500 grams (dry weight) of said TI starch with tap water to a dry solids content (%DS) of 35.46% and a Baume value of 20 Be by adding water and starch to a beaker while stirring with a Dispermat® stirrer for 10 minutes.

[0100] For the examples according to the invention, KMnOr was added in an amount of 0.1 wt.% for Example 4, and in an amount of 0.2 wt.% for Example 5. Then, the pH slurry was adjusted to 4.0 using a IN HCL solution. The bleaching reaction was carried out for a duration of 30 minutes.

[0101] For comparative example 2 sodium hypochlorite (NaOCl) was added in an amount of 9.86 grams, which gives 0.75 grams of active chlorine being 0.15%, when calculated on the 500 grams of TI starch. The pH after addition of NaOCl was 6.6. The bleaching reaction was carried out for a duration of 15 minutes, after which the pH was 6.5. [0102] For all examples, the slurry was then neutralized with a 20 wt.% bisulfite solution until a slight excess of SO2 was analyzed in the slurry by SO2 strips. The neutralization was carried out for 10 minutes.

[0103] For all examples, the slurry was then filtered on a Buchner filter using a Macherey -Nagel filter paper (retention capacity 4-12 pm) using vacuum, and the solids (starch cake) were washed by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried and then filtered again. Then the solids were washed again by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried. During this second re-slurrying step the pH of the slurry was adapted to 5.0 with a IN HCL solution. The solids are filtered again and after flash drying the TI bleached starch was obtained having a moisture content of 12 wt.%, which was subjected to milling using a Braun lab mill.

Color value

[0104] The values for color were tested and the results are shown in Table 4 below for the color values. In Table 4 the color values for the TI starch prior to the bleaching step are also provided. In addition, the increase in the L value towards a value of 100 for the examples and comparative example is provided compared to the TI starch prior to the bleaching step.

Table 4

[0105] From the above table it is clear that with the Examples 4-5 the values of L greatly increases (by 5.9 to even 6.3 units) and that the value of b greatly decreases (by 3.8 to 4.5). Similar improvements are provided by the comparative example.

Viscosity value

[0106] The final viscosity was tested and the results are shown in Tables 5 and 6 below. The viscosity was measured using RVA at both a neutral pH (Table 5) and a pH 3.0 (Table 6).

Table 5 Table 6

[0107] The results from the test at neutral pH shows that the Examples according to the invention have only a small or no viscosity decrease. The results from the test at pH 3.0 shows that the examples according to the present invention showed a de-inhibition of the viscosity that is limited to a maximum of 8.9%.

Taste and odor

[0108] The comparative example showed an off-taste and off-odor of chlorine. This product is therefore unsuitable for use in food applications. All the examples of the invention showed no effect on the taste and odor compared to the TI starch prior to bleaching and are suitable for use in food applications.

Examples 6 and 7 and comparative example 3

[0109] A waxy tapioca starch slurry was adjusted to an alkaline pH level with sodium carbonate, effective to maintain the pH at neutral or basic pH during the subsequent thermal inhibition step. The alkaline waxy corn slurry was dewatered and then dried. The pH of the alkaline dried waxy tapioca starch was 9.7. The dried alkaline waxy tapioca starch was additionally dehydrated in a heated reactor at temperatures between 100 and 145°C to less than 1 wt.% moisture. The thermal inhibition reaction was conducted by heating to 155°C for a defined time (300 min) until the desired high inhibition level was achieved. The desired inhibition level was checked by RVA viscosity analysis of samples taken during the inhibition step. When the desired inhibition level was achieved, the TI starch was cooled down to room temperature, reslurried in tap water, filtered and dried. Alternatively, the reslurrification, filtration and drying step can be replaced by washing once after the bleaching step. [0110] The TI starch (non-bleached) obtained has a colorimetric parameter b that is 9.9, a colorimetric parameter L that is 87.3; and a final viscosity measured at neutral pH using a Rapid Visco Analyser of 334 cP.

[0111] Then, a slurry is formed using 500 grams (dry weight) of said TI starch with tap water to a dry solids content (%DS) of 35.01% and a Baume value of 20 Be by adding water and starch to a beaker while stirring with a Dispermat® stirrer for 10 minutes.

[0112] For the examples according to the invention, KMnOr was added in an amount of 0.1 wt.% for Example 6, and in an amount of 0.05 wt.% for Example 7. Then, the pH slurry was adjusted to 4.0 using a IN HCL solution. The bleaching reaction was carried out for a duration of 30 minutes.

[0113] For comparative example 3 sodium hypochlorite (NaOCl) was added in an amount of 6.46 grams, which gives 0.5 grams of active chlorine being 0.1%, when calculated on the 500 grams of TI starch). The pH after addition of NaOCl was 8.45. The bleaching reaction was carried out for a duration of 15 minutes, after which the pH was 7.95.

[0114] For all examples, the slurry was then neutralized with a 20 wt.% bisulfite solution until a slight excess of SO2 was analyzed in the slurry by SO2 strips. The neutralization was carried out for 10 minutes.

[0115] For all examples, the slurry was then filtered on a Buchner filter using a Macherey -Nagel filter paper (retention capacity 4-12 pm) using vacuum, and the solids (starch cake) were washed by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried and then filtered again. Then the solids were washed again by adding tap water in a ratio of 3 times water (by weight) to the weight of the solids obtained, re-slurried. During this second re-slurrying step the pH of the slurry was adapted to 5.0 with a IN HCL solution. The solids are filtered again and after flash drying the TI bleached starch was obtained having a moisture content of 12 wt.%, which was subjected to milling using a Braun lab mill.

Color value

[0116] The values for color were tested and the results are shown in Table 7 below for the color values. In Table 7 the color values for the TI starch prior to the bleaching step are also provided. In addition, the increase in the L value towards a value of 100 for the examples and comparative example is provided compared to the TI starch prior to the bleaching step. Table 7

[0117] All (comparative) examples of Table 7 were tested in yoghurt. The bleached examples provided a whiter color in yoghurt compared to the non-bleached TI starch.

[0118] From the above table it is clear that with the Examples 6 and 7 the values of L greatly increases (by 4.49 to even 6.04 units) and that the value of b greatly decreases (by 2.56 to 2.94). Similar improvements are provided by the comparative example.

Viscosity value

[0119] The final viscosity was tested and the results are shown in Tables 8 and 9 below. The viscosity was measured using RVA at both a neutral pH (Table 8) and a pH 3.0 (Table 9).

Table 8

Table 9

[0120] The results from the test at neutral pH shows that all example showed additional viscosity stabilization. The results from the test at pH 3.0 shows that the comparative example showed only a very slight increase on the viscosity. The examples according to the present invention showed hardly any de-inhibition of the viscosity; it is limited to a maximum of 4.0%.

Taste and odor

[0121] All (comparative) examples were tested for taste and odor in yoghurt. The comparative example showed a strong off-taste. This product is therefore unsuitable for use in food applications. All the examples of the invention were found to be very smooth and had a creamy mouthfeel, without any off-taste and are suitable for use in food applications.

Example 8 (Bechamel sauce)

[0122] To test if the TI bleached starches according to the present invention are suitable for food applications tests were carried out in a bechamel sauce (for application at more neutral pH level) and in ketchup (for application at more acidic pH level).

[0123] A Bechamel sauce was prepared by mixing either a TI bleached starch according to Example 4 or a TI starch prior to bleaching according to Example 4 (52.5 gram/4.2 wt.%), skimmed milk powder (112.5 gram/9.0 wt.%), salt (6.25 gram/0.5 wt.%), and sodium caseinate (6.25 gram/0.5 wt.%) with water (978.75 gram/78.3 wt.%) wherein the wt.% are based on the total weight of the Bechamel sauce. Next melted butter (93.75 gram/7.5 wt.%) was added and mixed. The mixture was heated to 95 °C for 20 minutes and the mixture was then poured in cans that were closed. After standing for one day the viscosity was measured.

[0124] It was noted that the MCR viscosity of the Bechamel sauce was 5086 cP for the non-bleached TI starch and it hardly deteriorated for the bleached TI starch (5206 cP). [0125] The L colorimetric value of the Bechamel sauce was 80.99 for the nonbleached TI starch and 83.44 for bleached TI starch, which clearly shows an improvement. The b colorimetric value of the Bechamel sauce was 20.37 for the non-bleached TI starch and 21.03 for the bleached TI starch, which is very similar. The closed cans were heated to 60 °C in a water bath, opened and stirred and the taste was evaluated which were found to have an off-taste for the non-bleached TI starch, tasting like cardboard, and a good taste, more milky for the bleached TI starch. This shows that the TI bleached starches according to the present invention are suitable for use in food applications at neutral pH.

Example 9 (ketchup)

[0126] To test if the TI bleached starches according to the present invention are suitable for food applications tests were carried out in a ketchup for acidic pH.

[0127] A ketchup was prepared by mixing the following dry ingredients, being a starch (2.2 wt.%), sugar (6 wt.%), salt (1 wt.%), and citric acid monohydrate (0.3 wt.%) and by separately mixing tomato concentrate (30 wt.%), vinegar (5 wt.%), and water (55.5 wt.%). The dry ingredients are added to the wet ingredients and mixed using a typhoon head IKA stirrer and heating to 95 °C and holding for 10 minutes. Then the mixture is poured into sample pots and cooled in a ice/water bath. The cans were closed and after standing for one day the viscosity was measured.

The following starches were tested:

• TI starch prior to bleaching, as discussed in Examples 4-5

• Starch according to Example 4

• Starch according to Comparative example 3

[0128] It was noted that the viscosity at shear rate 1/s was 15.667 cP for the nonbleached TI starch and it hardly deteriorated for the bleached TI starch according to Example 4 (14.453). The comparative example shows a similar viscosity (14.156 cP). The pH value of the non-bleached TI starch was 3.68 and that of the starch according to Example 4 and comparative example 2 was both 3.69. Table 10 below shows the color values; even though with the eye no direct difference between the samples was observed, the colorimetric data shows an improvement in color value with the bleached samples. Table 10.

[0129] Sensory tests with four people were carried out. The ketchup with the starch according to comparative example 2 was found to have a chemical, astringent, harsh sour and chlorine taste. The ketchup with the starch according to the present invention in example 4 was found to have a more sweet flavor than the sample with the non-bleached TI starch and was the preferred sample.

[0130] This shows that the TI bleached starches according to the present invention are suitable for use in food applications at acidic pH.