THERMALLY INHIBITED. OZONE TREATED STARCH OR FLOUR. AND A METHOD OF MANUFACTURING A THERMALLY INHIBITED. OZONE TREATED STARCH OR FLOUR

FIELD OF THE INVENTION

[0001] The present invention relates to a thermally inhibited, ozone treated starch or flour, and a method of manufacturing a thermally inhibited, ozone treated starch or flour. In particular, the present invention relates to a process for manufacturing a thermally inhibited, ozone treated starch or flour without modifying the functional properties of the initial thermally inhibited starch or flour. Thermally inhibited, ozone treated starch or flour is useful in industrial and food applications.

BACKGROUND OF THE INVENTION

[0002] Unmodified starch or flour can be heated in water to above the gelatinisation temperature in water to form a slurry. Upon exposing the slurry to heat, the starch or flour becomes hydrated. The starch or flour fraction gelatinises and swells resulting in the viscosity of the slurry increasing. In some fields, the increase in viscosity is useful. For example, in industrial and food applications. However, the hydrated and swollen starch or flour is structurally weak, and upon further heating or prolonged exposure to the same heat, the hydrated and swollen starch or flour breaks down and the viscosity of the slurry reduces. Furthermore, any exposure to shear, rapid movement, extreme pH or other harsh conditions also causes the hydrated and swollen starch or flour to break down resulting in a reduction in the viscosity of the slurry.

[0003] To restrict the over-swelling and to prevent the breakdown of the starch or flour, thermal inhibition of the starch or flour can be used. Thermal inhibition induces the interaction between molecules in the starch or flour, thereby allowing the resultant thermally inhibited starch or flour to be resistant to heat, shear or high/low pH conditions. Thermal inhibition allows the optimal swelling of the starch or flour to achieve the appropriate prolonged viscosity profile without over-swelling the starch or flour, which would lead to a breakdown in the viscosity profile.

[0004] Alternatively, crosslinks between starch or flour molecules can be introduced through contact with chemical reagents. Typically, consumers are looking for minimally processed foods with simplified and/or cleaner packaging labels. Although there is no regulated position for cleaner labels, perceptions and public opinion are increasingly pushing food processors and product developers to find and use food ingredients that are not modified or overly-processed. Thermal inhibition of starch or flour provides a way of forming a starch or flour that is resistant to over-swelling upon heating in water to above the gelatinisation temperature, but which does not contain additional chemicals. Consumers often prefer more natural treatments and starches or flours which are less chemically processed. Starches and flours have been developed which are thermally inhibited to enhance the functionality in terms of viscosity, stability to shear, acid and heat. These starches and flours do not use heavy chemicals or chemicals mentioned in the Code of Federal Regulations Title 21, Subpart 1 Multipurpose Additives, Section 172.892 Food Starch-Modified.

[0005] Thermal inhibition of starch or flour often comprises the steps of:

(1) dehydrating the starch or flour until it is anhydrous, or substantially anhydrous (i.e. having a moisture content of 1 weight % or less); and,

(2) heat treating the anhydrous, or substantially anhydrous starch or flour at a temperature and a period of time to result in inhibition. Typically, the temperature of the heat treatment is from 140 °C to 180 °C. Typically, the period of time for heat treatment is from 0.5 to 20 hours.

[0006] The resultant thermally inhibited starch or flour can be heated in water to above the gelatinisation temperature to form a slurry having a desired high viscosity, but without the susceptibility to break down upon exposure to heat. The resultant thermally inhibited starch or flour has the same (or similar) characteristics to a chemically crosslinked starch or flour, without the need to use chemical reagents.

EP2246365, EP0721471, EP1038882, EP0804488, EP0830379, EP1281721, EP2116137, EP2246365, EPl 102792 EP2153890, EP2420314, EP2060320, W02009/064722, EPl 159880, EP278358 and EP2674038 describe the thermal inhibition of starch or flour.

[0007] One drawback of thermal inhibition is the resultant colour of the starch or flour. Upon heat treating a dehydrated starch or flour, the starch or flour often changes colour and becomes yellow and/or tan. [0008] White, viscosity functionalised, starch or flour products can be produced by adding ester linkage forming chemicals such as citric acid or produced by adding citric acid and sodium carbonate to form a citric acid salt, followed by thermal treatment at a pH lower than 8. The ester linkage forming chemicals (such as citrate/citric acid or citric acid derivatives) are incorporated into the starch or flour in an aqueous slurry, the starch or flour is dried and then thermal treatment causes the crosslinking reaction to produce starch or flour esters. These starches or flours exhibit viscosity stability and white colour, but they have a negative aspect in that they are chemically crosslinked by the citrate/citric acid to form starch or flour esters which are typically considered as chemically modified.

[0009] Native starches or flours are not ideally suited for processed food formulations. Therefore, native starches or flours are functionalised by chemical modification. For chemically modified starches or flours, Code of Federal Regulations Title 21, Subpart 1 Multipurpose Additives, Section 172.892 Food Starch-Modified, requires that the packaging label bears the name of the additive (such as “Food Starch-Modified”). However, physically functionalised starches or flours do not require such labelling on ingredient declarations. [0010] It remains a goal of starch or flour developers to produce a white, viscosity functionalised starch or flour with a white colour free from chemical substituents, which can be labelled as unmodified starch or flour and has a more natural formation process, free from crosslinking chemicals.

[0011] Chlorine based bleaching agents have been used to decolourise starches and flours, but these leave residual chemicals, tastes and odours, and are classified as modified starches and flours according to regulatory agencies in many regions.

[0012] Peroxide and other oxidants have been used to decolourise starches and flours, but these are classified as modified starch and flours in many regions by regulatory agencies. [0013] There is an unmet need to form a white or near white, thermally inhibited starch or flour. In particular, there is an unmet need to form a white or near white, thermally inhibited starch or flour without chemical substituents such as starch esters or flour esters and to attain a final product which can be labelled as unmodified starch or unmodified flour.

SUMMARY OF THE INVENTION

[0014] The present invention relates to a thermally inhibited, ozone treated starch or flour, and a method of manufacturing a thermally inhibited, ozone treated starch or flour. In particular, the present invention relates to a process for manufacturing a thermally inhibited, ozone treated starch or flour without substantially modifying the functional properties of the initial thermally inhibited starch or flour. Thermally inhibited, ozone treated starch or flour is useful in industrial and food applications.

[0015] Consumers often want minimally processed foods with simplified/ cleaner packaging labels. Although there is no regulated position for cleaner packaging labels, perceptions and public opinion are increasingly pushing the food processors/product developers to use/find food ingredients that have not been “modified or processed”.

[0016] It is known that thermal inhibition can be used to make starches or flours with the same functional properties as chemically crosslinked starches or flours. These thermally inhibited starches and flours possess both process tolerances (such as resistance to heat, acid and shear) as well as improved texture and viscosity stability.

[0017] Thermal inhibition under alkaline conditions (also known as alkaline roasting) tans the starches and flours to a brown or amber colour, which impacts the colour of the finished food product. This is significantly disadvantaged with respect to consumer preference.

[0018] During the thermal inhibition process, polymerisation of dehydrated carbohydrates can create unsaturated species. Furthermore, some natural pigments or colour precursors in the starch or flour may undergo a chromophore shift in the alkaline environment which can be fixed at high temperature treatment. Thermal inhibition treatment can generate different colour species, and these cannot be easily removed by post washing, solvent treatment or other label friendly methods.

[0019] The present inventors surprisingly discovered that whitened, thermally inhibited starches and flours can be produced using ozone without substantially impacting the stability of the thermally inhibited starch or flour. Moreover, for certain processing conditions, the process of the invention may help reducing the microbial load of the manufactured products.

[0020] Representative features of the present invention are set out in the following clauses, which stand alone or may be combined, in any combination, with one or more features disclosed in the text and/or figures of the specification.

[0021] The present invention is as set out in the following clauses:

1. A thermally inhibited, ozone treated starch or flour, having the HunterLab colorimetric parameters of: plus 2 % or more (L);

0.15 % more or less (a) towards 0; and,

0.1 % more or less (b) towards 0; compared to the HunterLab colorimetric parameters of the thermally inhibited starch or flour prior to ozone treatment.

2. A thermally inhibited, ozone treated starch or flour, optionally the starch or flour of clause 1, having HunterLab colorimetric parameters of: from 90 to 100 (L); from -1.0 to + 1.0 (a); and, from 0 to + 7 (b); or, from 93 to 100 (L); from -0.3 to + 0.3 (a); and, from 0 to + 4.5 (b).

3. The starch or flour of clause 1 or clause 2, being free from ester crosslinks.

4. The starch or flour of any one of the preceding clauses, having a viscosity of plus or minus thirty cP percent, or plus or minus twenty cP percent, or plus or minus ten cP percent, or plus or minus five cP percent, or plus or minus two cP percent, or plus or minus one cP percent the viscosity of the thermally inhibited, ozone treated starch or flour prior to ozone treatment.

5. The starch or flour of any one of the preceding clauses, being any starch or flour derived from any native source, optionally from plants, optionally from cereals, tubers and roots, legumes and fruits, optionally from com, potato, sweet potato, barley, wheat, rice, sago, Kudzu, amaranth, tapioca (cassava), arrowroot, canna, pea, banana, quinoa, oat, rye, millet, triticale and sorghum, optionally, waxy, low amylose and high amylose varieties, optionally, waxy-sugary 2 com double mutant, low amylose sugary -2-com double mutant, highly phosphorylated potato, highly phosphorylated waxy potato, SSIII mutant potato, S Sill mutant waxy potato, SSIII and BE1 double mutant potato, SSIII, BEl.mutant waxy potato, or, short lived amylopectin waxy potato mutant. 6. A method of manufacturing a thermally inhibited, ozone treated starch or flour, comprising the steps of: providing a thermally inhibited starch or flour; subjecting the thermally inhibited starch or flour to an ozone treatment for a time sufficient to achieve a thermally inhibited, ozone treated starch or flour wherein the HunterLab colorimetric values have: increased by 2 % or more (L); decreased or increased by 0.15 % or less (a) towards 0; and, decreased or increased by 0.1 % or less (b) towards 0, wherein the L, a and b are HunterLab colorimetric parameters.

7. The method of clause 6, wherein the thermally inhibited starch or flour is subjected to the ozone treatment for a time sufficient to achieve a thermally inhibited, ozone treated starch or flour having HunterLab colorimetric parameters of: from 90 to 100 (L); from -1.0 to + 1.0 (a); and, from 0 to + 7 (b), or, from 93 to 100 (L); from - 0.3 to + 0.3 (a); and, from 0 to + 4.5 (b).

7 A. A method of manufacturing a thermally inhibited, ozone treated starch or flour, comprising the steps of: providing a thermally inhibited starch or flour; subjecting the thermally inhibited starch or flour to an ozone treatment for a time sufficient to achieve a thermally inhibited, ozone treated starch or flour having HunterLab colorimetric parameters of: from 90 to 100 (L); from -1.0 to + 1.0 (a); and, from 0 to + 7 (b), or, from 93 to 100 (L); from - 0.3 to + 0.3 (a); and, from 0 to + 4.5 (b).

8. The method of clause 6, clause 7 or clause 7A, wherein the viscosity of the thermally inhibited starch or flour changes by plus or minus thirty cP percent, or plus or minus twenty cP percent, or plus or minus ten cP percent, or plus or minus five cP percent, or plus or minus two cP percent, or plus or minus one cP percent upon ozone treatment.

9. The method of any one of clauses 6, 7, 7A or 8, wherein the ozone treatment includes exposing the thermally inhibited starch or flour to ozone at from 10 weight % in air or less, or, from 5 weight % in air or less, or, from 1 weight % in air or less, or, from 0.5 weight % in air or less, or, from 0.25 weight % in air or less; or, from 1 weight % or less in air or less (plus or minus 0.05 weight %).

10. The method of any one of clauses 6, 7, 7A, 8 or 9, wherein the ozone treatment includes exposing the thermally inhibited starch or flour to ozone for from 180 minutes or less, or, from 150 minutes or less, or, from 120 minutes or less, or, from 90 minutes or less, or, from 60 minutes or less, or, from 30 minutes or less, or, from 20 minutes or less, or, from 15 minutes or less, or, from 10 minutes or less, or, from 5 minutes or less (plus or minus 1 minute).

11. The method of any one of clauses 6, 7, 7A, 8, 9 or 10, wherein the ozone treatment is conducted at a pH of from 2 to 9, or, from 3 to 8.5, or from 4 to 7, or from 4.5 to 6.5 (plus or minus 0.5); and/or, wherein the ozone treatment is conducted at a temperature of from 40 °C or less, or, from 35 °C or less, or, from 30 °C or less, or, from 25 °C or less, or, from 20 °C or less, or, from 15 °C or less, or, from 10 °C or less (plus or minus 2 °C).

12. The method of any of clauses 6, 7, 7A, 8, 9, 10 or 11, further comprising the step of: forming a slurry comprising thermally inhibited starch or flour and water, wherein the slurry contains from 40 weight % of thermally inhibited starch or flour or less, or, from 35 weight % of thermally inhibited starch or flour or less, or, from 30 weight % of thermally inhibited starch or flour or less, or, from 25 weight % of thermally inhibited starch or flour or less, or, from 20 weight % of thermally inhibited starch or flour or less, or, from 15 weight % of thermally inhibited starch or flour or less, or, from 10 weight % of thermally inhibited starch or flour or less, or from 5 weight % of thermally inhibited starch or flour or less, or from 1 weight % of thermally inhibited starch or flour or less.

13. The method of any one of clauses 6 to 12, wherein the thermally inhibited, ozone treated starch or flour is as set out in any one of clauses 3 to 5.

14. A thermally inhibited ozone treated starch or flour obtained by, or obtainable by, the method of any one of clauses 6 to 13.

15. An industrial or food product comprising the thermally inhibited ozone treated starch or flour of any one of clauses 1 to 5, or 14.

DETAILED DESCRIPTION

[0022] Aspects of the present invention are described below with reference to the accompanying drawings. The accompanying drawings illustrate various aspects of systems, methods, and aspects of various other examples of the present invention. Any person with ordinary skill in the art will appreciate that the illustrated element boundaries (e.g. boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. It may be that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of one element may be implemented as an external component in another and vice versa. Furthermore, elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are described with reference to the following drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating principles.

[0023] Figure 1 shows a typical apparatus used to subject a thermally inhibited starch or flour to ozone treatment.

[0024] Figure 2 shows a viscosity profile of a thermally inhibited, ozone treated starch wherein the ozone treatment was performed under different pH conditions. [0025] Figure 3 shows a viscosity profile of a thermally inhibited, ozone treated starch wherein the ozone treatment was performed for different lengths of time.

[0026] Figure 4 shows a viscosity profile of a thermally inhibited, ozone treated starch wherein the ozone treatment was performed for different lengths of time.

[0027] Aspects of the present invention will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the several figures, and in which example aspects are shown. Aspects of the claims may, however, be embodied in many different forms and should not be construed as limited to the aspects set forth herein.

[0028] The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of aspects of the present invention, the preferred systems and methods are now described.

[0029] Some of the terms used to describe the present invention are set out below: [0030] “Crosslink” refers to a chemical structure that bridges two or more polysaccharide chains via covalent bonds. Typically, the polysaccharide chains form a starch or a flour. Most commonly used crosslinking reagents used to modify starches include, but are not limited to, POCh, STMP (sodium trimetaphosphate), mixtures of STMP and STPP (sodium tripolyphosphates), and adipic acetic mixed anhydride. One non limiting example of a chemical that can form crosslinks between two or more polysaccharide chains is citric acid. Another example of a chemical that can form crosslinks between two or more polysaccharide chains are acid anhydrides, including but not limited to succinic anhydride, maleic anhydride, glutaric anhydride and citric anhydride.

[0031] “HunterLab” refers to the colour space that is defined by the International Commission on Illumination which expresses colour as three numerical values: L (lightness); a (green-red colour components); and, b (blue-yellow components). The “L” value indicates light and dark colours, for example a low number (of from 0 to 50) indicates dark colours whilst a high number (of from 51 to 100) indicates light colours. The “a” value indicates red and green colours, where a positive value indicates red and a negative value indicates green. The “b” value indicates yellow and blue colours, where a positive number indicates a yellow colour and a negative number indicates a blue colour. All three colours are required to completely describe a colour.

[0032] “Mixture” refers to a substance formed by combining two or more different components together. The mixture may be uniform, or may not be uniform throughout.

[0033] "Ozone" refers to a strong oxidant. Temperature and pH has an important influence on the half-life of ozone. The solubility of ozone decreases at higher temperatures and is less stable. Ozone acts via an oxygen radical in neutral or acidic media, whereas in alkaline media the hydroxyl radical predominates. Each of these radicals may act through a different pathway, and so different reactions will result depending on the reaction conditions.

[0034] “Ozone treated starch or flour” refers to the oxidation by ozone of coloured (i.e. not white) compounds present in thermally inhibited starch or flour.

[0035] “Slurry” refers to a mixture of starch or flour in water formed by heating the starch or flour in water to above the gelatinisation temperature. Optionally, a slurry contains from 40 weight % of thermally inhibited starch or flour or less; or, from 35 weight % of thermally inhibited starch or flour or less; or, from 30 weight % of thermally inhibited starch or flour or less; or, from 25 weight % of thermally inhibited starch or flour or less; or, from 20 weight % of thermally inhibited starch or flour or less; or, from 15 weight % of thermally inhibited starch or flour or less; or, from 10 weight % of thermally inhibited starch or flour or less; or from 5 weight % of thermally inhibited starch or flour or less; or, from 1 weight % of thermally inhibited starch or flour or less.

[0036] “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. Amylopectin is a branched macromolecule composed of a-(l ,4) linked glucan chains with a-(l ,6) glucosidic branch points. Amylose is a relatively long, linear glucan chain containing a-(l ,4) linkages (99%) and a few branches of a-(l ,6) type. Regular starches consist of from 15 to 30 weight % amylose and from 70 to 85 weight % amylopectin. However, amylose-free waxy starches contain essentially 100 weight % amylopectin, and high-amylose starches consist of greater than 40 weight % amylose content. The birefringence pattern and Maltese cross of starch granules revealed under polarized light microscopy is attributable to their semicrystalline nature. Starches typically have a natural pH of about 5.0 to about 6.0.

[0037] “Starch granules” are generally insoluble in cold water, but when heated in excess water, they absorb water, swell and eventually lose their crystalline order and therefore their birefringence. This irreversible phase transition is called gelatinization. [0038] Granule swelling, gelatinization and starch composition mainly contributes to the viscosifying property of starches.

[0039] “Thermal inhibition” refers to a process that heats non-gelatinised, dehydrated starch or flour having an alkaline pH (i.e. the pH is greater than 7.5) in a manner that inhibits the starch or flour.

[0040] “Thermally inhibited starch or flour” refers to a starch or flour that has undergone alkaline treatment followed by heat treatment at high temperature (from 140 °C to 180 °C, preferably from 150 °C to 170 °C) in a dehydrated state (i.e. a moisture content of less than 1 weight %) to form a starch or flour that is functionally similar to native starch or flour but which has a high tolerance to processing variables such as heat, shear and pH extremes. In one non limiting example of forming a thermally inhibited starch of flour, a starch or flour and water slurry is prepared, wherein the starch or flour comprises about from 30 to 40 weight % of the slurry, the balance being water. Alternatively, the starch or flour may comprise a higher content of the slurry, for example greater than 60 weight%. 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 or flour anhydrous or substantially anhydrous, and preferably having a content of less than 0.5 weight % moisture. Next, the starch or flour 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 in some aspects from 1 to 20 hours, to achieve thermal inhibition. [0041] “Weight %” refers to the percentage weight in grams of a component of a composition in every 100 grams of a composition. For example, if a composition contains 10 weight % of component A, then there is 10g of component A for every 100g of the composition.

[0042] “White” refers to a starch of flour that has the HunterLab colorimetric values of L = 100, a = 0 and b = 0. The term “near white” refers to a starch or flour that has HunterLab colorimetric values close to these values (i.e. from 90 to 100 (L); from -1.0 to + 1.0 (a); and, from 0 to + 7 (b)).

[0043] The present invention relates to a thermally inhibited, ozone treated starch or flour. The thermally inhibited, ozone treated starch or flour originates from native starch or flour.

[0044] Optionally, the thermally inhibited, ozone treated product is derived from starch. The starch may be any starch derived from any native source. A native starch as used herein, is one as it is found in nature. Starches derived from nature, for example from plants, are also suitable. Typical sources for these starches are cereals, tubers and roots, legumes (including pea, chick pea, lentils, fava beans, lupin bean, and mung bean) and fruits. The native source can be any variety, including without limitation, com, potato, sweet potato, barley, wheat, rice, sago, Kudzu, amaranth, tapioca (cassava), arrowroot, canna, pea, banana, quinoa, oat, rye, millet, triticale and sorghum, as well as low amylose (waxy) and high amylose varieties thereof. “Low amylose or waxy varieties” 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 may be physically treated by any method known in the art to alter the starch structure, such as by shearing or by changing the granular or crystalline nature of the starch, and as used herein is intended to include conversion and pregelatinisation. Methods of physical treatment known in the art include heat moisture treatment, annealing, high pressure treatment, jet-milling, micronization, ball-milling, homogenization, high shear blending, high shear cooking such as jet cooking or in a homogenizer, drum drying, spray-drying, spray cooking, chilsonation, roll-milling and extrusion, and thermal treatments of low (e.g. at most 2 weight %) and high (above 2 weight %) moisture containing starch. The starch may be also chemically modified by treatment with any reagent or combination of reagents known in the art.

[0045] Optionally, the thermally inhibited, ozone treated product is derived from flour. The flour may be any flour derived from any native source. A native flour as used herein, is one as it is found in nature. Flour derived from nature, for example from plants, are also suitable. Typical sources for these flours are cereals, tubers and roots as well as legumes (including pea, chick pea, lentils, fava beans, lupin bean, and mung bean). The native source can be any variety, including without limitation, com, potato, sweet potato, barley, wheat, rice, sago, Kudzu, amaranth, tapioca (cassava), arrowroot, canna, pea, banana, quinoa, oat, rye, millet, triticale and sorghum, as well as low amylose (waxy) and high amylose varieties thereof. “Low amylose or waxy varieties” is intended to mean a flour containing: at most 10% amylose by weight; optionally, at most 5%; optionally, at most 2%; optionally, at most 1% amylose by weight, of the flour. Amylose-free waxy starches contain essentially 100 % by weight amylopectin. “High amylose varieties” is intended to mean a flour 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 flour. Flours can also be produced through the recombination of mill streams at a milling site (to form recombined flour), or produced away from a milling site by reuniting milling fractions (to form reconstituted flour). The flour may be physically treated by any method known in the art to alter the flour structure, such as by shearing or by changing the granular or crystalline nature of the flour, and as used herein is intended to include conversion and pregelatinisation. Methods of physical treatment known in the art include heat moisture treatment, annealing, high pressure treatment, jet-milling, micronization, ball-milling, homogenization, high shear blending, high shear cooking such as jet cooking or in a homogenizer, drum drying, spray-drying, spray cooking, chilsonation, roll-milling and extrusion, and thermal treatments of low (e.g. at most 2 weight %) and high (above 2 weight %) moisture containing flour. The flour may be also chemically modified by treatment with any reagent or combination of reagents known in the art.

[0046] In some aspects, starch or flour can be derived from com mutants, waxy com mutants or low amylose (less than 10 % by weight amylose), sugary-2 double mutant or waxy sugary-2 double mutants.

[0047] In some aspects, starch or flour can be derived from highly phosphorylated (greater than 800 ppm phosphoms content) potato or highly phosphorylated (greater than 800 ppm phosphorus content) waxy potato, or SSIII mutant potato, or SSIII mutant waxy potato, or SSIII and BE1 double mutant potato, or SSIII, BE1 mutant waxy potato, or short chain amylopectin waxy potato mutant (lack of or non-functional GBSS1 combine with deficient or non-functional SSII and/or SSIII enzymes) or arrow root powder.

[0048] Optionally, the thermally inhibited, ozone treated product is derived from a mixture of starch and flour. Optionally, the ratio of starch to flour (starch: flour; in weight %) is from 1:9, or, from 2:8, or from 3:7, or, from 4:6, or, 5:5, or, from 6:4, or, from 7:3, or, from 8:2, or, from 9:1. Mixing the starch and flour can be effected with any known means in the art, examples thereof including without limitation a malaxer, a transport screw, an air-stream agitation mixer, a paddle mixer, a Z-mixer, a tumble mixer, a high speed paddle mixer, a power blender and the like.

[0049] In an alternative aspect, the thermally inhibited, ozone treated starch or flour is not limited to starch or flour, and can be derived from any saccharide. Optionally, the saccharide is a saccharide as found in nature. Saccharides derived from nature, for example from plants, are also suitable. Examples of saccharides include oligosaccharides, polysaccharides and/or a combination thereof. Polysaccharides have the general formula (CeHioOsjn with n being optionally between 2 and 40; optionally, between 2 and 30; optionally, between 2 and 20. Examples of polysaccharides include, without being limited thereto, cellulose, xyloglucan, galactoxyloglucan, beta glucan, glycogen, galactogen, inulin, arabinoxylans, pectins, other carboxylated polymers, chitin, peptidoglygans, dextrins such as maltodextrin, cyclodextrin and amylodextrin. The polysaccharide may be a single polysaccharide or a mixture of two or more polysaccharides.

[0050] The starch or flour from which the thermally inhibited, ozone treated starch or flour is derived, is thermally inhibited prior to ozone treatment to form a thermally inhibited starch or flour. Thermal inhibition can be effected with any known means in the art. Typically, thermal inhibition includes the steps of dehydrating a starch or flour, alkaline treating a starch or flour, and then heat treatment at high temperature (140 to 180 °C) in a dehydrated state (i.e. a moisture content of less than 1 weight %) to form a starch or flour that is functionally similar to the pre-treated starch or flour but which has a high tolerance to processing variables such as heat, shear and pH extremes.

[0051] Dehydration forms an anhydrous, or mostly anhydrous, starch or flour. In one non-limiting example of dehydrating the starch or flour, the starch or flour is suspended in water to form a slurry. Preferably, the slurry comprises the starch or flour at from 30 to 40 weight %. Alternatively, the starch or flour may be present at a higher content (for example from 60 weight % or greater), or the starch or flour may be present at a lower content (for example from 25 weight % or lower). The pH of the slurry is adjusted to from 8 to 11 using an alkaline source such as sodium carbonate. The slurry is then dewatered and dried. The dewatered starch or flour is dehydrated at a temperature of from 100 °C to 155 °C, and for a time period sufficient to render the starch or flour anhydrous or mostly anhydrous. The mostly anhydrous starch or flour has a moisture content of: 5 weight % or less; optionally, a moisture content of 2 weight % or less; optionally, a moisture content of 1 weight % or less. Typically, dehydration of the starch or flour is completed by heat treatment. However, dehydration of the starch or flour 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. Dehydration can be conducted at high pressure.

[0052] Alkaline treatment provides an alkaline, dehydrated starch or flour. Alkaline treatment is completed by any known method in the art. Examples of alkaline treatment include heating the starch or flour in water to above the gelatinisation temperature to form a slurry, and adjusting the pH of the slurry to a pH of from 8 to 11 using any known alkaline source including but not limited to sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), sodium carbonate (Na2COs) and/or potassium carbonate (K2CO3).

[0053] Thermal inhibition can be effected with any known means in the art. Typical thermal inhibition requires heat treatment. Typically, the heat treatment is conducted at a temperature of: from 140 °C to 180 °C; or, from 150 °C to 170 °C. Typically, heat treatment is conducted for: from 0.5 to 20 hours; or, from 1 to 20 hours. Other methods of thermal inhibition include the use of a fluidised bed reactor, a paddle mixer, Dextrinizer, vibrating spiral conveyor, microwave and radiofrequency technologies.

[0054] The degree to which a starch or flour is thermal inhibited can be altered by varying the conditions of the thermal inhibition. The resultant starch or flour is typically known as a low, medium or high thermally inhibited starch or flour. 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 or flour is thermally inhibited, rate of air flow, air to mass ratio, 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.

[0055] A thermally inhibited starch or flour is subjected to ozone treatment to form a thermally inhibited, ozone treated starch or flour.

[0056] Typically, ozone treatment uses an ozone generation system that can be turned on and tuned to output a desired concentration of ozone. Typically, the ozone generation system is tuned to generate an air flow containing 10 weight % ozone (plus or minus 5 weight %) when flowing at 1 LPM (litre per minute) (plus or minus 0.2 LPM). A second stream of air (typically compressed air) is mixed with the air flow containing the ozone to form a resultant mixed air flow containing 0.5 weight % ozone (plus or minus 0.1 weight %) when flowing at 26 LPM (plus or minus 5 LPM. The mixed air flow is directed into a tank for contact with the thermally inhibited starch or flour. Alternatively, the flow rate of the air flow containing ozone can be adjusted according to need. Further alternatively, the air flow containing the ozone is directed into a tank for contact with the thermally inhibited starch or flour without mixing with the second air flow.

[0057] Typically, a thermally inhibited starch or flour is subjected to ozone treatment in the form of a slurry. Typically, the slurry comprises the thermally inhibited starch or flour and water. [0058] Figure 1 shows a typical system 100 used to subject a thermally inhibited starch or flour to ozone treatment.

[0059] Compressed air 101 enters system 100. Typically, compressed air 101 contains oxygen at 21 weight % (plus or minus 5 weight %). The compressed air 101 passes through a needle valve 102 which regulates the rate at which the compressed air 101 flows through the system 100. The flow of the compressed air 101 passing through the system is monitored with a flow metre 103. Typically, compressed air 101 passes through system 100 at a flow rate of 25 litres per minute (plus or minus 5 litres per minute). The compressed air 101 then passes through a check valve 104. The check valve 104 allows the compressed air 101 to pass through in one direction only, thus preventing back flow. The compressed air 101 then passes into a tank 112.

[0060] Further compressed air 105 enters system 100. Typically, compressed air 105 contains oxygen at 21 weight % (plus or minus 5 weight %). The compressed air 105 passes through an oxygen concentrator 106. The oxygen concentrator 106 purifies the compressed air 105, thus concentrating the oxygen present in the compressed air 105.

[0061] Ozone is produced by any means known in the art. As shown in Figure 1, one way to generate ozone from air is to use an ozone generator 107. As shown in Figure 1, the compressed air 105 then passes through an ozone generator 107. The ozone generator 107 converts oxygen present in the compressed air 105 to ozone. Typically, ozonated compressed air 105 contains 90 weight % oxygen (plus or minus 5 weight %) and 10 weight % ozone (plus or minus 5 weight %). The ozonated compressed air 105 then passes through a needle valve 108, which regulates the rate at which the ozonated compressed air 105 flows through the system 100. The flow of the ozonated compressed air 105 passing through the system is monitored with a flow metre 109. Typically, the ozonated compressed air 105 passes through system 100 at a flow rate of 1 litre per minute (plus or minus 0.2 litres per minute). The ozonated compressed air 105 then passes through a check valve 110. The check valve 110 allows the ozonated compressed air 105 to pass through in one direction only, thus preventing back flow. The ozonated compressed air 105 then passes into the tank 112 through a bubbler 111. Typically, the bubbler 111 is placed at the bottom of the tank 112 to permit upward flow of the gas. Alternatively, the bubbler 111 can be placed at the middle or top of the tank 112. [0062] The thermally inhibited starch or flour to be ozone treated is placed in the tank 112 in a slurry. The thermally inhibited starch or flour is then exposed to ozone, for the ozone treatment, by bubbling ozone containing gas through the bubbler 111. [0063] To form the preferred concentration of ozone for the ozone treatment, the compressed air 101 and the ozonated compressed air 105 are combined in the tank 112. [0064] Optionally, the ozone treatment includes exposing the thermally inhibited starch or flour to ozone at a concentration of 10 weight % in air or less; or, 5 weight % in air or less; or, 1 weight % in air or less; or, 0.5 weight % in air or less; or, 0.25 weight % in air or less; or, 0.1 weight % in air or less (plus or minus 0.05 weight %).

[0065] Optionally, the ozone treatment includes exposing the thermally inhibited starch or flour to compressed air containing: 35 weight % oxygen or less; or, 30 weight % oxygen or less; or, 25 weight % oxygen or less; or, 20 weight % oxygen or less; or 15 weight % oxygen or less.

[0066] Optionally, the ozone treatment includes exposing the thermally inhibited starch or flour to compressed air containing 24 weight % oxygen and 0.5 weight % ozone. [0067] Optionally, the ozone treatment includes exposing the thermally inhibited starch or flour to ozone for: 180 minutes or less; or, 150 minutes or less; or, 120 minutes or less; or, 90 minutes or less; or, 60 minutes or less; or, 30 minutes or less; or, 20 minutes or less; or, 15 minutes or less; or, 10 minutes or less; or, 5 minutes or less (plus or minus 1 minute).

[0068] Optionally, the ozone treatment is conducted at a temperature of: 40 °C or less; or, 35 °C or less; or, 30 °C or less; or, 25 °C or less; or, 20 °C or less; or, 15 °C or less; or, 10 °C or less (plus or minus 2 °C).

[0069] Optionally, the thermally inhibited, ozone treated starch or flour is heated in water to above the gelatinisation temperature to form a slurry, wherein the slurry contains: 40 weight % or less of thermally inhibited starch or flour; or, 35 weight % or less of thermally inhibited starch or flour; or, 30 weight % or less of thermally inhibited starch or flour; or, 25 weight % or less of thermally inhibited starch or flour; or, 20 weight % or less of thermally inhibited starch or flour; or, 15 weight % or less of thermally inhibited starch or flour; or, 10 weight % or less of thermally inhibited starch or flour; or, 5 weight % or less of thermally inhibited starch or flour; or, 1 weight % or less of thermally inhibited starch or flour.

[0070] Optionally, the pH of the slurry is controlled. Hydrochloric acid (HC1) can be used to make the pH more acidic. Sodium hydroxide (NaOH) can be used to make the pH more basic. Optionally, the ozone treatment is conducted at a pH of: from 2 to 9; or, from 3 to 8; or, from 4 to 7; or, from 4.5 to 6.5 (plus or minus 0.5).

[0071] The thermally inhibited starch or flour is subjected to the ozone treatment to achieve a thermally inhibited, ozone treated starch or flour having from 90 to 100 (L); from - 1.0 to + 1.0 (a); and, from 0 to + 7 (b), wherein the L, a and b are HunterLab colorimetric parameters. Optionally, the thermally inhibited, ozone treated starch or flour is subjected to an ozone treatment to achieve a thermally inhibited, ozone treated starch or flour having from 93 to 100 (L); from - 0.3 to + 0.3 (a); and, from 0 to + 4.5 (b), wherein the L, a and b are HunterLab colorimetric parameters. The HunterLab colorimetric parameters are measured on a HunterLab colorimeter using a D65 illuminant and 10° reference angle.

[0072] Once ozone treatment is complete, the air in the tank moves from the tank 112 to a destruct unit 113 which removes any ozone present in the air. The de-ozonated air is then released to the atmosphere via vent 114.

[0073] After ozone treatment, the thermally inhibited, ozone treated starch or flour may be subjected to additional washing, drying and/or grinding steps.

[0074] A non-limiting example of a post ozone treatment includes washing and drying the thermally inhibited, ozone treated starch of flour. The method includes stirring the slurry by using a stir plate for 15 minutes, and then recording the pH of the thermally inhibited, ozone treated starch or flour as a slurry. The slurry is dewatered in a Buchner funnel using Whatman#4 filter paper, and tap water (350 ml) is poured through the cake in the top of the Buchner funnel. The cake is suspended in water to form a second slurry, and the initial pH of the second slurry is recorded. The pH of the second slurry is adjusted to pH 5 using 5 weight % HC1. The second slurry is stirred using a stir plate for 15 minutes. The second slurry is then dewatered in a Buchner funnel using Whatman#4 filter paper, and the cake from the top of the Buchner funnel is crumbled into an aluminium pan and exposed to 30 °C heat to dry until 10 weigh % moisture content is achieved. The dried thermally inhibited, ozone treated starch or flour is then grounded in a coffee grinder for 30 seconds, and sifted through a No. 7 screen.

[0075] Advantageously, the thermally inhibited, ozone treated starch or flour is whiter than thermally inhibited, non-ozone treated starch or flour.

[0076] Advantageously, the present invention discloses a white or near white, thermally inhibited starch (or flour) and a method of forming a white or near white thermally inhibited starch (or flour).

[0077] Once ozone treatment is complete, the slurry containing the thermally inhibited, ozone treated starch or flour is removed from the tank 112. To remove the water from the slurry, the slurry is placed in a Buchner funnel using Whatman#4 filter paper. An additional 350 ml of tap water is poured through the cake present in the top of the Buchner funnel before it cracks. [0078] The viscosity of the slurry containing the thermally inhibited, ozone treated starch or flour can be measured using a viscometer. Optionally, the viscosity of the slurry is the same as a slurry made in exactly the same way, but using the equivalent thermally inhibited (non-ozone treated) starch or flour. Optionally, the thermally inhibited, ozone treated starch or flour has a viscosity which is the same as the thermally inhibited, ozone treated starch or flour prior to ozone treatment. Optionally, the thermally inhibited, ozone treated starch or flour has a viscosity of: plus or minus thirty cP percent; or, plus or minus twenty cP percent; or, plus or minus ten cP percent; or, plus or minus five cP percent; or, plus or minus two cP percent; or, plus or minus one cP percent, of the viscosity of the thermally inhibited, ozone treated starch or flour prior to ozone treatment. The viscosity is measured using a viscometer

[0079] A Rapid Visco Analyser (RVA) PerkinElmer™ 4800 can be used to measure the viscosity profiles of ozone treated starches and flours, as well as control starches and flours. In one non-limiting example of taking a viscosity measurement, the samples are suspended in deionized (DI) water or in pH 3 buffer at 5.5 weight % dry starch or flour content (moisture corrected), approximately 1.8 g starch or flour is added to 28.2 g water/buffer; wherein the total suspension weighs 30.0 g. The RVA holds the mixture at 95 °C for 20 minutes at a constant 160 RPM. As used herein, the final viscosity of the composition or sample refers to the viscosity at the end of an RVA run.

[0080] Optionally, the thermally inhibited, ozone treated starch or flour may contain other components such as catalysts, inhibitors, anti-oxidants and starch or flour stabilising agents such as sodium sulphate.

[0081] Optionally, the thermally inhibited, ozone treated starch or flour is in solid form; optionally, as a powder. Optionally, the starch has an average particle size (“APS”) of from 1 to 100 pm; optionally the flour has an APS of from 100 to 500 pm. The APS can be determined by ASTM Cl 36-06.

[0082] Optionally, the thermally inhibited, ozone treated starch or flour is free from ester crosslinks. In chemically modified starches or flour, the ester crosslinks may be positioned between two or more starch or flour molecules, thereby forming a bridge. Optionally, the thermally inhibited, ozone treated starch or flour is free from such bridges. Optionally, the thermally inhibited, ozone treated starch or flour contains: less than 5 weight % ester crosslinks; or, less than 2.5 weight ester crosslinks; or, less than 1 weight % ester crosslinks; or, less than 0.5 weight % ester crosslinks; or, less than 0.1 weight % ester crosslinks (plus or minus 0.05 weight %). Examples of ester crosslinks are those having a general formula RCO2R’ (where R and R’ indicate attachment points on respective polysaccharide chains), such as citric acid cross links.

[0083] Advantageously, the present invention discloses a white or near white, thermally inhibited starch or flour, and a method of forming a white or near white thermally inhibited starch or flour, wherein the thermally inhibited starch or flour is free of ester crosslinks and the method does not require the use of chemical reagents.

[0084] Advantageously, the thermally inhibited, ozone treated starch or flour can be used in industrial or food products. Examples of industrial products include pharmaceutical, personal care and laundry of detergent products. Examples of food products include luxury drinks, such as coffee, black tea, powdered green tea, cocoa, adzuki-bean soup, juice, soyabeanjuice, 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 fibre-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. EXAMPLES

[0085] The following are non-limiting examples that discuss, with reference to tables and figures, some of the advantages of the present invention. The examples set forth herein are non-limiting examples and are merely examples among other possibilities.

Experimental techniques

[0086] The following section outlines the starting materials and experimental techniques used in the examples.

Starting materials

[0087] The following materials were used as starting materials:

Sample 1: a medium thermally inhibited waxy com starch.

Sample 2: a high thermally inhibited waxy com starch.

Sample 3: a medium thermally inhibited, post-washed com sample.

Sample 1 is made by the following procedure:

(1) A waxy maize alkaline base is made on the plant scale by adding soda ash to starch slurry (32 weight % dry starch) in an agitated tank. The pH of the sample was raised through forming a slurry by adding the flour or water at 30-35 weight % to water, and then adding soda ash until the desired pH was reached. Components of the slurry include dry basis waxy com starch, water, 35 weight % peroxide and soda ash.

(2) The pH of the slurry is adjusted until the pH falls in the range of from 9.3 to 9.5.

(3) The alkaline slurry is dewatered and flash dried. (4) Thermal inhibition occurs in a pilot Littleford Reactor that is steam jacketed, allowing the starch to be heated and agitated with paddles and constant supplemental heated air.

(5) The waxy maize alkaline base is added to the reactor. For the batch used to make sample 1, the alkaline base had a pH of 9.65, a moisture content of 8 weight %.

(6) The starch is heated at 121 °C (250 °F) to dehydrate the starch. The starch is heated for 75 minutes until the moisture is below 2 weight %.

(7) The starch temperature is increased to 154 °C (310°F) for 60 minutes to dehydrate the starch to less than 1 weight % moisture.

(8) The starch temperature is maintained at 154 °C (310°F) during thermal inhibition for an additional 270 minutes.

(9) The time at which a reaction is stopped is determined by periodically taking samples from the reactor for an RVA viscosity measurement (method outlined below). The target top viscosity is from 125 to 325 cP and the target final viscosity is from 300 to 500 cP. The steam to the reactor is released to stop heating the starch and to halt the reaction.

Sample 2 is made by the following procedure:

(1) A waxy maize alkaline base is made on the plant scale by adding soda ash to starch slurry (32 weight % dry starch) in an agitated tank. The pH of the sample was raised through forming a slurry by adding the flour or water at 30-35 weight % to water, and then adding soda ash until the desired pH was reached. Components of the slurry include dry basis waxy com starch, water, 35 weight % peroxide and soda ash.

(2) The pH of the slurry is adjusted until the pH falls in the range of from 9.3 to 9.5.

(3) The alkaline slurry is dewatered and flash dried. The final alkaline base has a moisture content of 5 weight % and a pH of from 9.7 to 9.9. (4) Thermal inhibition occurs in a plant Dextrinizer that is steam jacketed, with paddle agitators and controlled sweep air.

(5) The sample is heated at 121 °C (250 °F) for 100 minutes to dehydrate to a moisture content of 2 weight %. The alkaline base has from 5.57 to 6.44 weight % moisture and the pH ranges from 9.53 to 9.82.

(6) The starch temperature is increased to 154 °C (310°F) for approximately 80 minutes to dehydrate the starch to less than 1 weight % moisture.

(7) The starch temperature is maintained at 154 °C (310°F) during thermal inhibition reaction for an additional 290 minutes.

(8) The time at which a reaction is stopped is determined by periodically taking samples from the reactor for an RVA viscosity measurement (method outlined below). The target top viscosity is from 125 to 325 cP and the target final viscosity is from 300 to 500 cP. The reaction is stopped by dropping the starch into a cooler that agitates the dry thermally inhibited starch to decrease temperature. The product is then sifted before being packaged.

Sample 3 is made by the following procedure:

(1) Providing an unwashed, intermediate inhibited waxy com starch. The unwashed, intermediate inhibited waxy com starch has a moisture content of 0.76 weight %, and a HunterLab colorimetric value of 10.94 (b value).

(2) The Baume of the slurry is adjusted from 18.5 to 14.5.

(3) The pH is adjusted to 4.1 using sulfuric acid.

(4) The slurry is run through the dewatering system (using a Pneumapress) and drying system (using a flash dryer). [0088] Unless otherwise specified, each sample was thermally inhibited using a paddle reactor or Dextrinizer.

[0089] Each sample was heated in water to form a slurry. The resultant slurry contained from 30 to 40 weight % thermally inhibited starch or flour. The pH of the slurry was adjusted through addition of sodium carbonate to reach a pH of between 9 and 10.

[0090] The slurry was heat treated by adjusting the temperature of the slurry from ambient to 120 °C, and then heated to until the slurry became anhydrous. The slurry was thermally inhibited by further heating at from 155 to 165 °C for from 3 to 6 hours to obtain samples with the desired level if inhibition.

[0091] The moisture level of the thermally inhibited samples was less than 1 weight % water.

[0092] After, thermal inhibition sample 3 was re-slurried in water, then dewatered on a Pneumapress and flash dried.

Ozone Treatment

[0093] Unless otherwise specified, each sample was subjected to ozone treatment using the following procedure:

[0094] The ozone treatment used an ozone generation system that could be turned on and tuned to output a desired concentration of ozone. The ozone generation system was tuned to generate an air flow containing 10 weight % ozone when flowing at 1 LPM (litre per minute). Another stream of air (typically compressed air) was mixed with the air flow containing the ozone to form a resultant air flow containing 0.5 weight % ozone when flowing at 26 LPM.

[0095] A container of the thermally inhibited slurry was warmed to 25 °C and exposed to the air flow containing 0.5 weight % ozone when flowing at 26 LPM.

[0096] After exposure to ozone, the sample was then washed. The washing steps follow the procedure including the steps of: firstly the thermally inhibited, ozone treated starch as a slurry is stirred using a stir plate for 15 minutes, and then the pH of the thermally inhibited, ozone treated starch as a slurry is recorded. The slurry is dewatered in a Buchner funnel using Whatman#4 filter paper, and tap water (350 ml) is poured through the cake in the top of the Buchner funnel. The cake is suspended in water to form a second slurry, and the initial pH of the second slurry is recorded. The pH of the second slurry is adjusted to pH 5 using 5 weight % HC1. The second slurry is stirred using a stir plate for 15 minutes. The second slurry is then dewatered in a Buchner funnel using Whatman#4 filter paper, and the cake from the top of the Buchner funnel is crumbled into an aluminium pan and exposed to 30 °C heat to dry until 10 weigh % moisture content is achieved. The dried thermally inhibited, ozone treated starch or flour is then grounded in a coffee grinder for 30 seconds, and sifted through a No. 7 screen.

Determining moisture content

[0097] The moisture content of a sample was measured using a Mettler Toledo Halogen Moisture Analyser. A small amount of the sample (0.5 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 viscosity

[0098] The viscosity of a sample was measured using a Rapid Visco Analyser (RVA) Perkins Elmer 4800. A neutral and acidic measurement was taken for each sample. Each sample was suspended in deionised water at 5.5 weight % sample content, which corresponds to approximately 1.8 g of sample in 28.2 g of water. The total suspensions weighed 30.0 g. Each sample was then heated to 95 °C, and held at this temperature for 20 minutes at a constant 160 RPM.

Determining colorimetric parameters

[0099] Colorimetric parameters of the thermally inhibited, ozone treated samples were measured using a HunterLab colorimeter (HunterLab, LabScan XE). Illuminant D65 was used with a 0.5 inch aperture and a 10° reference angle. The colorimeter was warmed up for 30 minutes prior to use, and calibrated with standard white and black plates 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 and covered with the light blocking cup before colorimetric parameter measurements were taken.

Determining pH [0100] 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.

Control samples

[0101] Control samples were prepared by adding 50 g of each thermally inhibited sample (that does not undergo ozone treatment) to 150 mL of tap water. The resultant slurry was stirred using a stir plate for 15 minutes, and then the pH was measured and recorded. [0102] The slurry was then dewatered through Whatman#4 filter paper using a Buchner funnel and vacuum pump. The starch cake in the Buchner funnel was rinsed by pouring 150 mL of tap water through the cake, before the cake cracked.

[0103] The cake was re-slurried with 150 mL of tap water, and the pH of the resultant slurry adjusted to 5 using approximately 6-8 mL of 5 weight % hydrochloric acid. The pH of the slurry was then recorded.

[0104] After 15 minutes, the slurry was then dewatered through Whatman#4 filter paper using a Buchner funnel and vacuum pump. The dewatered control was then exposed to 30 °C heat to dry until 10 weight % moisture content was achieved. The dried thermally inhibited, ozone treated sample was then grounded in a coffee grinder, and sifted through a No. 7 screen.

Example 1: Method of manufacturing a thermally inhibited, ozone treated starch or flour

[0105] In this non-limiting example of the present invention, the method of forming a thermally inhibited, ozone treated starch or flour is set out.

[0106] A method of forming an example thermally inhibited, ozone treated starch or flour followed the following steps:

1. Provide a thermally inhibited starch or flour.

2. Form a slurry containing water and the thermally inhibited starch or flour of step 1. The starch or flour is heated in water to above the gelatinisation temperature at a temperature of 25 °C. The concentration of the starch or flour in the slurry was 25 weight %. Typically, 0.11 kg (0.25 lbs) of thermally inhibited starch or flour is heated in 0.34 kg (0.75 lbs) of distilled water.

3. Stir the slurry for 10 to 15 minutes using a stir plate.

4. Measure the pH of the slurry and adjusting to he between a pH of 4.5 and 6.5. Sodium hydroxide at a concentration of 6 weight % in water was used to make the slurry more basic. Hydrogen chloride (HC1) at a concentration of 3 weight % in water was used to make the slurry more acidic.

5. Place the slurry in the tank of the ozone treatment apparatus (as shown in Figure 1).

6. Subject the slurry to ozone treatment by bubbling an air flow containing 0.5 weight % ozone when flowing at 26 LPM through the slurry.

7. Remove the slurry from the tank.

8. Dewater the slurry in a Buchner funnel using a Whatman#4 filter paper to form a cake from the slurry in the top of the Buchner funnel.

9. Pour 350 ml of tap water through the cake formed in the top of the Buchner funnel, before the cake cracked.

10. Suspend the cake in 350 ml water to reform a slurry.

11. Measure the pH of the slurry. The pH was adjusted to a pH of 5 by adding hydrochloric acid (HC1) at a concentration of 5 weight % in water.

12. Stir the slurry for 15 minutes using a stir plate.

13. Dewater the slurry in a Buchner funnel using a Whatman#4 filter paper to form a cake from the slurry in the top of the Buchner funnel. 14. Crumble the dewatered cake into an aluminium pan and place in an oven at 30 °C to dry until the cake has a moisture content of approximately 10 weight %.

15. Grind the dried starch or flour in a coffee mill for 30 seconds.

16. Sift through a No.7 screen to form a thermally inhibited, ozone treated starch or flour powder.

[0107] Control samples (non-ozone treated) were re-slurried and post- washed in the same way as described above.

Example 2: Comparison of the time of exposure to ozone treatment on the colorimetric values of the medium thermally inhibited, ozone treated starch

[0108] In this non-limiting example of the present invention, the length of time in which a slurry containing sample 1 (a medium thermally inhibited waxy com starch) was exposed to ozone was varied.

[0109] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to 4.5.

[0110] Three samples of the slurry were exposed to ozone for 30, 20 and 15 minutes, respectively.

[0111] The colorimetric parameters of the thermally inhibited, ozone treated starch samples were measured using a Hunter colorimeter, as set out above.

[0112] The control was subjected to the same treatment as the thermally inhibited, ozone treated starch except for exposure to ozone. The control was not exposed to ozone.

[0113] The process parameters and colorimetric parameters of each sample are displayed in Table 1 and Table 2, respectively. The pH indicated in Table 1 is the pH of the starch slurry prior to ozonation.

Table 1: Process parameters of Example 2.

Table 2: Colorimetric parameters of the thermally inhibited, ozone treated sample 1, and the thermally inhibited (non-ozone treated) sample 1 (the control).

[0114] As shown above, the longer the thermally inhibited starch is exposed to ozone, the closer the colorimetric parameters are to pure white.

Example 3: Comparison of the effect of different pH values of the slurry on the colorimetric parameters of the medium thermally inhibited, ozone treated starch

[0115] In this non-limiting example of the present invention, the effect of the pH of a slurry containing sample 1 (a medium thermally inhibited waxy com starch) on the colorimetric parameters upon ozone treatment was measured.

[0116] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to he at a pH of between 3.0 and 8.5 for different samples. Sodium hydroxide at a concentration of 6 weight % in water was used to make the slurry more basic. Hydrochloric acid (HC1) at a concentration of 3 weight % in water was used to make the slurry more acidic.

[0117] Samples of the slurry containing sample 1 were taken at each different pH, and each sample exposed to ozone for 15, 20 or 30 minutes, respectively.

[0118] The colorimetric parameters of the thermally inhibited, ozone treated starch were measured using a Hunter colorimeter, as set out above.

[0119] The process parameters of each sample are displayed in Table 3, and the colorimetric parameters of each sample are displayed in Table 4. Table 3: Process parameters of Example 3.

Table 4: Colorimetric values of sample 1 upon exposure to ozone for 15, 20 and 30 minutes, wherein the slurry containing sample 1 was at different pH values.

[0120] As shown in Tables 3 and 4, when the pH values he between 3.00 and 8.50 the colorimetric parameters of the thermally inhibited, ozone treated starch are close to white.

Furthermore, when a slurry containing sample 1 having a pH of 4.5, 5.5 and 6.5 was ozone treated for 15 minutes, the L colorimetric values achieved is greater than 95. Thus, the thermally inhibited, ozone treated starch is extremely close to white.

Example 4: Comparison of pH of the slurry on the colorimetric parameters of the high thermally, inhibited ozone treated starch [0121] In this non-limiting example of the present invention, the effect of the pH of a slurry containing sample 2 (a medium thermally inhibited waxy com starch) on the colorimetric parameters upon ozone treatment was measured.

[0122] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to he at a pH of between 6.5 and 7.5 for different samples. Sodium hydroxide at a concentration of 6 weight % in water was used to make the slurry more basic. Hydrochloric acid (HC1) at a concentration of 3 weight % in water was used to make the slurry more acidic.

[0123] Samples of the slurry containing sample 2 were taken different pH values, and each sample was exposed to ozone for 20 or 30 minutes, respectively.

[0124] The colorimetric parameters of the thermally inhibited, ozone treated starch were measured using a Hunter colorimeter, as set out above.

[0125] The control sample (i.e. non-ozone treated) was re-slurried and post washed in the same way as set out above. The pH of the control sample was adjusted to a pH of 6.5.

[0126] The process parameters of each sample are displayed in Table 5, and the colorimetric parameters of each sample are displayed in Table 6.

Table 5: Process parameters of Example 4.

Table 6: Colorimetric values of sample 2 upon exposure to ozone for 20 and 30 minutes, wherein the slurry containing sample 2 was at different pH values. [0127] As shown in Tables 5 and 6, when the pH values he between 6.5 and 7.50 the colorimetric parameters of the thermally inhibited, ozone treated starch are close to white

Example 5: Comparison of colorimetric values of a medium thermally inhibited post washed, short time ozone treated starch or flour to a thermally inhibited (non-ozone treated) starch

[0128] In this non-limiting example of the present invention, the colorimetric parameters of sample 3 (a medium inhibited, post-washed com sample) after ozone treatment were measured, and compared with a non-ozone treated control sample 3.

[0129] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to 6.5.

[0130] Samples of the slurry containing sample 3 were taken, and each sample was exposed to ozone for 4 or 7 minutes, respectively.

[0131] The colorimetric parameters of the thermally inhibited, ozone treated starch were measured using a Hunter colorimeter, as set out above.

[0132] The control sample (i.e. non-ozone treated) was re-slurried and post washed in the same way as set out above. The pH of the control sample was adjusted to a pH of 6.5.

[0133] The process parameters of each sample are displayed in Table 7, and the colorimetric parameters of each sample are displayed in Table 8.

Table 7: Process parameters of Example 5.

Table 8: Colorimetric values of sample 3 upon exposure to ozone for 4 or 7 minutes. [0134] As shown above, the longer the thermally inhibited starch is exposed to ozone, the closer the colorimetric parameters are to pure white. Furthermore, short exposure to ozone (i.e. less than 10 minutes) advantageously shows a L value greater than 92.

Example 6: Comparison of the viscosity of a medium thermally inhibited, ozone treated starch to the viscosity of a medium thermally inhibited (non-ozone treated) starch

[0135] In this non-limiting example of the present invention, the viscosity of a slurry containing sample 1 (a medium thermally inhibited waxy com starch) was measured and compared with the viscosity of a slurry containing sample 1 (but non-ozone treated).

[0136] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to be at a pH of 4.5, 5.5, 6.5 and 7.5 for four samples respectively. Sodium hydroxide at a concentration of 6 weight % in water was used to make the slurry more basic. Hydrogen chloride (HC1) at a concentration of 3 weight % in water was used to make the slurry more acidic.

[0137] Each sample was exposed to ozone for 15 minutes.

[0138] The viscosity of each of the four samples after ozone treatment was determined using a Rapid Visco Analyser (RVA) Perkins Elmer 4800 as set out above. [0139] The method of forming the thermally inhibited, non-ozone treated starch followed the method set out in example 1, without the ozone treatment step. The viscosity of the thermally inhibited, non-ozone treated starch was determined with the same procedure as set out above.

[0140] The results of the comparison are shown in Figure 2.

[0141] As shown in Figure 2, the viscosity of the slurry containing the thermally inhibited starch does not alter greatly upon exposure to ozone treatment. Therefore, the thermally inhibited, ozone treated starch does not functionally alter upon exposure to ozone treatment.

Example 7: Comparison of the viscosity of a medium thermally inhibited, ozone treated starch to the viscosity of a medium thermally inhibited (non-ozone treated) starch

[0142] In this non-limiting example of the present invention, the viscosity of a slurry containing sample 1 (a medium thermally inhibited waxy com starch) was measured and compared with the viscosity of a slurry containing sample 1 (but non-zone treated). Two samples were taken from the slurry, and exposed to ozone for different lengths of time. [0143] The method of forming the thermally inhibited, ozone treated starch followed the method set out in example 1. The pH of step 4 was adjusted to be at a pH of 8.5. Sodium hydroxide at a concentration of 6 weight % in water was used to make the slurry more basic. Hydrogen chloride (HC1) at a concentration of 3 weight % in water was used to make the slurry more acidic.

[0144] Each sample was exposed to ozone for 20 or 30 minutes respectively.

[0145] The viscosity of the slurry after ozone treatment was determined using a Rapid

Visco Analyser (RVA) Perkins Elmer 4800 as set out above.

[0146] The method of forming the thermally inhibited, non-ozone treated starch followed the method set out in example 1, without the ozone treatment step. The viscosity of the thermally inhibited, non-ozone treated starch was determined with the same procedure as set out above.

[0147] The results of the comparison are shown in Figure 3.

[0148] As shown in Figure 3, the viscosity of the slurry containing the thermally inhibited starch does not alter greatly upon exposure to ozone treatment. Regardless of the time in which the slurry containing the thermally inhibited starch is exposed to ozone, the viscosity does not alter greatly. Therefore, the thermally inhibited, ozone treated starch is not functionally altered upon exposure to ozone treatment, compared to a thermally inhibited, non-ozone treated starch.

Example 8: Comparison of the viscosity of a medium thermally inhibited, post washed ozone treated starch to the viscosity of a medium thermally inhibited (non-ozone treated) starch

[0149] In this non-limiting example of the present invention, the viscosity of a slurry containing sample 3 (a medium thermally inhibited, post-washed com sample) was measured and compared with the viscosity of a slurry containing sample 3 (but non-zone treated). Two samples were taken from the slurry, and exposed to ozone for different lengths of time. [0150] Each sample was exposed to ozone for 4 or 7 minutes respectively.

[0151] The viscosity of the slurry after ozone treatment was determined using a Rapid Visco Analyser (RVA) Perkins Elmer 4800 as set out above

[0152] The method of forming the thermally inhibited, non-ozone treated starch followed the method set out in example 1, without the ozone treatment step. The viscosity of the thermally inhibited, non-ozone treated starch was determined with the same procedure as set out above.

[0153] The results of the comparison are shown in Figure 4.

[0154] As shown in Figure 4, the viscosity of the slurry containing the thermally inhibited starch does not alter greatly upon exposure to ozone treatment. Regardless of the time in which the slurry containing the thermally inhibited starch is exposed to ozone, the viscosity does not alter greatly. Therefore, the thermally inhibited, ozone treated starch is not functionally altered upon exposure to ozone treatment, compared to a thermally inhibited, non-ozone treated starch.

[0155] The present technology pertains to thermally inhibited (alkaline roasted) starch or flour. In some embodiments ozone treated thermally inhibited starch or flour has a whiteness as described by HunterLab colorimetric parameters that is equal to the whiteness of a native starch or flour from the same base. In various other embodiments a thermally inhibited, ozone treated starch or flour has a HunterLab colorimetric parameters value of greater than about 92, or greater than 95. [0156] The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

[0157] Although certain example aspects of the invention have been described, the scope of the appended claims is not intended to be limited solely to these examples. The claims are to be construed literally, purposively, and/or to encompass equivalents.