Process for coating foodstuffs with stir-cooked, agglomerated wax starch

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] Disclosed herein are methods for making coated foodstuff, wherein the coatings are made from corn starch that expand on baking. More specifically, a method for coating made with a spray cooked, agglomerated waxy corn starch is disclosed herein.

[0002] Corn starch is widely used in manufactured foodsutffs (e.g. snack foods). It can be used as a sole starch component or mixed with other starches and flours. While corn starch is known to expand well during cooking, compared to other starches, like tapioca, it makes softer food snacks. It is desirable to have a corn starch that retains its favorable expansion characteristics while producing a harder foodstuff (e.g. snack food). US2004 / 067282 discloses the use of pregelatinized waxy maize starch to provide expanded, crispy, chip like textured coatings on an edible core material.

[0003] Disclosed herein is a method of making a coated foodstuff, wherein the foodstuff comprises an edible substrate and a coating comprising at least one layer of a coating mixture comprising a spray cooked agglomerated waxy corn starch as a first starch, baking the coated edible substrate at a temperature from 130° C and 190° for a time between 10 and 60 minutes. In one embodiment, the method of making a coated foodstuff comprises coating an edible substrate, wherein the a coating comprises at least one layer of a coating mixture comprising a spray cooked agglomerated waxy corn starch as a first starch as noted above and a second starch selected from a starch or flour. In a further embodiment, the first starch described herein has a time to peak hydration viscosity of between about 5.5 and about 7.5 minutes. In some embodiments, the coating described herein expands during baking to a coating expansion of between about 1.7 and about 2.6mm, between about 2.0 and about 2.5 mm, between about 2.125 and about 2.375 mm, or between about 2.2 and 2.3 mm. In other embodiments, the coating described herein has a hardness after being baked of between about 2500 and about 4000 grams, about 2500 and about 3800 grams, about 2600 and about 3800 grams, abut 2700 and about 3750 grams, about 2800 and about 3750 grams, about 2900 and about 3750 grams, about 3250 and about 3500, or about 3000 and about 3750 grams. In yet further embodiments, the coatings described herein have a hardness-to-expansion ratio of about 1100:1 to about 2200:1 g / mm. In other embodiments, the foodstuff in the method is a snack food. In some embodiments, the edible substrate is a nut, seed, legume, or vegetable. In yet other embodiments, the edible substrate has a moisture content of less than about 5% by weight.

[0004] Figure 1 is a graph depicting the hardness of a coating made from various starches set forth in Table 2.

[0005] Figure 2 is a graph depicting the coating expansion of coatings made from various starches set forth in Table 2.

[0006] As used herein, a "waxy starch" is derived from plants that naturally have low levels of amylose. The plants may be as found in nature, genetically modified, or bred through controlled breading programs. In some embodiments, the waxy starch of this invention has less than 10% by weight amylose, less than 5%, less than 3%, or essentially 0% amylose.

[0007] As used herein, an "agglomerated starch" is a starch composition comprising two or more starch particles bound together with a binding agent. Non-limiting examples of binding agents used in the art include sugar syrups, maltodextrin, water, and modified starch that have been at least partly dissolved in water. Such modified starch can be modified by pregelatinization, cross-linking, stabilization, hydrolysis or a combination thereof.

[0008] As used in herein, "unmodified", with regard to a starch or flour, means the starch or flour is not modified in any way such as by chemical, physical or enzymatic modification. For example, a pregelatinized starch is a modified starch.

[0009] A used herein, "cake flour" means one of a commercially available class of wheat flours that are bleached and are typically finer than commercially available all-purpose flours. Additionally, cake flour typically has a relatively low percentage, by weight of protein (around 8% versus 10%) compared to all-purpose flour.

[0010] As used herein, "coating expansion" refers to height of the coating measured from the inside edge of the coating to its outside edge after baking.

[0011] As used herein, "low protein flour" refers to flours having no more than about 8% protein by weight.

[0012] As used herein, the term "second starch" excludes a spray cooked agglomerated waxy corn starch.

[0013] Spray cooked, agglomerated starch is a pregelatinized starch made by a spray cooking process. Spray cooking is a process of cooking starch in a spray nozzle with a mixture of steam / slurry plus pressure followed by direct atomization into the spray chamber either as a fine particle that could be rewet agglomerated later or agglomerated within the spray dryer at the point of atomization.

[0014] Unless said otherwise, all ratios or percentages are by weight.

[0015] One embodiment is directed to a method for making a coated foodstuff comprising coating an edible substrate with a coating comprising at least one layer of a coating mixture comprising a spray cooked agglomerated waxy corn starch as a first starch, and baking the coated edible substrate at a temperature from 130° C and 190° for a time between 10 and 60 minutes. Another embodiment is directed to a method of making a coated foodstuff comprising coating an edible substrate with a coating comprising at least one layer of a coating mixture comprising a spray cooked agglomerated waxy corn starch as a first starch and a second starch selected from a starch or flour, wherein said edible substrate is coated with said coating. In one embodiment, the first starch described herein has a peak time to hydration viscosity of between 5.5 and 7.5 minutes or between about 6 and 7 minutes. In other embodiments, the first starch described herein has a median particle size (d50) of between about 150 and about 250 microns or between about 175 and about 225 microns. In still other embodiments, the first starch described herein has a d10 (10% of particles being smaller than) particle size distribution of between about 50 and about 100 microns or about 50 microns. In yet still further embodiments, the d90 (90% of particles being smaller than) is between about 325 and about 425 microns or between about 350 and about 400 microns. In still other embodiments, the first starch described herein has a volume mean particle size (D [4,3]) of between about 100 and 300 microns or between 150 and 250 microns.

[0016] Atomization during spray cooking controls the particle size. Size distribution of the agglomerated starches may also be controlled by using appropriate screening methods.

[0017] In one embodiment, the coating described herein is prepared from a coating mixture comprising a first starch and a second starch selected from starch and wheat flour, caked flour, low protein flour, and gluten containing flour. In one embodiment, the low protein flour described herein contains no more than about 8% protein by weight. In another embodiment, the coating mixture described herein comprises from about 50% of a first starch and 50% of a second starch or flour. In still another embodiment, the coating mixture described herein comprises from about 25% to about 75% of a first starch and from about 25% to about 75% of a second starch. In one embodiment, the first and second starch are mixed together to form a homogenous dry mixture. In still other embodiments, one or more coating mixture described herein comprises additional ingredients selected from a chemical leavening agent, such as, e.g. bicarbonate salts including for example sodium bicarbonate and ammonium bicarbonate; acid salts, including, for example, calcium phosphate and ammonium sodium sulfate; and tartaric acid. In yet still further embodiments, one or more coating mixture described herein comprises a leavening agent in an amount ranging from about 0.1% to about 1% by weight of the coating mixture. In even yet still further embodiments, one or more coating mixture described herein comprises sugar in an amount of from about 10% to about 40% of the coating mixture. In even still further embodiments, one or more coating mixture described herein comprises other seasoning and flavorings commonly used in a foodstuff including but not limited to salt.

[0018] In some embodiments, the second starch described herein is a starch and / or flour. In other embodiments, the second starch described herein is a wheat flour. In yet other embodiments, the second starch is a spray cooked, agglomerated starch other than a spray cooked, agglomerated waxy corn starch. In further embodiments, the spray cooked agglomerated starch other than a spray cooked, agglomerated waxy corn starch is a mixed starch or flour from oats, saga, corn, tapioca, pea or other pulse flours, barley, amaranth, arrowroot, canna, quinoa and sorghum, and waxy (i.e. low amylose), and high amylose variants of the foregoing. In an even further embodiment, the second starch is not pregelatinized or modified in any way. In still other embodiments, the second starch may be modified using standard modifications such as, for example, etherification, esterification, cross-linking, conversion, annealing, heat moisture treatment, thermal inhibition, and the like.

[0019] In some embodiments, the coating mixture is applied to the edible substrate with an adhesion layer comprising water or syrup made from sugar, gums, modified starches and starch derivatives, maltodextrins, and the like. In some embodiment, the syrup is a simple syrup comprising sugar and water. In other embodiments, the simple syrup is made by dissolving the sugar in water in a weight ratio of between about 1:4 sugar to water to about 4:1 sugar to water or the sugar to water ratio is about 1:1. In still other embodiments, the syrup further comprises other water soluble components, such as, for example, salt or chemical leavening agents of the types described above.

[0020] In yet further embodiments, the foodstuffs are coated using suitable methods known in the art. In some embodiments, a pan coater is used to coat an edible substrate with the adhesion layer and the coating comprising a first starch and optionally a second starch, which allows for alternating coatings of the adhesion layer and coating mixture layer. In still other embodiments, the coater applies substantially uniform coatings to the edible substrate. In still yet other embodiments, the edible substrate is coated more than once, by alternately coating it with the adhesion layer and the coating mixture. In some embodiments, more than 1 coating is used. In other embodiments, more than 5 coatings are used. In still other embodiments, more than 10 coatings are used.

[0021] In some embodiments, the method of making coated foodstuffs described herein involves baking in any type of industrial oven such as conventional ovens, fluidized bed reactors and driers, mixers and blenders equipped with heating devices, and other types of heaters. In the inventive method, the coated foodstuffs are subjected to baking at temperatures between 130 °C and 190 °C, preferably 150 °C and 180 °C, or around 170 °C. In the inventive method, the coated foodstuffs are baked for between 10 and 60 minutes, preferably between 20 and 30 minutes, around 25 minutes, or for 22 minutes.

[0022] In still other embodiments, the coated foodstuffs comprise a coating comprising at least one layer with a coating expansion of between about 1.7 and about 2.6mm, between about 2.0 and about 2.5 mm, between about 2.125 and about 2.375 mm, or between about 2.2 and 2.3 mm.

[0023] In yet other embodiments, the coated foodstuffs comprise a coating comprising at least one layer that has a hardness of between about 2500 and about 4000 grams, about 2500 and about 3800 grams, about 2600 and about 3800 grams, abut 2700 and about 3750 grams, about 2800 and about 3750 grams, about 2900 and about 3750 grams, about 3250 and about 3500, or about 3000 and about 3750 grams.

[0024] In some embodiments, the coating described herein has a hardness-to-expansion ratio of about 1100:1 to about 2200:1 g / mm, about 1500:1 to about 1600:1 g / mm, or about 1550:1 to about 1575:1 g / mm.

[0025] In some embodiments, the edible substrate described herein is any foodstuff that can be coated. In other embodiments, the edible substrate is selected from nuts (e.g. including almonds, cashews, etc.), seeds (e.g., sunflower seeds, fennel seeds, pumpkin seeds, etc.), legumes (peanuts, peas, etc.), and vegetables. In still other embodiments, the edible substrate described herein is dried, has a native moisture level, or is of a composition that little moisture transfers from the substrate to the coating prior to or during baking. In yet still other embodiments, the edible substrate described herein is fully cooked before being coated and baked. In yet even still further embodiments, the edible substrate described herein has a moisture content of less than about 5%.EXAMPLES Procedural protocols

[0026] Hardness measurements: Baked coatings were evaluated for hardness using a TA-XTPlus Texture Analyzer (Texture Technologies, Hamilton, MA) equipped with analytical software (Stable Microsystems, Surrey, UK). A 3 point bend rig was used for the measurement. The base of the rig had a 20 mm gap and the blade was 3 mm in diameter with a rounded edge. Conditions are listed in Table 1: Table 1 Test Mode Compression Pre-test Speed5 mm / secTest Speed20 mm / secPost-test Speed10 mm / secTarget ModeDistanceDistance15 mmTrigger TypeAutoTrigger Force20 gramsLoad Cell5 kg The measurements were taken for the peak force required to break the coating (in grams) and the distance to break (mm). A total of 30-35 samples were tested in order to get a full view of standard deviation (which typically ranged between 10-20%). After taking the measurements, the data was put through Minitab statistical software to remove outliers. A One-way ANOVA test with Tukey's LSD was used to identify statistical product groupings.

[0027] Volume measurements: Measured by measuring the volume of a defined number of whole coated peanuts (80 pieces) in a graduated cylinder.

[0028] Coating expansion measurements: Measured by hand using calipers. Results are based on the average thickness of coatings on 80 whole coated peanuts, wherein the peanuts were sliced open and the coating thereon measured from the outer surface of the coating to the inner surface of the coating. As used herein, the term "coating expansion" refers to the height of the coating measured from the inside edge of the coating to its outside edge after baking.

[0029] Hydration viscosity measurements: Measured with a Brabender ®< Micro Visco-Amylo-Graph ®< (manufactured by Brabender ®< GmbH & Co. KG, Duisburg, Germany). Measurements were made on a starch slurry of 4.5% starch solids, at pH 4. The slurry was heated to 30o C for 5 minutes, increased to 95o C and held for 15 minutes, and then cooled back down to 30o C. Time to peak viscosity is measured from the starting of mixing of the starch into solution (at 30o C) until slurry reaches peak viscosity.

[0030] Particle size: The particle size of the spray cooked, agglomerated waxy corn starch was measured by laser diffraction using a Malvern Mastersizer ®< 2000.

[0031] The starches used in the Examples that follow are set forth in Table 2. Table 2 Sample No Starch Type 1Drum dried waxy corn 12Drum dried waxy corn 23Drum dried waxy corn 34Drum dried waxy corn 45Spray cooked agglomerated waxy corn6Spray dried waxy corn starch7Drum dried waxy corn starch 58Pregelled, converted tapioca starch Example 1Peanut Coatings

[0032] Eight batches of coated peanuts were prepared in a coating process involving a coating mixture prepared from each of the Sample No 1-8 starches set forth in Table 2, adhesion layer, and peanuts in the components and weight percentages set forth in Tables 3 and 4. A coating mixture was prepared by mixing a Sample No 1-8 starch with wheat flour until homogenous. The adhesion layer was prepared by mixing sucrose and water together and heating until the sucrose completely dissolved. The adhesion layer was cooled before being used further. Table 3 Component Weight Percent of Total Adhesion Layer33%Peanuts32%Coating Mixture35% Table 4 Component Weight Percent of Total Adhesion LayerSucrose65%Water35% Coating MixtureOne Table 2 Starch50%Wheat Flour50%

[0033] The peanuts were coated by first dividing the peanuts, coating mixture, and adhesion layer into 7 parts. One part peanuts was added to a pan coater with one part adhesion layer and coating mixture and the contents mixed for 7 minutes to provide coated peanuts. This was repeated for each of the other 6 parts. The coated peanuts were baked in an oven for 25 minutes at 130°C. The baked peanuts were removed from the oven and cooled for 30 minutes before packing.

[0034] Figures 1 and 2 show that spray cooked agglomerated waxy corn starch (Sample No. 5 from Table 2) expanded to about 2.25 mm and had a hardness of about 3500 g.

Claims

1. A method of making a coated foodstuff comprising: coating an edible substrate with a coating comprising at least one layer of a coating mixture comprising a spray cooked, agglomerated waxy corn starch as a first starch; and baking the coated edible substrate at a temperature from 130° C and 190° C for a time between 10 and 60 minutes.

2. The method of claim 1 wherein: the edible substrate has a moisture content of less than about 5%.

3. The method according to any preceding claim, wherein said coating mixture further comprises a second starch.

4. The method according to any preceding claim, wherein the first starch has a peak hydration viscosity of between 5.5 and 7.5 minutes and wherein the peak hydration viscosity is measured as indicated in the specification.

5. The method according to claims 3 or 4, wherein the first and second starch are mixed in a weight ratio of between about 3:1 and about 1:3.

6. A method of making a coated foodstuff according to claim 1 wherein the edible substrate has a moisture content of less than about 5%; the coating comprises at least one layer of a mixture comprising a first starch characterized by being a spray cooked agglomerated waxy corn starch having a time to peak hydration viscosity of between 5.5 and 7.5 minutes and wherein the peak hydration viscosity is measured as indicated in the specification; and a second starch that is a starch or flour; and wherein the first and second starch are mixed in a weight ratio of between about 3:1 and about 1:3.

7. The method of any preceding claim, wherein said coating has a coating expansion of between about 1.7 and about 2.6 mm, between about 2.0 and about 2.5 mm, between about 2.125 and about 2.375 mm, or between about 2.2 and 2.3 mm.

8. The method of any preceding claim, wherein said coating has a hardness of between about 2500 and about 4000 grams, about 2500 and about 3800 grams, about 2600 and about 3800 grams, abut 2700 and about 3750 grams, about 2800 and about 3750 grams, about 2900 and about 3750 grams, about 3250 and about 3500, or about 3000 and about 3750 grams, after baking for 25 minutes at 130° C, and wherein the hardness is measured as indicated in the specification.

9. The method of any preceding claim, wherein said coating has a hardness-to-expansion ratio of about 1100:1 to about 2200:1 g / mm, about 1500:1 to about 1600:1 g / mm, or about 1550:1 to about 1575:1 g / mm, wherein the hardness is the hardness when the coated foodstuff after baking for 25 minutes at 130° C and wherein the hardness and expansion are measured as indicated in the specification.

10. The method of any preceding claim, wherein the edible substrate is a nut, seed, legume, or vegetable.

11. The method of any one of claims 3-10, wherein the second starch is a gluten free starch or wheat flour and said wheat flour is optionally unmodified.

12. The method of any one of claims 3-11, wherein said coating involves the application of 2 or more layers, 5 or more layers, 10 or more layers or up to 10 layers and said coating mixture comprises equal parts of said first starch and second starch, wherein said second starch is optionally unmodified wheat flour, wherein each layer is optionally adhered to the edible substrate with an adhesion layer comprising sucrose and water, wherein each layer is optionally adhered in a pan-coater for seven minutes, wherein said coating has a hardness-to-expansion ratio of about 1500:1 to about 1600:1 g / mm after baking coated foodstuff for 25 minutes at 130° C and wherein the hardness and expansion are measured as indicated in the specification.

13. The method of any preceding claim, wherein the first starch has a d50 of between about 150 and about 250 microns or between about 175 and about 225 microns; or d10 of between about 50 and about 100 microns; and optionally a d90 of between about 325 and about 425 microns or between about 350 and about 400 microns and wherein the particle size of the first starch are measured by laser diffraction.