BACKGROUND

[0001] Consumers increasingly want opportunities customize their experiences, including eating experiences. Creating food products that provide an enjoyable eating experience while being customized to individual eating preferences or dietary needs can be challenging. One way to individualize eating experiences is to use additive manufacturing (AM), also known as three-dimensional printing (3D printing), to allow consumers to build foods to their own specifications. Commercially available 3D printing technologies for AM of food rely on the use of extrudable ingredients, such as sauces and meltable confections, using a technique known as fused deposition modeling (FDM). However, although FDM technology has become an interesting way to customize food items, it cannot be used to 3D print food using ingredients that are typically in a dry or powdered form, such as whole grain ingredients, without modifying them so that they are extrudable. In addition, ingredients that are adaptable to FDM technology generally provide little in the way of structural integrity to food items made using FDM. As a result, ingredients that are 3D printed using FDM tend to be somewhat fragile and decorative, or require further processing (e.g., cooking) before they can be handled.

[0002] Another method of 3D printing edible items, called powder bed printing, relies on the selective deposition of a liquid binder on a powder bed. This technology has been successfully used to produce sugar-based 3D printed items. However, powder bed printing requires that at least some of the ingredients be able to be delivered in liquid form to the process. Another technology uses hot air to melt sugar in order to create three-dimensional sugar shapes. This technology is limited to ingredients that can be melted and recrystallized without burning. SUMMARY

[0003] The present disclosure relates to additive manufacturing of food pieces.

In an embodiment, provided herein is layered food piece that has at least two layers. The food piece includes a particulate whole grain ingredient including a bran component, where the particulate whole grain ingredient has at least 95% of its volume with a particle size less than 1000 μιτι. The food piece also includes a binder including a fat component and a carbohydrate component, where the binder has a melting temperature greater than

30° C and binds particles of the particulate whole grain ingredient together. Each layer of a food piece provided herein can have a thickness of at least 0.2 mm.

In some embodiments, the whole grain ingredient includes a whole wheat ingredient.

In some embodiments, the layered food piece has a volume of at least 4 mm ³ or at least 40 mm ³ .

[0004] In some embodiments, the starch from the particulate whole grain ingredient is at least 50% ungelatinized.

[0005] In another embodiment, a composition is provided that is formulated to form a

multilayered selective laser sintered food piece when exposed to selective laser sintering conditions. The composition includes a particulate whole grain ingredient and a particulate binder. The particulate whole grain ingredient includes a bran component and has at least 95% of its volume with a particle size less than 1000 μιη. The particulate binder ingredient that includes a fat component that melts at a temperature greater than 30° C and below 100° C, and a carbohydrate component that melts at a temperature greater than 70° C and below 250° C.

[0006] In some embodiments, the whole grain ingredient includes a whole wheat ingredient. The whole wheat ingredient can have at least 80% of its volume being a particle size range of ΙΟμηι to 1000 μιη.

[0007] In some embodiments, the fat component has an offset of melting that is within 25° C of onset of melting as measured by differential scanning calorimetry (DSC). In some embodiments, the offset of melting is within 10° C of peak heat flow on melting as measured by DSC. [0008] In some embodiments, the fat component has an offset of crystallization that is within 20° C of onset of crystallization as measured by DSC. In some embodiments, the onset of crystallization is within 10° C of peak heat flow on crystallization as measured by DSC.

[0009] In some embodiments, the fat component is an uncoated fully hydrogenated palm oil powder.

[0010] In some embodiments, the carbohydrate component is polydextrose.

[0011] In some embodiments a particulate whole grain ingredient is included in an amount of from about 10% to about 70% by weight of a composition provided herein, a fat component of the binder ingredient is included in an amount of from about 3% to about 10% by weight of the composition, and a carbohydrate component of the binder ingredient is included in an amount of from about 25% to about 65% by weight of the composition.

[0012] A composition provided herein can be proportioned and packaged in a container suitable for use with a selective laser sintering machine.

[0013] In another embodiment, a method of making a layered food piece is provided. The

method includes applying a laser to a first bed of selective laser sintering medium to form a first layer of the food piece, layering a second bed of the selective laser sintering medium on top of the first layer of the food piece, and applying a laser to the second bed to form a second layer of the food piece, the second layer of the food piece adhered to the first layer. The selective laser sintering medium includes a particulate whole grain ingredient including a bran component, and a particulate binder ingredient that includes a fat component and a carbohydrate component. The particulate whole grain ingredient has at least 95% of its volume with a particle size less than 1000 μιτι. The fat component melts at a temperature greater than 30° C and below 100° C. The carbohydrate component that at a temperature greater than 70° C and below 250° C.

[0014] In some embodiments, the whole grain ingredient includes a whole wheat ingredient. In some embodiments, at least 80% of the volume of the particulate whole wheat ingredient has a particle size range of Ι Ομιη to 1000 μιη. [0015] In some embodiments, the fat component has an offset of melting that is within 25° C of onset of melting as measured by DSC. In some embodiments, the offset of melting is within 10° C of peak heat flow on melting as measured by DSC.

[0016] In some embodiments, the fat component has an offset of crystallization that is within 20° C of onset of crystallization as measured by DSC. In some embodiments, the onset of crystallization is within 10° C of peak heat flow on crystallization as measured by DSC.

[0017] In some embodiments, the fat component is an uncoated fully hydrogenated palm oil powder.

[0018] In some embodiments, the carbohydrate component is polydextrose.

[0019] In another embodiment, a composition is provided herein that includes a flour ingredient and a particulate binder ingredient, and is formulated to form a multilayered selective laser sintered food piece when exposed to selective laser sintering conditions. The particulate binder ingredient includes a fat component that has a melting temperature of greater than 40° C and below 80° C and an offset of melting that is within 25° C of onset of melting as measured by DSC, and a carbohydrate component that melts at a temperature greater than 70° C and below 250° C.

[0020] In some embodiments, the offset of melting is within 10° C of peak heat flow on melting as measured by DSC.

[0021] In some embodiments, the fat component has an offset of crystallization that is within 20° C of onset of crystallization as measured by DSC. In some embodiments, the onset of crystallization is within 10° C of peak heat flow on crystallization as measured by DSC.

[0022] In some embodiments, the fat component includes an uncoated palm oil. In some

embodiments, the palm fat can be a fully hydrogenated whole palm oil or a fully hydrogenated palm oil fraction.

[0023] In some embodiments, the composition is proportioned and packaged in a container

suitable for use with a selective laser sintering machine. [0024] These and various other features and advantages will be apparent from a reading of the following detailed description.

BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 shows a sample graph of heat flow from a fat as measured by DSC as the fat is heated, and showing the onset of melting, offset of melting, and melting temperature.

[0026] Figure 2 shows a sample graph of heat flow from a fat as measured by DSC as the fat is cooled, and showing the onset of crystallization, offset of crystallization, and crystallization temperature.

[0027] Figure 3 shows examples of food pieces as provided herein.

[0028] Figure 4 illustrates a food piece placed on a 3-point bending rig.

[0029] Figure 5 is an image of a food piece provided herein with visible layers.

[0030] Figure 6 is an x-ray tomography image of a food piece provided herein with visible layers.

DETAILED DESCRIPTION

[0031] In light of the need for customized eating experiences, new technologies are needed to overcome the limitations of FDM, powder bed printing, and hot air facilitated printing.

[0032] Another way to 3D print objects is via a process known as selective laser sintering (SLS).

SLS uses a laser to fuse a particulate medium, and creates a three-dimensional item by fusing successive layers of the particulate medium atop one another.

[0033] Although SLS had previously been used to make food products as described in WO 2014/193226, it was discovered that particulate whole grain ingredients posed a particular challenge. That is, whole grain ingredients, such as whole corn flour, whole rice flour, and whole wheat flour, had a tendency to burn, as evidenced by smoke production, a burned smell, and/or excessive darkening of the whole grain ingredient, when used with SLS techniques previously described. [0034] Further research was needed to identify compositions and methods that could be used to produce an acceptable layered food piece that included a whole grain ingredient. This research determined that a combination of a particulate whole grain ingredient and a binder ingredient that included a carbohydrate component and a fat component could be included in a composition used to produce a multilayered food using SLS. However, it was surprisingly discovered that particle size of a whole grain ingredient could be adjusted to reduce or prevent burning of a layered food piece made during SLS and/or increase the strength of a food piece made with the whole grain ingredient. In addition, it was further discovered that a fat component that had a relatively sharp melting and crystallization profile could also improve food piece strength and/or reduce burning during SLS production of the food piece. When used alone, or in combination, these discoveries resulted in the ability to produce an acceptable layered food piece that contains a whole grain ingredient, where previous techniques resulted in unacceptable burning of the food piece and/or pieces that were unacceptably fragile.

Compositions

[0035] Provided herein are selective laser sintering medium (SLS medium) compositions, which contain a particulate whole grain ingredient (e.g., a flour) that includes a bran component that are formulated to form a multilayered selective laser sintered food piece when exposed to selective laser sintering (SLS) conditions. As used herein, a composition is considered to be formulated to form a multilayered selective laser sintered food piece when exposed to SLS conditions if the composition has the following characteristics:

• The composition consists of a free-flowing powder (i.e., having an angle of repose of less than 30°) at a temperature of less than 40° C prior to exposure to an SLS laser;

• At least 95% of the volume of the particles of the composition have a particle size of less than 2000 μηι;

• The composition transitions from a free-flowing powder to a fused, solid structure upon exposure to an SLS laser that heats at least a portion of the composition to a temperature of from about 100° C to about 200° C without substantial burning; and

• The composition forms layers of fused, solid structure that are fused to each adjacent layer upon multiple rounds of alternating exposure to an SLS laser and addition of the composition atop previous fused, solid structure layers.

[0036] As used herein, an "SLS laser" is any laser suitable for use in SLS. Examples include infrared C0 ₂ lasers and diode lasers. As used herein "SLS conditions" include exposure to an infra-red CO2 laser or diode laser for sufficient time to result in heating of at least one component (e.g., a particulate whole grain ingredient, a fat component, or a carbohydrate component) of a composition provided herein to a temperature of from about 100° C to about 200° C.

[0037] Surprisingly, it was found that burning could be reduced and the strength of multilayered food pieces could be increased when using a particulate whole grain ingredient in SLS if the particulate whole grain ingredient had at least 95% of its volume with a particle size of less than 1000 μιη (e.g., less than 900 μιη or less than 800 μιη), or where at least 80% of the volume of the particulate whole grain ingredient had a particle size between 10 μιη and 1000 μιη (e.g., between 10 μπι and 900 μηι or between 10 μιη and 800 μπι). In some embodiments, a whole grain ingredient can have at least 95% of its volume with a particle size of less than 600 μιη, or with at least 80% of its volume between about 10 μιη and about 600 μιη.

[0038] In some embodiments, a whole grain ingredient can benefit from having the bran component of the whole grain ingredient ground to result in the bran component having at least 95% of its volume with a particle size less than 1000 μιη, or having at least 80% of its volume being between about 10 μπι and 1000 μιη. In some embodiments, the fineness to which a whole grain ingredient and/or the bran component of a whole grain ingredient is ground to can be adjusted based on the relative pigmentation, particularly brown or black pigmentation, of the bran component. For example, a whole wheat flour with a red bran or white bran pigmentation can be ground to a larger average particle size (e.g., 95% volume having a particle size less than 1000 μιη), while a whole wheat flour with a black or dark brown bran can be ground to a finer average particle size (e.g., 95% volume having a particle size less than 900 μηι or less than 800 μιη) in order to result in a whole grain ingredient suitable for use in an SLS method.

[0039] Particulate whole grain ingredients suitable for use in a composition formulated to form a multilayered selective laser sintered food piece when exposed to selective laser sintering (SLS) conditions include those derived from cereal grains (e.g., wheat, corn, rice, wild rice, barley, oat, sorghum, and the like) and pseudocereal grains (e.g., quinoa, buckwheat, amaranth, and the like).

[0040] A particulate whole grain ingredient is included in a composition provided herein in an amount of from about 10% to about 70% (e.g., from about 30% to about 60%) by weight of the composition.

[0041] In addition to a particulate whole grain ingredient, compositions provided herein also include a binder ingredient. A binder ingredient includes a fat component and a carbohydrate component. While the particulate whole grain ingredient should not melt or burn when exposed to SLS conditions, at least a fat component in a binder ingredient melts when exposed to SLS conditions. In some embodiments, both a fat component and a carbohydrate component in a binder ingredient melt when exposed to SLS conditions.

[0042] Fats suitable for use in a binder ingredient provided herein include fats with melting temperatures between 30° C and 100° C (e.g., between 40° C and 80° C, or between about 55° C and about 65° C). In some embodiments, a suitable fat has a smoke point above 180° C (e.g., above 200° C). Examples of suitable fats include, without limitation, whole, fractionated, hydrogenated, or interesterified palm oil, palm kernel oil, lard, coconut oil, or combinations thereof. Preferably, a fat component includes low or no trans fatty acid content.

[0043] It was further discovered that burning could be reduced and the strength of multilayered food pieces could be increased when using a particulate whole grain ingredient in SLS if a binder that includes a fat component with a relatively sharp melting curve and/or crystallization curve is used. That is, as measured by differential scanning calorimetry (DSC) using a DSC-Q200 instrument (TA Instruments, New Castle, Delaware, USA) a fat component having an offset of melting that is within 25° C of onset of melting and/or an offset of crystallization that is within 20° C of onset of crystallization, is particularly useful in a binder for use in SLS.

[0044] As used herein, the term "onset of melting" when referring to a fat component refers to the temperature at which the fat component begins the phase transition from a solid to a liquid as the fat is heated at 7.5 ⁰ C per minute. As shown by example in FIG. 1 , the onset of melting appears as an initiation of a peak in heat flow at a temperature below the melting temperature of the fat as measured by DSC. Where multiple peaks in heat flow are observed, the onset of melting is the temperature at the initiation of the first (i.e., lowest temperature) peak. The melting temperature is the temperature at the peak at the highest temperature peak. As used herein, the term "peak" when referring to onset of melting, offset of melting, and melting temperature of a fat as measured by DSC refers to a peak in endothermic heat transfer. Depending on the orientation of the graph, a peak may appear as an upward peak (i.e., when the graph is oriented with endothermic up) or downward peak (i.e., when the graph is oriented with exothermic up).

[0045] As used herein, the term "offset of melting" when referring to a fat component refers to the temperature at which the fat component completes the phase transition from a solid to a liquid as the fat is heated at 7.5 ° C per minute. As shown by example in FIG. 1 , the offset of melting appears as a return to baseline heat flow at a temperature above the melting temperature of the fat as measured by DSC. Where multiple peaks are observed, the offset of melting is the temperature at return to baseline at a temperature above the last (i.e., highest temperature) peak.

[0046] As used herein, the term "onset of crystallization" when referring to a fat component refers to the temperature at which the fat component begins the phase transition from a liquid to a solid as the fat is cooled at 7.5 ⁰ C per minute. As shown by example in FIG. 2, the onset of crystallization appears as an initiation of a peak in heat flow at a temperature above the crystallization temperature of the fat as measured by DSC. Where multiple peaks in heat flow are observed, the onset of crystallization is the temperature at the initiation of the first (i.e., highest temperature) peak. The crystallization temperature is the temperature at the lowest temperature peak. As used herein, the term "peak" when referring to onset of crystallization, offset of crystallization, and crystallization temperature of a fat as measured by DSC refers to a peak in exothermic heat transfer. Depending on the orientation of the graph, a peak may appear as an upward peak (i.e., when the graph is oriented with exothermic up) or downward peak (i.e., when the graph is oriented with endothermic up).

[0047] As used herein, the term "offset of crystallization" when referring to a fat component refers to the temperature at which the fat component completes the phase transition from a liquid to a solid as the fat is cooled at 7.5 ⁰ C per minute. As shown by example in FIG. 2, the offset of crystallization appears as a return to baseline heat flow at a temperature below the crystallization temperature of the fat as measured by DSC. Where multiple peaks are observed, the offset of melting is the temperature at return to baseline at a temperature below the last (i.e., lowest temperature) peak.

[0048] A fat component is included as a component of a binder ingredient in a composition provided herein in an amount of from about 3% to about 10% (e.g., from about 4% to about 8%) by weight of the composition.

[0049] A carbohydrate component is included as a component of a binder ingredient in a composition provided herein. A carbohydrate component suitable for use in a binder ingredient is solid at a temperature at or below 40° C and melts at a temperature between about 70° C and about 250° C (e.g., between about 70° C and about 180° C, or between about 100° C and 245° C). Preferably, a carbohydrate component does not appreciably thermally decompose at a temperature below 200° C (e.g., below 150° C). Examples of carbohydrates suitable for use as a carbohydrate component in a binder ingredient include, without limitation, disaccharides (e.g., sucrose), polysaccharides (e.g., polydextrose and maltose), and sugar alcohols (e.g., isomalt and mannitol). A carbohydrate component can include one or a combination of suitable carbohydrates.

[0050] A carbohydrate component is included as a component of a binder ingredient in a composition provided herein in an amount of from about 25% to about 65% (e.g., from about 40% to about 50%) by weight of the composition.

[0051] In some embodiments, additional ingredients may be included in an SLS medium composition provided herein. Additional ingredients can be selected to provide desired properties to the composition itself (e.g., an anti-caking agent), or to a food piece made from the composition (e.g., vitamins, fiber, minerals, colorants, flavorants, and the like). In some embodiments, the ingredients included in an SLS medium composition can be specifically selected to impart a desired nutritional profile, appearance, flavor, and/or glucose response profile to a food piece made from the composition.

[0052] SLS medium compositions provided herein can be packaged into any appropriate packaging material, including packaging comprising paper, plastic, and/or metal. In some embodiments, an SLS medium composition can be portioned and packaged into a container suitable for use with an SLS machine. A container suitable for use with an SLS machine is enclosed to contain SLS medium in a free flowing state, and configured to deposit the SLS medium into the machine in a manner suitable for use in a method described herein upon opening. A container suitable for use with an SLS machine can be configured to contain sufficient SLS medium to produce one or more layered food piece. In some embodiments, a container suitable for use with an SLS machine is configured to be used only with a specific SLS machine type or design, similar to pods or containers designed for single-serve coffee machines (e.g., Nespresso or Keurig machines), or cartridges for ink printers.

Methods

[0053] Methods provided herein include applying SLS techniques to SLS medium compositions provided herein to form multilayered food pieces. A method provided herein includes applying a laser to a first bed of an SLS medium composition to form an initial food piece layer. Each additional layer of a layered food piece is produced by applying another bed of SLS medium on top of at least a portion of the previous food layer and applying a laser to each bed of SLS medium, such that each successive layer is adhered to the previous layer.

[0054] Depending on the laser type used (e.g., infra-red C0 ₂ laser or diode laser), different power settings, exposure lengths (the greater the laser pass speed, the lower the exposure time), and/or exposure number of the SLS medium to the laser can be used to achieve desired properties (e.g., reduced browning and/or increased layer strength) of a food piece layer produced by an SLS medium composition provided herein. For example, an infra-red C02 laser can be applied to an SLS medium bed at a power level of from 10% to 60% (e.g., 15% to 50%) of full power at a laser pass speed of 900 to 3000 mm per second (e.g., 1500 to 3000 mm/sec) to produce a food piece layer. In some embodiments, a bed of SLS medium can be exposed to more than one exposure of a laser (e.g., from 2 to 10, or 2-5) to produce a food piece layer. Generally, lower laser power settings (e.g., 15% to 30%) can be combined with higher exposure times (e.g., laser pass speed of 1500 mm/sec to 1800 mm/sec) and/or multiple exposures to arrive at a food piece layer that has reduced browning and/or increased layer strength. Conversely, a higher laser power setting (e.g., 30% to 50%) can be combined with lower exposure times (e.g., laser pass speed of 1800 mm/sec to 3000 mm/sec) and/or fewer laser exposures (e.g., 1 or 2 exposures) to produce a food piece layer with reduced browning and/or increased layer strength.

[0055] In some embodiments, laser power, exposure length, and/or exposure number can be adjusted based on the SLS medium composition used. For example, an SLS medium composition that includes whole corn may be exposed to a laser set at a power level of 15% to 30%, with a laser pass speed of 1200 to 1500 mm/sec, and 1 -3 passes to produce a food piece layer. In another example, an SLS medium composition that includes whole rice may be exposed to a laser set at a power level of 1 % to 30%, with a laser pass speed of 1200 to 3000 mm/sec, and 1 -3 passes to produce a food piece layer. In yet another example, an SLS medium composition that includes whole wheat may be exposed to a laser set at a power level of 15% to 40%, with a laser pass speed of 1200 to 3000 mm/sec, and 1 -5 passes to produce a food piece layer.

[0056] A bed of SLS medium can be applied such that it is at least about 3 mm (e.g., from about 3 mm to about 2 cm) deep. SLS medium depth can be adjusted as desired to result in a desired thickness of a food piece layer once a laser is applied to the bed. Generally, the greater the bed depth, the thicker the food piece layer. However, the power of the laser applied, or the time the bed of SLS medium is exposed to the laser, may need to be increased as bed depth increases in order to achieve desired food piece layer properties. Alternatively, additional passes of a laser may be used to achieve a desired level of consolidation of an SLS medium if a lower laser power or shorter exposure time is insufficient to produce the desired consolidation.

[0057] Bed depth and/or layer thickness need not be the same for each layer produced. In some embodiments, the SLS medium bed and/or the first layer produced during production of a food piece may be thicker than subsequent layers, or layer thicknesses can be varied throughout the food piece.

[0058] Each layer can be made from the same or a different SLS medium composition as the previous or following layer. For example, several layers may be made of an SLS medium composition that includes a whole grain rice ingredient, then additional layers may be made of an SLS medium that contains a combination of whole wheat and whole barley. In another example, each layer may alternate with different whole grain ingredients. In another example, layers formed from an SLS medium composition containing a whole grain ingredient may be made followed by layers formed from an SLS medium composition described in WO 2014/193226.

[0059] Once a food piece is produced, it can be removed from surrounding unsintered medium.

Food Pieces

[0060] Food pieces can be made in any shape desired. Examples of shapes include solid or hollow free-form shapes, spheres, cubes, shapes resembling objects (e.g., cars or trees), and the like. Some examples of food piece shapes are shown in Fig. 3. If a hollow form is desired, the shape should include one or more hole for any unsintered medium to escape, unless it is desired to retain unsintered medium within the shape.

[0061] A food piece produced using a method and materials provided herein have at least 2 layers (e.g., 3 or more layers), with each layer being at least 0.2 mm (e.g., 0.2 to 1 mm) thick. Food piece layers can be visualized directly or using x-ray tomography, as shown in Figs. 5 and 6, respectively.

[0062] A food piece produced using a method and materials provided herein can be made for any appropriate eating occasion. For example, a food piece can be used as a ready-to-eat cereal piece, a snack, a dessert, and the like.

[0063] Preferably, a food piece provided herein is sturdy, and may be easily handled without substantial damage. In some embodiments, the mechanical strength of a food piece provided herein can be measured using a 3-point bending test. Specifically, a food piece having 3 or more layers can be placed on a three point bending rig as shown in Fig. 4, and the mechanical strength can be measured using a TA.XTPlus Texture Analyser (Texture Technologies, Hamilton, Massachusetts, USA) set with the settings shown in Table 1. In some embodiments, a food piece having at least 3 layers tested using the 3-point can break at a distance of at least 0.3 mm and/or with a force of at least 0.2 N.

Table 1

[0064] In some embodiments, a food piece provided herein can be combined with other food pieces to form larger structures. For example, food pieces provided herein can be combined with similarly produced food pieces and/or food pieces or items not made using SLS techniques. In some embodiments, a food piece provided herein can be used to decorate a food item or other non-edible item.

[0065] The implementations described above and other implementations are within the scope of the following claims. One skilled in the art will appreciate that the present disclosure can be practiced with embodiments other than those disclosed. The disclosed embodiments are presented for purposes of illustration and not limitation.