EDIBLE COMPOSITES, METHODS OF FORMING AND DEVICES

THEREOF

Technical Field of the Invention

The present invention relates to edible composites, methods of forming edible composites and devices thereof. In particular, the present invention relates to extruded edible composites, methods of forming and devices thereof. Background

As economies progress and societies become more affluent, people tend to take in a diet richer in simple carbohydrates, especially in Asia. This has led to many health issues and lifestyle problems such as diabetes, cardiovascular diseases, high cholesterol and obesity. It is recognised that one way to achieve a better wellbeing is by maintaining a low glycaemic index (GI) diet.

The glycaemic index is a scale that ranks carbohydrates (from 0 to 100) based on the extent to which the carbohydrates raise blood sugar (glucose) levels over a period of time after eating. High GI foods (more than 70) are rapidly digested, absorbed and metabolised, and accordingly can result in a spike in blood sugar over a short period of time. Low GI food (less than 55) is more slowly digested, absorbed and metabolised. This causes a lower and slower rise in blood glucose and insulin levels. It is believed that by managing blood glucose levels, a better general wellbeing state can be achieved. In this regard, a low GI diet has shown to be helpful for people suffering from diabetes (type 1 and 2), gestational diabetes, high cholesterol, weight management issues and heart diseases.

However, while low GI food is advantageous for health, there is still resistance by the public with regards to its consumption. This is because low GI food needs to be processed or cooked gently as the processing and cooking method can break down the low GI carbohydrates, resulting in a higher GI food. Further, low GI food is often not palatable. The gentle cooking and processing of low GI food also means that such food is lacking in terms of texture profile and taste. For example, shirataki noodles are made from konjac fibre and by themselves have no or little flavour. Shirataki noodles are sold in either dry or wet (packaged in liquid) forms and has a gelatinous texture. Shirataki noodles have a bitter taste and require rinsing or parboiling to reduce their unpleasant odour. Accordingly, shirataki noodles are often cooked in a very flavourful soup or sauce, which may diminish the advantage of a low GI diet. Further, they have a shelf life of less than one year, which is not ideal for a packaged food.

Low GI ingredients are also not easy to handle and process. For example, during dough making, low GI carbohydrates do not form gluten easily, causing the dough to be powdery and fall apart.

There is also no presently available means for forming food products in the comfort of home and which is relatively simple to use, prepare or clean.

Accordingly, it is generally desirable to overcome or ameliorate one or more of the above mentioned difficulties, or at least to provide a useful alternative.

Summary

According to the present invention, there is provided a method of forming an edible composite, including :

a) providing at least one extrusion component having a first channel and a second channel, an end of the second channel extending at least partly into the first channel, the at least one extrusion component having a liquid contact zone that is adjacent to the end of the second channel;

b) introducing a first liquid into the first channel at a first flow condition;

c) introducing a second liquid into the first channel or the second channel at a second flow condition, such that the second liquid combines with the first liquid at the liquid contact zone to form a combined liquid; and

d) solidifying the combined liquid to form the edible composite.

Advantageously, by allowing the two liquid components to at least combine and subsequently solidify, multiple ingredients can be put together to form an edible composite with nutritional value. By controlling the flow conditions, functional ingredients can be encapsulated and the textures of the edible composites can be customised. This also allows nutritional ingredients with an unpleasant taste profile to be masked. Accordingly, the edible composites formed using this method can be arranged to be both healthy (e.g. medium GI index (between 69 to 56) or low GI index (less than 55)) and palatable.

In some embodiments, at least one of the first liquid or the second liquid includes a gelling type hydrocolloid.

In some embodiments, the gelling type hydrocolloid is selected from the group consisting of alginate, pectin, carrageenan, gelatin, gellan, agar, modified starch, methyl cellulose, hydroxypropyl methyl cellulose and protein isolate.

In some embodiments, the first flow condition and the second flow condition are selected to produce one or more desired textural properties of the edible composite.

In some embodiments, the desired textural properties are selected from the group consisting of hardness, cohesiveness, springiness, chewiness and resilience.

In some embodiments, the first flow condition and the second flow condition are selected according to a mathematical model in which the first and second flow conditions are stimuli, and the one or more desired textural properties are responses.

In some embodiments, the flow condition is selected from the group consisting of flow rate, concentration or a combination thereof.

In some embodiments, the method further includes a step (ci) of mixing the combined liquid prior to step (d).

In some embodiments, the mixing occurs by diffusion across the interface of the first liquid and the second liquid.

In some embodiments, the combined liquid is solidified by a gelling agent, a change in temperature or a combination thereof. In some embodiments, the at least one extrusion component comprises a kink, bend or necking in the first channel and/or the second channel. In some embodiments, step (c) includes introducing a second liquid into the second channel such that the combined liquid flows through a downstream portion of the first channel.

In some embodiments, step (c) includes introducing a second liquid into the first channel such that the combined liquid flows through a downstream portion of the second channel.

In some embodiments, the method further includes a step (cii), prior to step (d), of providing a second extrusion component having a third channel, a second end of the second channel of the at least one extrusion component extending at least partly into a third channel of a second extrusion component, the second extrusion component having a second liquid contact zone that is adjacent to the second end of the second channel; introducing a third liquid into the third channel at a third flow condition such that the third liquid combines with the combined liquid at the second liquid contact zone to form a second combined liquid.

In some embodiments, the edible composite comprises:

a) an outer component; and

b) an inner component, the inner component adjacent to the outer component; wherein the outer component envelops the inner component.

In some embodiments, the inner component is selected from the group consisting of protein, oil, dietary supplement, food additive, vitamin, mineral, herb and dairy product. In some embodiments, the outer component is a gelling type hydrocolloid.

The present invention also provides a device for forming an edible composite, comprising :

at least one processor in communication with machine-readable storage; at least one extrusion component having a first channel and a second channel, an end of the second channel extending at least partly into the first channel, the at least one extrusion component having a liquid contact zone that is adjacent to the end of the second channel; and

at least one pump in communication with the at least one processor;

wherein the machine-readable storage has stored thereon machine-readable instructions which, when executed by the at least one processor, cause the at least one pump to:

pump a first liquid into the first channel at a first flow condition;

pump a second liquid into the first channel or the second channel at a second flow condition, such that the second liquid combines with the first liquid at the liquid contact zone to form a combined flow; and

pump the combined flow to a solidification component to solidify the combined flow to thereby form the edible composite.

Advantageously, the device allows for an on-demand means to form edible composites. Instead of packaging and storing the edible composite, the edible composite can be formed as and when needed. This overcomes the problem of shelf-life. Further, a consumer can, for example through a programme which stores parameters, to explore a range of textures and ingredients thereby creating an edible composite that matches his preferences, thereby allowing for personalised nutrition.

In some embodiments, the solidification component comprises a gelling bath.

Brief Description of the Drawings

Embodiments of the present invention are hereafter described, by way of non-limiting example only, with reference to the accompanying drawings in which :

Figure 1 is a schematic sectional view of an extrusion component;

Figure 2 is a schematic sectional view of an extrusion component in a co-flow setup;

Figure 3 is a schematic sectional view of an extrusion component in a counter-flow setup; Figure 4 is a schematic sectional view of two extrusion components in tandem, and in a co-flow and counter-flow setup;

Figure 5 is a flow chart relationship between stimuli and responses;

Figure 6 is an image of an edible composite formed using a co-flow setup at a perspective viewing angle and at 1.6X magnification;

Figure 7 is an image of an edible composite formed using a co-flow setup at 2.5X magnification;

Figure 8 is an image of an edible composite formed using a co-flow setup with a necking device at a perspective viewing angle and at 1.6X magnification; Figure 9 is an image of another edible composite formed using a co-flow setup with a necking device at a perspective viewing angle and at 1.6X magnification;

Figure 10 is an image of an edible composite formed using a counter-flow setup at a perspective viewing angle and at 1.6X magnification;

Figure 11 is an image of an edible composite formed using a counter-flow setup at

2.5X magnification;

Figure 12 is an image of an edible composite formed using a tandem co-flow and counter-flow setup at a perspective viewing angle;

Figure 13 is an image of an edible composite formed using a tandem co-flow and counter-flow setup at 2.5X magnification;

Figure 14 is a table of the resultant textural properties using a co-flow setup; Figure 15 is a table of the resultant textural properties using a co-flow setup in a forward design model;

Figure 16 is a table of the input and output textural properties using a co-flow setup in a reverse design model;

Figure 17 is a schematic diagram of a device for forming an edible composite; Figure 18 is a flow diagram of a method for forming an edible composite;

Figure 19 is a plot of textural properties change of an exemplary edible composite over time;

Figure 20 is a plot of textural properties change of an exemplary edible composite over time;

Figure 21 illustrates the average plasma glucose change in subjects over time; Figure 22 shows the mean postprandial incremental area under curve (iAUC) of glucose responses; and

Figure 23 illustrates the overall sensory evaluation of edible composites. Detailed Description of Embodiments of the Invention

Embodiments of the present invention provide a method of forming an edible composite.

For example, with reference to Figure 1 and Figure 18, a method 1800 may include providing (step 1810) at least one extrusion component 100 having a first channel 102 and a second channel 104. An end 106 of the second channel 104 extends at least partly into the first channel 102. The at least one extrusion component 100 has a liquid contact zone 108 that is adjacent to the end 106 of the second channel 104. A first liquid can be introduced (step 1820) into the first channel 102 at a first predefined flow condition and a second liquid can be introduced (step 1830) into the first channel 102 or the second channel 104 at a second predefined flow condition, such that the second liquid combines with the first liquid at the liquid contact zone 108 to form a combined liquid. The combined liquid is subsequently solidified (step 1840) to form the edible composite. The solidification process can occur downstream 110 from the liquid contact zone 108.

As used herein, 'liquid' refers to a flowable material but excludes gas. In this regard, non-newtonian fluids such as custard, honey, ketchup and whipped cream are included within this definition. Fluids with time dependent viscosity such as yogurt and peanut butter are also included within this definition. Materials that can become flowable due to a change in physical parameter are also included. An example is molten chocolate.

As used herein, 'liquid contact zone' refers to the region in which the liquids first come into contact with each other to form a singular output. As will be apparent from the description below, as the output flows away from the liquid contact zone, if an interfacial tension is present between the first and second liquid in the combined liquid, the interface is maintained and the gelled product can be have distinct layers. Alternatively, the first and second liquid in the combined liquid can be subjected to complete or partial mixing.

Figure 2 shows an example of the liquids in a co-flow setup. The extrusion component 200 has a first channel 202, a second channel 204, an end 206 of the second channel 204 and liquid contact zone 208. A first liquid 212 can be introduced into the first channel 202 at a first predefined flow condition. The first liquid 212 can be introduced at one end of the first channel 202. A second liquid 214 can be introduced into the second channel 204 at a second predefined flow condition. The second liquid can be introduced at an opposite end to end 206. When the second liquid 214 combines with the first liquid 212 at the liquid contact zone 208, a combined liquid is formed. This combined liquid then flows pass 210 and is solidified to form the edible composite.

Figure 3 demonstrates a counter-flow setup, in which the flow direction of the second liquid is altered. A first liquid 312 can be introduced into the first channel 302 at a first predefined flow condition. A second liquid 314 can be introduced into the first channel 302 at a second predefined flow condition. The second liquid 314 can be introduced at an opposite end to 312. When the second liquid 314 combines with the first liquid 312 at the liquid contact zone 308, a combined liquid is formed. This combined liquid then flows through the second channel 304 to a downstream portion 310 and is solidified to form the edible composite.

The advantage of this method lies in that two liquid components are used and allowed to at least combine. By doing so, multiple ingredients can be put together to form an edible composite with nutritional value. As the liquid components have low or at least manageable viscosity, by controlling the flow conditions, functional ingredients can be encapsulated and the textures of the edible composites can be customised. This also allows nutritional ingredients with an unpleasant taste profile to be masked. Accordingly, the edible composites formed using this method can be both healthy (e.g. low GI index) and palatable. Further, when used in a home appliance, the use of liquid components makes it easier to clean as compared to one that uses dough.

For the combined liquid to solidify into an edible composite, at least one of the first liquid 212 or the second liquid 314 includes a gelling type hydrocolloid. For example, the first liquid 212 can include a gelling type hydrocolloid. In this regard, when the combined liquid is placed under conditions favourable for solidifying, the first liquid can form a gel matrix which envelops the second liquid. This traps the second liquid within the gel matrix. Alternatively, the second liquid 314 includes a gelling type hydrocolloid which at the liquid contact zone 308 forms a combined liquid which then flows through 310. The gelling type hydrocolloid thus allows for the solidification of the edible composite as it exits the extrusion component or when it enters the gelling bath. Alternatively, the first liquid and the second liquid can both separately include a gelling type hydrocolloid. This can provide additional textural or mouth feel to the edible composite. For example, when extruded using the co-flow setup in Figure 2, the first liquid 212 can gel to give a different resilience (or springiness, chewiness, hardness) to the gelled second liquid 214.

With the gelling of the liquids, the unique flow pattern is preserved, giving unique textural properties and nutrient release profiles of the edible composite. By using different gelling type hydrocolloids in the first and second liquid, variations in textures can be obtained.

Gelling type hydrocolloids, as used herein, refers to hydrocolloids that are capable of forming a gel. Such are a heterogeneous group of long chain polymers (polysaccharides and proteins) characterised by their propensity to form gels under the right conditions. They have a large number of hydroxyl (-OH) groups which markedly increases their affinity for binding water molecules rendering them hydrophilic compounds. In water, they produce a dispersion, which is intermediate between a solution and a suspension, and exhibits the properties of a colloid. Gelling type hydrocolloids form gels by physical association of their polymer chains through hydrogen bonding, hydrophobic association and cation mediated cross-linking, thereby trapping water within its tangled and interconnected molecular network. In this regard, gelling type hydrocolloids form a gel when they come into contact with a gelling agent and/or experience a suitable gelling condition. For example, alginates can gel in the presence of a gelling agent such as calcium chloride. Agar can gel when it experiences a change in temperature, for example from about 85 °C to about 32 to 40 °C.

The word 'gel' refers to a substance which retains its shape when released from its container.

The gelling type hydrocolloid can include, without limitation, alginate, pectin, carrageenan, gelatin, gellan, agar, modified starch, methyl cellulose, hydroxypropyl methyl cellulose and protein isolate. In other embodiments, the gelling type hydrocolloid can be selected from the group consisting of alginate, pectin, carrageenan, gelatin, gellan, agar and protein isolate. In some embodiments, the gelling type hydrocolloid is sodium alginate. The first liquid can additionally include, without limitation, protein, carbohydrates, oil, dietary supplement, food additive, vitamin, mineral, herb extract, food flavours, phytochemicals, dairy product and their combinations thereof. The second liquid can include, without limitation, a gelling type hydrocolloid, carbohydrates, protein, oil, dietary supplement, food additive, vitamin, mineral, herb extract, food flavours, phytochemicals, dairy product and their combinations thereof. In an example, the second liquid includes protein isolate. The first flow condition and the second flow condition can be selected to produce one or more desired textural properties of the edible composite. For example, the flow condition can be selected from the group consisting of flow rate, or concentration.

The flow condition can be a flow rate from about 0.1 pLymin to about 30000 pL/min, from about 0.5 pL/min to about 30000 pL/min, from about 1 pL/min to about 25000 pL/min or from about 1 pL/min to about 20000 pL/min. Alternatively, the flow rate can be from about 2 pL/min to about 15000 pL/min, about 2 pL/min to about 10000 pL/min, about 2 pL/min to about 5000 pL/min, about 2 pL/min to about 4000 pL/min, about 2 pL/min to about 2000 pL/min, about 2 pL/min to about 1000 pL/min or about 2 pL/min to about 500 pL/min. In some embodiments, the flow rate is about 350 pL/min.

For example, the first flow condition can be a flow rate from about 100 pL/min to about 30000 pL/min, about 100 pL/min to about 20000 pL/min, about 100 pL/min to about 10000 piymin, about 100 pL/min to about 5000 pL/min, about 100 pL/min to about 3000 pL/min, about 100 pL/min to about 2000 pL/min, about 100 pL/min to about 1000 pL/min, or about 100 pL/min to about 500 pL/min.

For example, the second flow condition can be a flow rate from about 0.1 pL/min to about 20000 pL/min, about 1 pL/min to about 10000 piymin, about 2 pL/min to about 5000 pL/min, about 2 pL/min to about 1000 pL/min, about 2 pL/min to about 500 pL/min, or about 2 pL/min to about 300 pL/min.

In some embodiments, the first flow condition is a flow rate of about 4200 pL/min and the second flow condition is a flow rate of about 700 pL/min. Taking reference from Figure 14, the first flow rate can be about 310 pL/min and the second flow rate can be about 40 pL/min, the first flow rate can be about 200 pL/min and the second flow rate can be about 150 pL/min, the first flow rate can be about 260 pL/min and the second flow rate can be about 90 pL/min, the first flow rate can be about 120 pL/min and the second flow rate can be about 230 pL/min, the first flow rate can be about 330 pL/min and the second flow rate can be about 20 pL/min, or the first flow rate can be about 190 pL/min and the second flow rate can be about 160 pL/min.

In some embodiments, the combined (first flow rate and second flow rate) flow rate can be about 30000 pL/min, about 25000 pL/min, about 20000 pL/min, about 15000 mI_/Ghίh, about 10000 pL/min, about 8000 mI_/Ghίh, about 5000 pL/min, about 3000 mI_/Ghίh, about 2000 pL/min, about 1000 pL/min, about 800 pL/min, about 500 mI_/Ghίh or about 200 pL/min. In some embodiments, the combined flow rate is about 350 pL/min.

The relative flow rate of the first liquid to the second liquid can be from about 20: 1 to about 0.2: 1, or about 9: 1 to about 1 : 1, or about 9: 1 to about 2: 1, or about 9: 1 to about 3: 1, or about 9: 1 to about 4: 1, or about 9: 1 to about 5: 1, or about 9: 1 to about 6: 1. As exemplified in Figure 14, the relative flow rate can be from about 20: 1 to about 0.1 : 1, or about 0.5: 1, about 1 : 1, about 1.5: 1, about 3: 1, about 7: 1, about 7.5: 1 or about 18: 1.

The flow condition can be a concentration from about 0.5 %w/v to about 90 %w/v. For example, the first liquid can have a gelling type hydrocolloid from about 0.5 %w/v to about 90 %w/v, or about 0.5 %w/v to about 80 %w/v, or about 0.5 %w/v to about 60 %w/v, about 0.5 %w/v to about 40 %w/v, or about 0.5 %w/v to about 25 %w/v, or about 0.5 %w/v to about 10 %w/v, or about 0.5 %w/v to about 5 %w/v. For example, the second liquid can have a protein isolate from about 1 %w/v to about 80 %w/v, or about 5 %w/v to about 70 %w/v, or about 5 %w/v to about 60 %w/v, about 5 %w/v to about 40 %w/v, or about 5 %w/v to about 30 %w/v, or about 5 %w/v to about 20 %w/v, or about 5 %w/v to about 15 %w/v.

The relative mass ratio of the component(s) in the second liquid to the component(s) to the total mass can be from about 20% to about 90%. The first liquid and the second liquid contact each other at the liquid contact zone and form a combined liquid downstream from the liquid contact zone. In this regard, the first and second liquids in the combined liquid may be still distinct from each other; i.e. the interface between the first and second liquid is maintained.

The combination can be by the first and second liquids flowing laminarly with respect to each other. Accordingly, the components in the first and second liquids are also distinct from each other. In this regard, there is no mixing between the two liquids.

Figure 6 and 7 show examples of an edible composite in which the first and second liquid were combined in a laminar manner. In the resultant edible composite, the boundary between the solidified alginate and the emulsion can be clearly seen.

The combined liquid (first and second liquid) can be further partially or completely mixed. In this regard, the method can further include a step (ci) of mixing the combined liquid prior to step (d). The mixing can be by laminar mixing and occurs downstream from the combined liquid. The term 'mixing' refers to blending or mingling of the components in the combined liquid such that the interface between the first and second liquids is partially disturbed or completely eliminated.

Laminar mixing is characterised by fluid particles following smooth paths in layers, with each layer moving smoothly past the adjacent layers. While the first and second liquids are moving parallel to each other, the components, being in the same water medium and under certain conditions, can diffuse across the boundary via a concentration gradient. In this regard, laminar mixing occurs by diffusion mixing between the interface of the first liquid and the second liquid, and can for example occur at a perpendicular direction relative to the length of the channel. Accordingly, mixing occurs when the component in the first liquid moves into the second liquid and vice versa.

Mixing can also occur due to the instability at the interface. This is termed as Plateau- Rayleigh instability. The driving force of the Plateau-Rayleigh instability is that liquids, by virtue of their surface tensions, tend to minimize their surface area. This is due to the existence of small perturbations in the liquid no matter how smooth the stream is. The perturbations can be resolved into sinusoidal components, which can grow with time. The instability at the interface can favour mixing of the liquids. The mixing can occur downstream from the liquid contact zone and can be influenced by factors such as the length of tubing, the overall flow velocity and time. In this regard, the combined liquid can be manipulated before solidification to form the edible composite. For example, by increasing the length of tubing after the liquid contact zone, the liquids have more time to commingle.

Figure 11 shows an example of an edible composite in which mixing has occurred via both diffusion and Plateau-Rayleigh instability, by virtue of the counter-flow setup. The boundary between the first and second layers is not as distinct compared to Figure 7.

The first channel and/or the second channel can further include kinks, bends or neckings. For example, as shown in Figure 1, the second channel 104 can include a tapered end 106. This tapering allows for further control of the flow dynamics and regulation. The tapered end also allows for an edible composite with a certain textural profile. It also prevents the second liquid from spraying out from the second channel and allows for an edible composite which is reproducible. While a tapered end is exemplified, the skilled person would understand that other morphologies may also be suitable for use.

The mixing can be initiated by a kink or necking in the first or second channel after the liquid contact zone, for example at 110 of Figure 1.

Figure 8 and 9 show examples of an edible composite formed using a co-flow setup. A necking modification can be introduced (for example at 110 of Figure 1) to create an instability at the liquid interface between the first and second liquids but the components in the first and second liquids are still distinct from each other. When the edible composite is formed, the 'disturbed' interface is preserved. The first channel 102 can have an inner diameter xi from about 0.1 mm to about 5 mm. The second channel 104 can have an inner diameter X2 from about 0.1 mm to about 3 mm. The second channel 104 can be extended (X3) into the first channel 102 from about 0.1 mm to about 50 m. The tapered end 106 of the second channel 104 can have an inner diameter X4 from about 0.001 mm to about 2 mm. An end of the first channel 102 at 110 can be connected to a tubing or capillary to extend the travelling distance xs. The travelling distance X5 of the first channel 102 from the liquid contact zone 108 can be from about 0.1 mm to about 100 m. An end of the second channel 104 extending from X6 can be extended from about 0.1 mm to about 100 m. It will be understood that the extrusion component can be connected to other tubings and connectors with suitable sizes and dimensions such that there is minimal or no leakage. For example, an end of the second channel extending from xe can be connected to a tubing or capillary with an inner diameter of about 0.1 mm to about 5mm.

The extrusion component is set up such that the inner diameter xi is more than the combination of the inner diameter X2 and the wall thickness of the second channel. The inner diameter X2 is more than the inner diameter of the tapered end X4.

In an example, xi is 1 mm, X2 is 0.76 mm, X4 is 0.15 mm and X5 is 7 mm.

More than one extrusion component can be used to form the edible composite. For example, Figure 4 illustrates two extrusion components in tandem. The extrusion components are set up in a manner such that one extrusion component allows for counter-flow and the other for co-flow. In this regard, the method can further include a step (cii) prior to step (d) of providing a second extrusion component having a third channel 404, an end 408 of the second channel 420 of the at least one extrusion component extending at least partly into the third channel 404, the second extrusion component having a second liquid contact zone 410 that is adjacent to the end 408 of the second channel 420 of the at least one extrusion component. The first liquid 414 and second liquid 416 is introduced into at least one extrusion component in a counter flow setup as mentioned above. A third liquid 418 can be introduced into the third channel 404 at a third predefined flow condition such that the third liquid 418 combines with the combined liquid exiting from the end 408 at the second liquid contact zone 410 to form a second combined liquid. In this setup, at least one of the first liquid 414, the second liquid 416 or third liquid 418 includes a gelling type hydrocolloid.

Advantageously, this allows for further variations in the textural profiles as a third liquid component is introduced. Different ingredients and nutrients can also be added without them adversely affecting or complexing with each other. Figure 11 demonstrates an edible composite made using the extrusion components in tandem. The first liquid 414 includes the protein isolate which partially encapsulates the second liquid 416. The second liquid includes oil, which due to its non-miscible nature with water, forms globules. The third liquid 418 includes gelling type hydrocolloid (alginate) and surrounds the first and second liquid completely. In this case, an unpleasant taste (for example in the oil) can be masked.

The extrusion components can also be arranged in parallel or in an array. This would allow for multiple edible composites to be formed at the same time, thereby providing convenience and time savings. The outflow from the array can also be merged to form a sheet, thereby providing edible composites with a different morphology.

The combined liquid is subsequently solidified by a gelling agent, temperature or a combination thereof. This can occur downstream of, for example, 110 of Figure 1. A gelling bath can be used. For example, if alginate is used, a calcium salt can be used as a gelling agent to cross link the alginate polymers. The calcium salt can be delivered to the alginate through a calcium bath. Examples of calcium salts that can be used are calcium chloride and calcium sulphate. If gelatin, for example, is used, temperature can be controlled to induce gelation. In this regard, the temperature can be controlled from about 0°C to about 20 °C. Gelation by temperature can be provided in a form of a water bath with its temperature regulated.

The desired textural properties can be selected from the group consisting of hardness, cohesiveness, springiness, chewiness and resilience. Such properties can be determined using texture profile analysis (TPA). This double compression test determines the textural properties of foods, in which samples are compressed twice using a texture analyzer to provide insight into how samples behave when chewed.

Hardness is a measure of the maximum force that occurs during the first compression. In some embodiments, the hardness is from about 400 gram-force (gf) to about 2000 gf, or about 500 gf to about 1800 gf. In other embodiments, the hardness is about 1300 gf to about 1800 gf. The gram-force is equal to a mass of one gram multiplied by the standard acceleration due to gravity on Earth, which is defined as 9.8 meter per second.

Cohesiveness is how well the product withstands a second deformation relative to its resistance under the first deformation. Cohesiveness is calculated by dividing the area under the plot of the second compression to the area under the plot of the first compression. In some embodiments, the cohesiveness is from about 0.50 to about 0.80, or about 0.55 to about 0.75. In other embodiments, the cohesiveness is about 0.75 to about 1, or about 0.8 to about 0.9.

Springiness is how well a product physically springs back after it has been deformed during the first compression and has been allowed to wait for the target wait time between strokes. The springback is measured at the down-stroke of the second compression. Springiness is expressed as a ratio deformed height to the original height. For example, the distance of the height during the second compression can be divided by the original compression distance. In some embodiments, the springiness is from about 0.55 to about 0.95. In other embodiments, the springiness is about 0.7 to about 0.8.

Chewiness is calculated as a product of hardness, cohesiveness and springiness. In some embodiments, the chewiness is from about 300 gf to about 1200 gf. In other embodiments, the chewiness is about 700 gf to about 1100 gf.

Resilience is how well a product "fights to regain its original height" and is measured on the withdrawal of the first penetration, before the waiting period is started. Resilience can be measured with a single compression; however, the withdrawal speed must be the same as the compression speed. It is calculated by dividing the upstroke energy of the first compression by the downstroke energy of the first compression. In some embodiments, the resilience is from about 0.30 to about 0.60. In other embodiments, the resilience is about 0.4 to about 0.5.

An example of the textural properties using a co-flow setup with sodium alginate in the first liquid and soy protein isolate in the second liquid is shown in Figure 14. The sample size is in each run is 2.

The first flow condition and the second flow condition can be selected according to a mathematical model in which the first and second flow conditions are stimuli, and the one or more desired textural properties are responses (Figure 5). For example, if the stimuli are determined to be (a) the concentration of the component in the first liquid, (b) the concentration of the component in the second liquid, and (c) the relative mass ratio, the textural properties can be calculated using Equation 1 : z ₁ + z ₂ (a) + z ₃ (b) + z ₄ (c) + z (ab) + z ₆ (ac ) + z ₇ (bc ) + z ₈ (abc) = Textural Property Value

(Equation 1); wherein Zi-Zs are constants and are coefficients that represent the relationship between the stimuli and a single textural property. For example, each test would correspond to 1 combination of the 3 stimuli values and 5 textural properties. With 8 tests, a total of 8 combinations of the 3 stimuli and 5 textural properties is obtained. This provides 5 sets of 8 equations, which when solved, give 5 sets of Zi to Zs values.

In this forward design model, the stimuli is used to correlate with the textural responses. Alternatively, a reverse design model can be employed in which the ideal textural response can be used as an input and through the modelled relationship, the closest response can be determined from which a set of flow conditions is recommended. This provides convenience to a user who chooses textural responses based on his preference and a set of input factors can be generated without much contribution from the user.

A program can be written to perform forward design and reverse design. For example, MATLAB can be used. In forward design, feeding the stimuli values will result in an output of response values, based on the linear mathematical model predictions. In reverse design, feeding the response values will result in the output/recommendation of design factors values, which will most closely mimic the input ideal response values. This can be achieved using both the mathematical model (Equation 1) and an algorithm that finds the design factors for best mimicry.

The program can be used to find the stimuli factors for best mimicry by solving an error minimisation problem. This is represented by Equation 2:

(Equation 2) wherein the ideal textural values are represented by Pi to P5. The actual textural values based on a particular combination of stimuli are represented by Ai to A5. The error at a particular combination of stimuli can be calculated and minimised, which would represent the best mimicry of textural properties of the edible composite.

Figure 15 illustrates the results in the forward design model, in which (a) is 10, (b) is 1.4 and (c) is 67.5.

Figure 16 illustrates results in the reverse design model. With the output textural properties, the proposed stimuli values are (a) 11, (b) 1.5 and (c) 55.

The present invention also relates to a device for forming an edible composite, comprising :

at least one processor in communication with machine-readable storage;

at least one extrusion component having a first channel and a second channel, an end of the second channel extending at least partly into the first channel, the at least one extrusion component having a liquid contact zone that is adjacent to the end of the second channel; and

at least one pump in communication with the at least one processor;

wherein the machine-readable storage has stored thereon machine-readable instructions which, when executed by the at least one processor, cause the at least one pump to:

pump a first liquid into the first channel at a first predetermined flow condition; pump a second liquid into the first channel or the second channel at a second predetermined flow condition, such that the second liquid combines with the first liquid at the liquid contact zone to form a combined flow; and

pump the combined flow to a solidification component to solidify the combined flow to thereby form the edible composite.

Advantageously, the device allows for an on-demand means to form edible composites. Instead of packaging and storing the edible composite, the edible composite can be formed as and when needed. This overcomes the problem of shelf-life. Further, a consumer can explore a range of textures and ingredients to create an edible composite that matches his preferences, thereby allowing for personalised nutrition.

For example, as shown in Figure 17, a device 1700 for forming an edible composite comprises at least one processor 1702 that is in communication with machine-readable storage 1704. In the example of Figure 17, a single processor 1702 is shown, but it will be appreciated that the device may include multiple such processors. The machine- readable storage 1704 may be a solid-state drive, or other type of non-volatile memory device capable of storing program instructions for execution by processor 1702, and data for use during execution of the program instructions.

For example, the memory 1704 in the embodiment shown in Figure 17 stores texture data 1730, corresponding to different values of the parameters of the first and second flow conditions of the method described above. The different values correspond to different desired textural property values of the extruded edible product. In some embodiments, the device 1700 may include a user interface 1710 that enables a user to select amongst predefined combinations of parameter values that provide particular textural properties.

The memory 1704 also stores a flow module 1740 that may read the texture data 1730, and control various components of the device 100 in accordance with parameters of the texture data 1730 to produce an extruded edible composite.

The device 1700 includes at least one extrusion component having a first channel and a second channel, an end of the second channel extending at least partly into the first channel, the at least one extrusion component having a liquid contact zone that is adjacent to the end of the second channel. For example, the at least one extrusion component can be in accordance with any one or more of the extrusion components 100, 200, 300, 400 shown in Figures 1-4.

The device 1700 also includes at least one pump in communication with the at least one processor 1702. For example, the device 1700 may include a first pump 1706 that is in fluid communication with a first liquid reservoir 1716, and a second pump 1708 that is in fluid communication 1718. The first pump 1706 may be connected to the first channel 102 of extrusion component 100, and the second pump 1708 may be connected to the second channel 104 of extrusion component 100.

The program instructions of flow module 1740 may cause the processor 1702 to instruct the first pump 1706 to pump, from the first reservoir 1716, a first liquid into the first channel 102 of the extrusion component 100 at a first predetermined flow condition. The first predetermined flow condition may be, for example, a concentration in the first liquid, as determined from the parameters in texture data 1730. The program instructions of flow module 1740 may also cause the processor 1702 to instruct the second pump 1708 to pump, from the second reservoir 1718, a second liquid into the second channel 104 of the extrusion component 100 at a second predetermined flow condition. The second predetermined flow condition may be, for example, a concentration in the second liquid, as determined from the parameters in texture data 1730.

As discussed above, the introduction of the first and second liquids into the extrusion component 100 results in the two liquids combining at a liquid contact zone to form a combined flow 1760. The program instructions of flow module 1740 may instruct the first pump 1706 and/or the second pump 1708 to pump the combined flow 1760 to a solidification component 1750. The solidification component 1750 may be a gelling bath, for example. The introduction of the combined flow 1760 to the solidification component 1750 causes the combined flow 1760 to solidify, thereby forming the edible composite.

The present invention also relates to an extruded edible composite, comprising :

a) an outer component; and

b) an inner component, the inner component adjacent to the outer component; wherein the outer component envelops the inner component;

wherein the inner component is selected from the group consisting of protein, oil, dietary supplement, food additive, vitamin, mineral, herb and dairy product, and

wherein the outer component is a gelling type hydrocolloid.

The extruded edible composite does not consist of a carbohydrate. For example, flour is not used.

The extruded edible composite can have an interface between the outer component and the inner component which is irregular. This is attributed to mixing as mentioned above.

The outer component can have a thickness of at least 10 pm. This ensures that the inner component is retained within the extruded edible composite. In this way, the inner component is not leaked out. The extruded edible composite can have a thickness of about 100 pm to about 10 mm.

Figure 6 and 7 illustrates edible composites extruded using a co-flow setup such as that shown in Figure 2. Two distinct phases can be observed, which is attributed to the laminar flow the first and second liquid.

Figure 10 and 11 illustrates edible composites extruded using a counter-flow setup such as that shown in Figure 3. This is a result of mixing by diffusion and instability. Figure 10 shows an edible composite in which the mixing is incomplete. When mixing is almost complete, a homogenous edible composite can be obtained as is shown in Figure 11.

The extruded edible composite can further include another inner component, the another inner component adjacent to the outer component. Similar to the inner component, the outer component envelops the another inner component, and specifically completely envelops the inner and another inner components. For example, the inner component can be a protein in an aqueous phase, and the another inner component can be an oil. In this regard, by controlling the flow conditions such that the volume of the inner component greater than the volume of the another inner component, oil form globules in the aqueous phase due to phase separation. This phase separation can be 'fixed' when it is extruded and solidified as the edible composite.

Figure 12 and 13 illustrates edible composites extruded using the tandem extrusion components such as that shown in Figure 4. By incorporating an additional component, another inner component can be formed, and accordingly the textural property of the edible composite can be varied.

Figure 8 and 9 illustrate edible composites with other textural properties. For example, a wavy second inner component can be obtained by introducing a kink (necking) or by controlling the mixing in the flow (Figure 8). By further controlling the temperature of the second liquid, a different inner morphology can be obtained. For example, as shown in Figure 9, by lowering the temperature of the second liquid, a 'lumpy' inner morphology is instead obtained. To show the applicability of the present invention, the method of forming edible composites was scaled up using the embodiment as shown in Figure 2. In this embodiment, the flow rates were increased to about 4200 pL/min for the first liquid and 700 pL/min for the second liquid, from 300 pL/min for the first liquid and 50 pL/min for the second liquid. The first liquid comprises 2% w/v sodium alginate and the second liquid comprises 12% w/v soy protein isolate.

Table 1: Comparison of edible composites under different flow conditions

Table 1 shows the results obtained. All mean values of the measured textural properties (Hardness, Cohesiveness, Springiness, Chewiness, Resilience) of the edible composites deviated by less than 10% from that of the original flow rates. This shows that when the flow rates are changed, good reproducibility can still be obtained if the relative flow rates remained the same.

The shelf life of the edible composites were also investigated. The stability of the textures of co-flowed edible composites stored in the fridge at about 3 °C over 16 days was determined. Texture Profile Analysis (TPA) were done on the edible composites throughout this period. All textural properties were found to be stable throughout the 16 days as illustrated in Figures 19 and 20.

The Coefficient of Variations (CVs) of the Mean values of each textural property were calculated over Day 0 to 16 and over Day 2 to 16 (Table 2). Using 5% Coefficient of Variation (CV) as the benchmark, the CV of the Mean values of all respective textural properties from day 2 to 16 are below this benchmark. Even with the inclusion of Day 0 Mean values for calculations, the CVs are all below 10%. This shows that the edible composites are stable over a period of at least 16 days.

Table 2: Coefficient of Variations of textural property means of edible composites

The health benefits of the edible composites on human subjects were investigated. Twelve subjects were given the edible composites with 250 mL of water to be consumed at an even pace within 12 to 15 minutes. As a control, 25 g of available carbohydrates was served (mee sua, a wheat flour noodle). Edible composites with weight equivalent to 25 g available carbohydrates of mee sua was served. Both co-flow and counter-flow produced edible composites as shown in Figures 2 and 3 were tested. Blood samples for glucose and insulin were subsequently collected at T= 15, 30, 45, 60, 90 and 120 minutes while blood samples for gut hormones were collected at subsequent timing at T=30, 60, 90 and 120 minutes. Subjective satiety levels were recorded by subjects by answering questions at every 30 min mark on a 100 mm visual analogue scale. Subjects were also asked to provide sensory evaluation of the microfluidic noodles. Figure 21 illustrates the plasma glucose change over time. Glycemic responses are shown after ingestion of 25 g dextrose (comparator), mee sua (control), co-flow edible composite and counterflow edible composite. Figure 22 shows the mean postprandial incremental area under curve (iAUC) of glucose responses. All data are presented in mean and 95% Cl, n = 12. The results show that edible composites of the present invention have negligible postprandial glycemic response.

Figure 23 presents the overall sensory evaluation of edible composites of the 12 subjects. In general, the edible composites were deemed to be palatable. Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates. Those skilled in the art will appreciate that the invention described herein in susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications which fall within the spirit and scope. The invention also includes all of the steps, features, combinations and compositions referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features.