Enclosing materials in natural transport systems
09795990 · 2017-10-24
Assignee
Inventors
Cpc classification
A23P20/15
HUMAN NECESSITIES
A23P20/20
HUMAN NECESSITIES
B05D2401/20
PERFORMING OPERATIONS; TRANSPORTING
A23L29/256
HUMAN NECESSITIES
A23P20/25
HUMAN NECESSITIES
A23P20/105
HUMAN NECESSITIES
B05D2350/60
PERFORMING OPERATIONS; TRANSPORTING
A23P10/30
HUMAN NECESSITIES
Y02W90/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
A23L2/00
HUMAN NECESSITIES
A23P20/20
HUMAN NECESSITIES
A23P20/10
HUMAN NECESSITIES
A23P10/30
HUMAN NECESSITIES
A23P20/15
HUMAN NECESSITIES
B05D3/00
PERFORMING OPERATIONS; TRANSPORTING
A61K9/00
HUMAN NECESSITIES
A23L29/256
HUMAN NECESSITIES
Abstract
Edible or potable substances can be transported in biodegradable vessel.
Claims
1. A system for storage and delivery of a potable substance, the system comprising: a potable substance; a manufactured inner membrane encapsulating the potable substance, and wherein the manufactured inner membrane comprises a polysaccharide polymer and/or an edible wax and is at least partially impermeable to the potable substance; and a manufactured outer shell encapsulating the manufactured inner membrane, wherein the manufactured outer shell is more impermeable and/or has higher strength and/or is more stable than the manufactured inner membrane, wherein the manufactured inner membrane is in contact with the manufactured outer shell.
2. The system of claim 1, wherein the polysaccharide polymer is selected from the group comprising an alginate and a gellan gum.
3. The system of claim 1, wherein the manufactured inner membrane comprises edible particles and a charged polymer charge cross-linked by multivalent cations, including cross-linking interactions between particles and alginates via bridges formed by the multivalent cations.
4. The system of claim 1, wherein the manufactured outer shell is biodegradable and/or edible.
5. The system of claim 1, wherein the manufactured outer shell comprises crosslinked copolymer.
6. The system of claim 1, wherein the manufactured outer shell comprises polylactic acid.
7. The system of claim 1, wherein the potable substance comprises a liquid selected from the group consisting of water, alcohol, juice, a carbonated beverage, and combinations thereof.
8. The system of claim 1, wherein the potable substance is at least one of a gel, an emulsion, and a foam.
9. A method comprising: coating a cooled potable substance in a manufactured inner membrane that is at least partially impermeable to the potable substance when at room temperature, wherein said inner membrane encapsulates the potable substance, and comprises a polysaccharide polymer and/or an edible wax; and coating the first inner membrane in a manufactured outer shell that is structurally stable at room temperature, wherein the manufactured outer shell encapsulates the manufactured inner membrane, and is more impermeable and/or has higher strength and/or is more stable than the manufactured inner membrane; wherein the manufactured inner membrane is in contact with the manufactured outer shell.
10. The method of claim 9, further comprising cooling the potable substance to a temperature below about 0 degrees centigrade.
11. The method of claim 9, wherein cooling the potable substance comprises cooling the potable substance in liquid nitrogen, particularly wherein the cooling of the potable substance comprises freezing the potable liquid into a mold before applying liquid nitrogen to the frozen liquid.
12. The method of claim 9, wherein coating the cooled potable substance in the manufactured inner membrane comprises coating with a polysaccharide polymer.
13. The method of claim 9, wherein coating the cooled potable substance in the manufactured inner membrane in a manufactured outer shell that is structurally stable at room temperature comprises coating with at least one of a calcium layer and a cross-linked polymer layer.
14. A system of a potable substance within a module for storage and delivery of the potable substance, the system comprising: a potable substance; a manufactured inner membrane at least partially impermeable to the potable substance, the inner membrane encapsulating the potable substance; and a manufactured outer shell having different properties than the manufactured inner membrane, the manufactured outer shell encapsulating the manufactured inner membrane, wherein the manufactured inner membrane and manufactured outer shell are biodegradable and/or edible, wherein the manufactured inner membrane comprises a polysaccharide polymer and/or an edible wax, and is in contact with the manufactured outer shell.
15. The system of claim 14, wherein the polysaccharide polymer is selected from the group comprising an alginate and a gellan gum.
16. The system of claim 14, wherein the manufactured inner membrane comprises edible particles and a charged polymer charge cross-linked by multivalent cations, including cross-linking interactions between particles and alginates via bridges formed by the multivalent cations.
17. The system of claim 14, wherein the manufactured outer shell comprises crosslinked copolymer.
18. The system of claim 14, wherein the manufactured outer shell comprises polylactic acid.
19. The system of claim 14, wherein the potable substance comprises a liquid selected from the group consisting of water, alcohol, juice, a carbonated beverage, and combinations thereof.
20. The system of claim 14, wherein the potable substance is at least one of a gel, an emulsion, and a foam.
Description
DESCRIPTION OF DRAWINGS
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(29) Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
(30) Embodiments of our liquid transport system can have, e.g., varying shell or membrane thickness, chemistry, varying numbers of shells or membranes, multiple internal content materials, various shapes, various shell/membrane properties including taste and resistance. These and other embodiments of these vessels can be made at large scale, including with injection, spray drying, fluidized bed and other technologies.
(31) Referring to
(32) Alginates are used in various applications, such as pharmaceutical preparations, impression-making materials (e.g., in dentistry and in prosthetics manufacturing), and in the food industry. Beyond their capability to easily form a gel, and their biocompatibility, alginates are also used for cell immobilization and encapsulation. Indeed, Na.sup.+ can be removed and replaced by divalent cation (e.g., Ca.sup.2+ or another multi-valent cation such as Mg.sup.2+), inducing a more rapid gelation by electrostatic cross-linking (see
(33) Thus, in recent years, sodium alginates have found application in restaurants, e.g., to create spheres of liquid surrounded by a thin jelly membrane. Chefs such as Ferran Adria use this technique today to create “melon caviar,” “false fish eggs” etc. by adding sodium alginates into a liquid (e.g., melon juice), then dropping the preparation in a calcium bath (calcium lactate or calcium chloride). Two parameters remain difficult to optimize or control: (i) the size of the spheres; and (ii) the texture of the liquid embedded in the membrane. The size of the spheres is problematic since, in known methods, the liquid falls in the calcium bath from a syringe or a straw, limiting the size of the sphere. Making a “giant” sphere is, so far, with current technology, a prohibitive challenge due to gravity forces ultimately overwhelming surface tension forces. In terms of texture, alginates can strongly increase the viscosity of the liquid. The increased viscosity can be required to stabilize and to form the jelly membrane more easily. However, the increased viscosity is not always pleasant while tasting and/or consuming the liquid, and the increased viscosity can mask aromas of the liquid.
(34) Our approach involves a new kind of encapsulated vessel that uses existing and new materials to provide macroscopic vessels for material transport with the properties of strength, stability, and biodegradability necessary to transport water and other materials as we presently and historically transport water and other materials in bottles, buckets, glasses and other classical vessels. We have performed initial experiments to reduce our concept to practice.
Example 1—Preparation of a Stable and Mechanically Robust Alginate Shell for Liquid Encapsulation
(35) As shown in
(36) The exemplary process included the following steps:
(37) (a) The liquid is frozen in the desired form
(38) (b) The solid form is then further cooled in liquid nitrogen.
(39) (c) The solid from step (b) is placed in sodium alginate solution. As the solid is very cold, alginates freeze on the surface. Thus, the thickness of the final jelly membrane is readily tunable.
(40) Moreover, nitrogen liquid induces a “dried and cold” surface after the step (b), which is the reason alginates adhere easily on this surface. Through our experiments, we have discovered that the step (b) provides particularly improved results: in the case of the process of step (a) directly to step (c) (skipping step (b)), the solid in contact with the alginate solution at room temperature (approximately 20° C.) melts quickly on the solid surface, thus creating a liquid film between the solid and the alginate solution. Consequently, it is very difficult to stabilize a homogeneous membrane.
(41) (d) After the desired time needed to achieve the desired thickness of the membrane, the membrane-covered solid is placed in calcium solution (e.g., calcium chloride solution), where gelation occurs.
(42) After this step, it is possible, alternately, to place the calcium-coated solid in alginates, and then once again, to place the membrane-covered solid in calcium, step (c) to step (d), etc. Repeating this process produces a much thicker, harder, and more rigid shell.
(43) (e) The membrane covered frozen solid is rinsed in water. The liquid within the calcium-coated membrane is allowed to melt gradually.
Example 2—Protective Effects of Inner Membrane
(44) To demonstrate that a hard, external, biodegradable membrane can be protected from the water that it contains by the soft internal membrane, e.g. produced by calcium alginate, we produced outer shells of polylactic acid (PLA) and exposed them to either water or to water with a membrane of calcium alginate between the water and the PLA. We exposed the PLA shells, with and without the calcium alginate membranes, to 45 degrees C. external temperatures for 30 days and then observed the PLA shells afterward.
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Example 3—Protective Effects of Outer Shell
(47) To show that the outer rigid membrane furthermore protects the inner (e.g. calcium alginate) membrane from leakage and instability, we prepared alginate bottles with orange juice and placed these spherical containers of liquid either on a plate and napkin at −4 C or inside a hard polymeric shell formed of PLA. In some instances, other material can be used to form such shells.
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(49) The series of figures show that the spherical alginate bottles deform over time and lose volume due to diffusion through the membrane and evaporation whereas the spherical alginate bottles in the polymeric shells do not lose shape or volume. This, in addition to the physical protection offered by the polymeric shells, reveals that, while the alginate membranes protect the PLA biodegradable shells from water damage (
Example 4—Formation of a Rigid External Alginate Shell
(50) In an alternate approach, chemically modified alginates were used to produce a rugged external membrane in place of the PLA outer shell. This approach provided the key advantages of long-term strength and stability by chemically cross linking the macroscopic shell with intermolecular covalent bonds in order to improve the mechanical properties.
(51) Methacrylation of Alginate
(52) Photocrosslinkable alginate macromers were prepared by reacting sodium alginate and 2-aminoethyl methacrylate in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride and N-hydroxysuccinimide.
(53) Experimental Protocol: The methacrylated alginate was prepared by reacting high molecular weight alginate (˜300,000 g/mol) with 2-aminoethyl methacrylate (AEMA, Sigma). Methacrylated alginate with 50% theoretical methacrylation of uronic acid carboxylate groups was synthesized by dissolving high molecular weight sodium alginate (1 g) in a buffer solution (1% w/v, pH 6.5) of 50 mM 2-morpholinoethanesulfonic acid (MES, Sigma) containing 0.5 M NaCl. The N-hydroxysuccinimide (NHS, 1.3 g; Sigma) and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC, 2.8 g; Sigma) (molar ratio of NHS:EDC=1:1.3) were added to the mixture to activate the carboxylic acid groups of the alginate. After 5 minutes, AEMA (2.24 g) (molar ratio of NHS:EDC:AEMA=1:1.3:1.2) was added to the product and the reaction was maintained at room temperature for 4 days. The mixture was precipitated with the addition of excess of acetone, dried under reduced pressure, and rehydrated to a 1% w/v solution in ultrapure deionized water (diH2O) for further purification. The methacrylated alginate was purified by dialysis against diH2O (MWCO 3500) for 3 days, filtered (0.22 mm filter), and lyophilized.
(54) Preparation of a Calcium Alginate Hydrogel Shell
(55) Spherical shaped frozen liquids were coated with a calcium alginate hydrogel shell. Frozen liquids were first coated with an aqueous solution of CaCl.sub.2 before being exposed to 1% MA-alginate solution containing 0.1% photo initiator. Here again, this process can be repeated several times until the desired thickness of shell is reached. Immediately upon contact with CaCl.sub.2, the MA-alginate solution absorbs calcium ions, which causes solidification of the entire shell suspension, resulting in a shape-retaining, spherical liquid container. The spherical container can then be rinsed several times in water to remove excess of MA-alginate and CaCl.sub.2.
(56) Final Process
(57) Photocrosslinked and biodegradable alginate was engineered to further stabilize the shell formed by the calcium alginate hydrogel. Methacrylated alginate, which is the main component of the shell, was photocrosslinked by exposure to ultraviolet light for 20 minutes. The resulting modification serves to stabilize the shell morphology, thus reducing or eliminating deformation or destruction of the spherically-shaped macrocapsule.
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(59) Initial preliminary tests based on the process summarized in
(60) 11(a) shows MA-alginate+photoinitiator; photo-treatment with ultraviolet light for 20 min;
(61) 11(b) shows MA-Alginate+photoinitator; coated with an aqueous solution of CaCl.sub.2;
(62) 11(c) shows MA-Alginate+photoinitator; coated with an aqueous solution of CaCl.sub.2; rinsed twice in water to remove excess CaCl.sub.2; photo-treatment with ultraviolet light for 20 min; and
(63) 11(d): MA-Alginate+photoinitator; frozen in liquid nitrogen in cylindrical shape; coated with an aqueous solution of CaCl.sub.2; rinsed twice in water to remove excess CaCl.sub.2; photo-treatment with ultraviolet light for 20 min.
(64) After UV-treatment, we obtained a solid membrane in cases (a), (c) and (d). These results indicate that a photocrosslinked alginate membrane can be successfully obtained through the described process described. A slight change of color of samples (a) (c) and (d) can be observed in comparison with the sample (b). This likely indicates that a chemical reaction occurs. The addition of CaCl.sub.2 does not alter the results of the U.V. treatment. Freezing of MA-alginate and photoinitiator does not alter the results of the U.V. treatment. Freezing of MA-alginate and photoinitiator allows the preservation of specific shapes.
(65) Initial observations indicate that sample (c) and (d) present the more solid mechanical membrane (in comparison with (a) and (b)). Mechanical physical measurements are underway to confirm this point.
Example 5—Preparation of a Stable and Mechanically Robust Gellam Gum for Liquid Encapsulation
(66) In one embodiment, we prepared a liquid transport and storage container with gellan gum modified by a calcium external shell. Gellan gum is also a polysaccharide, consisting of two residues of D-glucose and one of each residues of L-rhamnose and D-glucuronic acid. Gellan gum is produced by the bacterium Sphingomonas elodea. This polysaccharide is also considered a promising candidate, since (i) it is also a water-soluble polysaccharide and easy to use; (ii) the sol-gel transition occurs by heating/cooling thermal treatment (physical gelation) without using a chemical agent (such Ca.sup.2+). Consequently, the process to form the initial volume is simpler than the step (d) in
(67) We have realized a sphere (8 cm diameter) composed with gellan gum membrane by two processes. The first process consists of placing the frozen liquid in a gellan gum hot solution. As the surface of the solid is cold, the gelation occurs suddenly. We can use liquid nitrogen to increase the thickness of the membrane. The solid volume is then extracted from the gellan solution. The solid melts slowly into a liquid, which is then embedded in a gellan membrane.
(68) The second process produces a smoother external surface, as follows (see
(69) (a) Gellan gum is dissolved in boiling water. A high concentration (>4% in mass) is required to get a robust membrane, which must compensate the weight of a high volume of liquid.
(70) (b) While the gellan gum solution is still hot (i.e. T>T.sub.gel), the liquid is introduced into a mould. (In our example, the mold has the form of two half spheres, which are then linked). This technique allows angles, and thus design of complex volumetric shapes.
(71) (c) The temperature is decreased to below T.sub.gel. The mold is removed. At the end of this step, we obtain a solid volume, empty (hollow) inside.
(72) (d) The liquid (water for example) can be injected into the volume.
(73) (e) The hole (caused by the syringe) is closed by using a hot (T>T.sub.gel) needle.
(74) From a culinary point of view, this process allows chefs to create a cocktail (cold or hot) wherein the glass (volume container) can be completely edible (and an integral part of the cocktail). Of course, it can be extrapolated towards many preparations, and this process can be extended to different fields of applications.
(75) The next step is to chemically-modify the gellan gum to produce a rugged external surface (as done with the alginates in the example above). While it is possible to chemically modify gellan gum by methacrylation (as we did with alginate), and to photo polymerize the membrane, we chose here to reinforce the membrane by an in-situ crystallization in the gel. In this case, we immersed our gellan sphere in a concentrated carbonate solution (Na.sub.2CO.sub.3) and convected (e.g., heated) the solution past the sphere. Then, we immersed the gellan sphere in calcium solution (CaCl.sub.2) and convected the solution again. In the gel, the crystallization of calcium carbonate occurs quickly: Ca.sup.2++CO.sub.3.sup.2.fwdarw.CaCO.sub.3 (K=4×10.sup.9). This process allows us to build up a solid membrane of calcium carbonate as with an egg shell (i.e. particles of calcium carbonate particles are embedded in the gellan gel matrix). The external membrane becomes hard and resistive and can be made particularly thick with long convection (heating) exposure time of the calcium carbonate solution. The concentration of CO.sub.3.sup.2− and Ca.sup.2+ in solutions and time of immersion in batches are parameters to be controlled to obtain a rigid and inert membrane as in an egg shell.
Example 6—Food Particle-Containing Alginate Shells
(76) The membrane can be designed to be stronger, thinner/thicker, or taste in a particular way, by adding suspended particles of food, e.g. chocolate, nuts, caramel, orange rind, or other particles at least partially insoluble in water. The particles can be sized (e.g., chosen or formed) such that the maximum dimension of the container formed by the membrane is about 50 or 100 times larger (or more) than the maximum dimension of the particles.
(77) Often these particles will be charged (i.e. most particle surfaces have some charge or zeta potential). This charge can be modified by the way each particle is created, its size, and the nature of the particle surface. Surfactants can be added to enhance the charged nature and the ionic atmosphere of the water can also be modified beneficially. When in alginate, or aqueous medium, these particles (assuming they are zwitter ionic or oppositely charged to the membrane forming material, such as the alginate) will undergo strong or weak associations with alginate but not so strong as to cause gel formation. When in contact with calcium, for example, particles will form with alginate a gelled membrane through interaction of the calcium and food particles trapped within the membrane, possibly strengthening it, improving flavor, etc.
(78) These same methods can be extended to any kinds of small particles with a charge, thus creating a new class of membrane, formed by a charged polymer, such as alginate, and charged particles, with or without the addition of a multivalent cation such as calcium.
(79) Chocolate-Containing Alginate Shells
(80) We demonstrated this concept by lowering the alginate concentration in water to 1.8% by weight and formed orange juice containers with membranes made with high, medium, and low concentrations of chocolate particles between about 0.1 and 5% chocolate particles by weight. The resulting membranes are shown in
(81) Almond-Containing Alginate Shells
(82) We also demonstrated this concept by forming containers with membranes made with alginate solutions with 6.4% food particles. The food particles included almond powder and, in some instances, various fruit powders. The almond powder had particles on the order of tens and hundreds of microns and was purchased retail in this form from the Vahiné food company in France. We formed containers with membranes made with alginate solutions with 6.4% food particles by dissolving/mixing 6.4 g ground almond powder into 100 g of an alginate solution (1.8% alginate). The alginate solution with almond powder produced a relatively opaque fluid (milky/creamy color), and maintains the fluidity of the original sodium alginate solution over time (at least 3-5 days). The almond combination seems to color and make fluid surrounding individual almond particles more opaque or at least translucent. In contrast, in the “sodium alginate solution+chocolate particles” membrane discussed above with respect to
(83) We also formed containers with membranes made with alginate solutions with 6.4% food particles by dissolving 6.4 g ground coconut powder into 100 g of an alginate solution (1.8% alginate). The coconut pieces had small, generally crescent-like shapes with characteristic size on the order of hundreds of microns or several (1-3 or more) millimeters. The powder was purchased from Vahiné in France. The alginate solution with coconut powder maintains the fluidity of the original sodium alginate solution over time (at least 3-5 days). This mixture did not visibly have the effect of increasing overall opacity (beyond line-of-sight opacity of the coconut particles themselves) as seen in the almond mixture. By placing a high proportion of coconut powder into the alginate solution, opacity could be increased. Beyond a certain proportion of coconut particles in the mixture, however, the membrane ultimately was found to be more permeable when in container form, and at higher risk of leaking Particle size and shape may play an important role in the transparency, in particular as compared to the almond powder example noted above, since the coconut particles used were generally larger. There was little or no visible dissolution of coconut particles in the solution. It was also noted that when left to sit, the mixture of coconut pieces and alginate solution did not result in a substantial proportion of coconut pieces settling to the bottom. Such settling was found to be the case with many other food particles tested with alginate solution. The taste of the coconut membrane was found to relatively strong.
(84) We also formed containers with membranes made with alginate solutions with 6.4% food particles by dissolving 4.0 g ground almond powder and 2.4 g ground lyophilized mango powder into 100 g of an alginate solution (1.8% alginate). This solution remained fluid for a certain time, but we noted that the fluidity had decreased considerably within roughly 50 hours. As such, we could still add additional mango powder to increase the fruit flavor, without losing too much fluidity. This mixture did not have the effect of increasing overall opacity as seen in the almond mixture. Particle size and shape may play an important role in the transparency, in particular as compared to the almond powder example noted above, as the mango particles used were larger, ranging from hundreds of microns to several millimeters, and had various non-uniform shapes.
(85) We also formed containers with membranes made with alginate solutions with 6.4% food particles by dissolving 6.0 g ground almond powder and 0.4 g ground lyophilized raspberry powder into 100 g of an alginate solution (1.8% alginate). This combination produced a fluid that solidified relatively quickly (faster than the mango example), i.e. within a few (1-4) hours. It was noted that to a certain extent the (red) color of the raspberry spread throughout the fluid, making it translucent, even where solid raspberry particles were not present.
(86) We also formed containers with membranes made with alginate solutions with 6.4% food particles by dissolving 6.0 g ground almond powder and 0.4 g ground lyophilized blackcurrant powder into 100 g of an alginate solution (1.8% alginate). This combination produced a fluid that solidified into a relatively hard gel fastest: 10 minutes to an hour. The fruit also somewhat colored the overall fluid to make it translucent.
(87) Mixing dried fruit powders with the alginate solution, in particular raspberry and blackcurrant powders, produced relatively rapid “gelification”, or a hardening of the fluid into a more solid gel. It is hypothesized that a property of the fruits tried or a substance contained within them, such as acidity/acids, plays a role in this gelification process, perhaps in effect replacing the cations provided by, for example, calcium chloride solution in other examples noted separately. It appears that blackcurrant is a more rapid “gelling agent” than raspberry, perhaps owing to greater acidity. It is possible that this gelling process obviates the need for other gelling components/steps such as with calcium chloride as described elsewhere.
(88) These observations suggest that, in order to have a membrane with substantial fruit (e.g. raspberry or blackcurrant) flavor, it is sometimes useful to use many small aggregated “chunks” or “chips” of fruit powder, rather than a homogeneous mixture of alginate solution and fruit powder, to create individual, point-like flavorful fruit pieces within the membrane. In the mango example, slower hardening/gelification allowed for a greater amount of mango powder to be added, to enhance taste, without an immediate loss of fluidity. The chocolate particles used in other examples resulted in a less strongly flavored solution/membrane than many of the fruit combinations described here.
(89) The relatively high opacity produced by the almond powder membrane, and the translucence/semi-opacity produced in other sample membranes, can be useful for aesthetic and/or culinary purposes. The size and shape of the particles in the various powders used likely plays an important role in the opacity/translucence of the solution. The almond powder, for example, was finer than previously used chocolate powders; this may help explain the increased opacity. The properties of the particles also likely play a role in the “strength” and/or permeability of the eventual container.
(90) Food Particle Shells Containing Some Alginate
(91) Natural food particles often have natural negative surface charges. Thus, edible bottles can be made of membranes comprised primarily of natural food particles, which can be mixed with alginate solutions (also negatively charged). We demonstrated this by making edible bottles with the following membrane compositions:
(92) 1) 15 g sodium alginate/60 g chocolate particles (formed by grating Lindt and other fine chocolate bars into small particles)/1 L water
(93) 2) 15 g sodium alginate/60 g coconut particles/1 L water
(94) 3) 15 g sodium alginate/60 g dried fruit (lemon, orange, cherry) particles/1 L water
(95) We also made similar membranes with smaller quantities of particles (5, 10, 15, 30 g) and greater quantities of particles (120 g) too.
(96) We froze orange juice and other juices into ice cubes (“cube” defined in the general sense of any form reminiscent of an “ice cube” regardless of actual shape) and dropped these into liquid nitrogen for 15-30 seconds. We removed the ice cubes from the liquid nitrogen and placed the ice cubes in one of the solutions listed above for 15-30 seconds after which we removed the alginate/particle-coated ice cubes and placed them in solutions of 1.5% calcium chloride or magnesium chloride for 20 seconds-1 minute. After removing the ice cubes from the calcium or magnesium chloride solutions, we dropped them in a bath of water to rinse and then removed to allow the “edible bottles” to thaw completely. The results were orange juice (and other juices) contained within membranes of chocolate, coconut, and fruit particles integrated into the calcium-alginate membrane. These membranes proved relatively tasty and capable of preventing liquid from leaking from the bottle even when handled.
(97) The high concentration of particles in the membranes reflects a charge-charge interaction between the calcium and magnesium divalent cations and the food particles (as between the divalent cations and the alginates). The food particles became an integral part of the cross-linked membrane. In contrast to previous work in which food particles coat calcium alginate membranes, this approach actually integrated the food particles within the membrane and reduced the mass of alginate in the membranes while increasing natural-particle mass.
Example 7—System for Enclosing Fluids in a Natural Transport System
(98) Referring now to
(99) As also described in further detail below, during use, the fluid delivery apparatus 100 moves a combined flow of a first fluid and a second fluid into the reactor module 200a, where the first fluid hardens into a membrane substantially surrounding the second fluid to form a fluid container. The fluid container moves (e.g., under the force of gravity) through the outlet conduit 300a and into the reactor module 200b, where the fluid container is rinsed. The rinsed fluid container moves through outlet conduit 300b and may be collected for distribution and/or consumption.
(100) The first fluid and the second fluid may each include a liquid, a solution, a suspension, a colloid, and/or a gel. In certain embodiments, the first fluid is different from the second fluid. For example, the first fluid can include an alginate (e.g., sodium alginate) and the second fluid include water (e.g., pure water, fruit juice).
(101) Referring now to
(102) The first housing 102 has a first inlet portion 116 and a first outlet portion 118. A first tubing 110 is disposed along first the inlet portion 116 and in fluid communication with the first housing 102 such that the first fluid is introduced into the first housing 102 through the first tubing 110. In some embodiments, the first housing 102 is substantially cylindrical and has a diameter of about 5 mm to about 50 mm (e.g., about 20 mm to about 30 mm). In certain embodiments, the first housing 102 has a substantially uniform cross section from the first inlet portion 116 to the first outlet portion 118.
(103) The second housing 104 has a second inlet portion 120 and a second outlet portion 122. A second tubing 112 extends into the first housing 102 and into fluid communication with the second housing 104 such that the second fluid is introduced into the second housing 104 through the second tubing 112. In some embodiments, the second housing 104 is substantially cylindrical and has a diameter of about 10 mm to about 45 mm (e.g., about 15 mm to about 25 mm). The second outlet portion 122 of the second housing 104 includes a frustoconical section 124 and a tube 126. The decreased cross sectional area of the second housing 104 in the direction extending from the second inlet portion 120 to the second outlet portion 122 can, for example, increase the speed of the flow of the second fluid as it moves into the first fluid.
(104) In some embodiments, pressures driving the two fluids can be independently controlled, for example, to control independently the speed of the first fluid moving through the first housing 102 and the speed of the second fluid moving through the second housing 104. For example, the pressure driving the two fluids can be independently controlled by changing the speed of a respective pump in fluid communication with the first housing 102 and the second housing 104.
(105) In certain embodiments, the second outlet portion 122 defines an orifice 127 (e.g., a substantially circular orifice). In some embodiments, the surface tension forces on the second fluid at the orifice 127 are less than the gravitational forces on the second fluid when the second outlet portion 122 is pointed toward the ground.
(106) The second housing 104 is disposed within the first housing 102 such that the space (e.g., annulus) between the inner portion of the first housing 102 and the outer portion of the second housing 104 defines at least a portion of a first fluid passage 106 extending from the first inlet portion 116 to the first outlet portion 118. The second housing 104 also defines at least a portion of a second fluid passage 108 extending from the second inlet portion 120 to the second outlet portion 122. The second outlet portion 122 terminates within the first fluid passage 106 such that fluid exiting from the second outlet portion 122 is injected into the first fluid in the first fluid passage 106. For example, the tube 126 of the second outlet portion 122 can terminate about 0.5 mm to about 10 mm (e.g., about 2 mm) upstream of the first outlet portion 118. The flow controller 114 is disposed adjacent to the first outlet portion 118 and upstream of the reactor module 200a. As described in further detail below, the flow controller 114 includes at least one movable element that can move to interrupt (e.g., at least partially block and/or shear) the combined flow of the first and second fluid moving from the first outlet portion 118 and into the reactor module 200.
(107) Referring to
(108) The stationary element 136 defines a circular orifice 140 and is disposed toward the bottom portion 130 of the housing 128 such that the circular orifice 140 is adjacent to the first outlet portion 118 of the first housing 102. The stationary element 136 can be a disk having a diameter of about 3 cm to about 18 cm (e.g., about 9 cm). The planar surface of the disk may be oriented substantially perpendicular to the direction of flow of the combined first fluid and second fluid moving out of the first outlet portion 118.
(109) The rotatable element 138 defines a substantially kidney-shaped orifice 138 and is disposed toward the upper portion 129 of the housing 128 such that the rotatable element 138 is adjacent to the reactor module 200a during use. The rotatable element 138 and the stationary element 136 are arranged relative to one another such that at least a portion of the kidney-shaped orifice 138 aligns with at least a portion of the circular orifice 140 as the rotatable element 138 moves through 360 degrees of rotation. Such alignment of the kidney-shaped orifice and the circular orifice 140 can allow substantially unimpeded flow from the first outlet portion 118 to the reactor module 200a. When the kidney-shaped orifice 138 and the circular orifice 140 are not aligned, the combined first fluid and second fluid accumulates in the first outlet portion 118. Additionally or alternatively, the relative movement of the kidney-shaped orifice past the circular orifice 40 can create a shear force sufficient to separate (e.g., slice) a portion of the combined flow of the first fluid and the second fluid from the remainder of the combined flow moving through the first outlet portion 118.
(110) The movement of the kidney-shaped orifice 138 relative to the circular orifice 140 can be used to control the number of fluid containers created by the fluid enclosing system 10. For example, the actuator 132 can be a handle such that the movement of the kidney-shaped orifice 138 relative to the circular orifice 140 can be manually controlled. Additionally or alternatively, the actuator 132 can be a motor coupled to the rotatable element 134 such that the kidney-shaped orifice 138 moves past the orifice 140 at a substantially regular interval. The number of fluid containers created by the fluid enclosing system 10 can be controlled by controlling the motor speed.
(111) In certain embodiments, the rotatable element 138 is the same overall size as the stationary element 136 to facilitate, for example, alignment of the rotatable element 128 and the stationary element 136. In some embodiments, the rotatable element 134 and/or the stationary element 136 can be a disk having a diameter of about 3 cm to about 18 cm (e.g., about 9 cm). The planar surface of each disk may be oriented substantially perpendicular to the direction of flow of the combined first fluid and second fluid moving out of the first outlet portion 118.
(112) Referring now to
(113) A reactant source 208 is in fluid communication with the reservoir section 202 such that the reactant 201 from the reactant source 208 can be moved by a pump 207 into the reservoir section 202. The reactant source 208 can also be in fluid communication with the removal section 206 such that excess reactant (e.g., reactant that does not react with the first fluid of the fluid container 209) can be returned to the reactant source 208 to reduce, for example, the amount of reactant required to create fluid containers 209. The reactant 201 can be, for example, a calcium chloride (CaCl.sub.2) solution to facilitate hardening of the first fluid into a membrane substantially surrounding the second fluid.
(114) The fluid delivery apparatus 100 is disposed toward a side of the reservoir section 202 substantially opposite the transfer section 204 to facilitate exposure of the discrete volume of combined first fluid and second fluid to the reactant 201 over a time sufficient to allow the first fluid to form a substantially hardened membrane substantially enclosing the second fluid therein to form the fluid container 209. In some embodiments, the time from the introduction of the of the discrete volume of combined first fluid and second fluid to the time of transfer of the formed fluid container 209 is about 1 s to about 300 s, e.g., about 60 s.
(115) The fluid container 209 moves through the reactant 201 in a direction from the fluid delivery system 100 toward the transfer section 204. In some embodiments, this movement of the fluid container 209 due at least in part to the introduction (e.g., pumping) of reactant into the reservoir section 202, near the fluid delivery apparatus 100, such that a current is induced in the reactant 201 in the reservoir section 202. Additionally or alternatively, the fluid container 209 can be buoyant with respect to the reactant 201 such that air bubbles can be introduced into the reservoir section 202, near the fluid delivery apparatus 100, and the air bubbles carry the fluid container 209 toward the transfer section 204.
(116) Referring now to
(117) As the fluid container 209 moves from the reservoir section 202 toward the transfer section 204, the first lock 210 is removed from the flow path of the fluid container 209 such that the fluid container 209 may float on the reactant 201 and into the transfer section 204. With the fluid container 209 and the reactant 201 in the transfer section, the first lock 210 is moved to substantially separate the reservoir section 202 from the transfer section 204. The second lock 212 can be moved to allow the reactant 201 and the fluid container 209 to flow into and fill the removal section 206. The reactant 201 can reduce the forces imposed on the fluid container 209 as it moves from the transfer section 204 to the removal section 206. For example, the reactant 201 can act as a cushion as the fluid container 209 moves from a higher level in the transfer section 204 toward a lower level in the removal section 206.
(118) The removal section 206 defines a drain 214 toward a lower portion (e.g., the bottom surface) of the reactor module 200. In the removal section 206, the movement of the reactant 201 toward the drain 214 also moves the fluid container 209 toward the drain such that both the reactant 201 and the fluid container 209 move through the drain 214. The drain 214 is sized to be larger than the largest dimension of the fluid container 209 to reduce the likelihood that the fluid container 209 could become stuck in the drain 214. In some embodiments, the reactant 201 and the fluid container 209 move toward the drain 214 under the force of gravity and/or under the force of the flowing reactant 201.
(119) Referring again to
(120) The outlet conduit 300a includes a first connecting section 302 and a second connecting section 304 disposed at either end of a main section 306. The outlet conduit 300a can facilitate separation of the fluid container 209 from the reactant 201 with minimal transfer of fluid from the reactor module 200a to a downstream process (e.g., a process in reactor module 300b). Additionally or alternatively, the outlet conduit 300a can facilitate delivery of the fluid container 209 into a new medium with minimal damage to the fluid container 209.
(121) A channel 308 extends along the outlet conduit 300a from the first connecting section 302 to the second connecting section 304. The channel 308 can define one or more orifices (e.g., for fluid communication with the return line 215) sized to allow the reactant 201 to drain from the outlet conduit 300a before reaching the reactor module 200b but retaining the fluid container 209 in the outlet conduit 300a.
(122) When the outlet conduit 300a is mounted between the reactor module 200a and the reactor module 200b, the first connecting section 302 and the second connecting section 304 are each substantially vertically oriented. This vertical orientation can facilitate, for example, connection of the outlet conduit 300a to the reactor module 200a and the reactor module 200b. Additionally or alternatively, the return line 215 can be in fluid communication with the outlet conduit 300a at the end of the vertically oriented first connecting section 302 such that the reactant 201 moving through the outlet conduit 300a can move into the drain line 215 under the force of gravity. In some embodiments, multiple return lines 215 are in fluid communication with the outlet conduit 300a to facilitate removal of the reactant 201 prior to the reactor module 200b. Additionally or alternatively, the drain capacity of the outlet conduit 300a and/or the return line 215 is greater than or equal to the flow of reactant 201 passing through locks 210 and 212 and into the removal section 206. For example, the drain capacity of the outlet conduit 300a and/or the return line 215 can be greater than or equal to the volume of reactant 201 held between the first lock 210 and the second lock 212 during movement of the fluid container 209 through the reactor 200a.
(123) The second connecting section 304 can be coupled to a top portion of the reactor module 200b such that the fluid container 209 moving through the outlet conduit 300a can drop into the reservoir section 202 of the reactor module 200b. In some embodiments, the reservoir section 202 contains a volume of rinse fluid (e.g., water) to remove excess material from the fluid container 209. The fluid container 209 can move through the reactor module 200b in a manner analogous to that described above with respect to the reactor module 200a.
(124) For example, while the first housing 102 has been described as having a substantially uniform cross-section along its length, other embodiments are possible. Referring to
(125) As another example, referring to
(126) In some embodiments, the charge on an electrically polarized surface can be transferred to one or both of the first fluid and the second fluid. In certain embodiments, an alternating current can be used to electrically polarize a surface of the first housing 152 and/or the second housing 154. Alternating the current at a range of frequencies can increase the diffusion of the second fluid and/or increase diffusion of ions within the second fluid into the first fluid. Such increased diffusion can, for example, result in faster hardening/curing of a membrane thus, for example, reducing the residence time required to form the fluid bottle 209 in the reactor module 200a. Additionally or alternatively, the amplitude of the frequency oscillation can also be varied. Such variation in amplitude can, for example, be used to control the thickness of the membrane of the fluid container 209.
(127) As still another example, while second housing 154 has been described as including an electrically polarized surface, the first housing 152 may additionally or alternatively include an electrically polarized surface.
(128) As yet another example, while alternating current has been described as being applied to at least one of the first housing 152 and the second housing 154, other embodiments are possible. For example, an alternating current can be applied to a reactant disposed in the reactor module 200a.
(129) As yet another example, many of the physical and/or chemical properties that will define a fluid container made by a fluid enclosing system may depend on the ratio of various dimensions of a fluid delivery apparatus. Examples of physical and/or chemical properties that may depend on relative dimensions of the fluid delivery apparatus include: the ratio of the membrane thickness to the interior volume of the fluid container; uniformity of hardening and/or curing of the membrane; thickness of the hardened and/or cured portions of the membrane versus unhardened and/or uncured portions of the membrane; density or other physical properties that might facilitate shearing the combined flow of the first fluid and the second fluid through a flow controller; and diffusion of a reactant (e.g., calcium) which may impact the quality of the membrane of the fluid container and/or the quality of the liquid contained within the membrane.
(130) For example, referring to
(131) The second orifice 168 is set upstream of the first orifice 166 such that a second fluid can move through the second orifice 168 into a first fluid flowing in a first fluid passage 170 at least partially defined by the first housing 162. In some embodiments, a distance “c” between the first orifice 166 and the second orifice 168 is varied to change the physical and/or chemical properties of the fluid container.
(132) The second orifice 168 is arranged at a distance “b” from the first housing 162. In some embodiments, the distance “b” is varied to change the physical and/or chemical properties of the fluid container.
(133) As yet another example, while the flow controller 114 has been described as at least partially interrupting a substantially continuous flow of the combined first fluid and second fluid moving out of the top portion 130 of the housing 128, other embodiments are possible. For example, referring still to
Example 8—System for Enclosing Foods in a Natural Transport System
(134) We demonstrated a prototype mechanized process for producing the edible bottles based on the methodology described in the previous examples. As shown in
(135) The guide path 612 extended through two reservoirs 614, 616. The first reservoir 614 contained an alginate solution and the second reservoir 616 contained a calcium chloride solution as described in the previous examples. It is anticipated that some embodiments of the system will include more reservoirs and/or the reservoirs can be used to hold other solutions. For example, some systems can include a reservoir containing liquid nitrogen, and a reservoir containing alginate (possibly with food particles), a reservoir containing calcium chloride or magnesium chloride, a reservoir containing a coating wax, and/or a reservoir containing water for rinsing the coated cube.
(136) The prototype system 600 also included two conveyor belts (or track “chains”) 618, 620. Each reservoir is associated with a separate conveyor belt to limit cross-contamination between reservoirs. Systems with more reservoirs containing different solutions typically also include more conveyor belts. The conveyor belts 618, 620 in the prototype system 600 were operated by electric motors 622, 624 powered by 12 V batteries.
(137) In the prototype system 600, the movable cars 610 were two-piece articulated cars with the first section 626 connected to a second section 628 by a coupling 630. The first and second sections 626, 628 each include a base configured to engage the guide path 612. The first section 626 includes a resilient member (e.g., a fixed metal bar, spring member, etc.) 632 biased towards the second section 628. The second section 628 includes a cup shaped member sized to receive the cube being coated. The cup shaped member of the second section 628 defines drain holes (not shown) that allow solution to escape the cup shaped member and drain back, for example into the appropriate reservoir.
(138) Having a two-piece movable car as in this prototype system has several advantages. For example, there may be specific points along the guide path 612 where a conveyor belt cannot be in contact with a base component of movable car 610. Having two sections 626 and 628 permits one section to continue to be in contact with the conveyor belt even if the other is over a section where contact with the conveyor belt is impossible. This allows, for example, section 628 to “push” section 626 forward as the movable cars 610 move up and out of reservoir 614, since in one embodiment of system 600 tested, conveyor belt 618 passes under a guiding rod at a point near the exit of guide path 612 from reservoir 614, and at this specific point contact between both movable cars of 610 simultaneously is not possible. This particular feature of the embodiment of system 600 tested also requires that the coupling 630 be of a rigid material.
(139) In operation of the prototype system 600, the object to be coated was manually placed in the movable car 610. Possible automated loading systems are discussed below in the description of
(140) As the movable car 610 lifts the object being coated out of the first reservoir 614, excess solution drains off of the object and movable car 610 through the drain holes defined in the cup shape of the second section 628 of the movable car 610. Moving along the guide path, the movable car 610 disengages from the first conveyor belt 618 and engages the second conveyor belt 620. The sequence is repeated with the second reservoir 616. After leaving the second reservoir 616, the guide path and, thus, the movable car 610 was inverted to release the coated object from the movable car 610. In this sample embodiment, the guide path 612 allows the movable car 610 to advance by gravity alone after disengaging from conveyor belt 620. This is facilitated by the natural motion of the object to be coated from section 628 to 626 due to the slant of the guide path 612, which further propels movable car 610 forward by momentum.
(141) It should be noted generally that the two sections 628 and 626 of movable car 610 have been designed, in this sample embodiment, to facilitate transport and coating of the object with a simple design and no mechanized parts. In other embodiments, a single-car system could be used with a mechanized open/close door function, to allow for contact with reservoir fluid, retrieval of the object for transport to the next reservoir, etc.
(142) This prototype demonstrated the possibility of industrial production of the edible bottles based on the methods described previously. Placed in a controlled sterile environment, the mechanized system can be configured to produce between 100 and 300 edible bottles per hour. Production can increase through the use of multiple rails, motors, and ice producing machines.
(143)
Other Embodiments
(144) A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention.
(145) For example, food transport systems can also be formed by spraying droplets of food liquid from a tube with an annulus around the tube that sprays an enveloping membrane material. In one embodiment, the tube sprays water containing calcium and the annulus sprays chemically-modified alginates as described above. When the droplets come out of the tube covered with the membrane, the droplets are exposed to UV light and possibly suspended in the air for some period of time to be allowed to harden.
(146) In another example, the droplets may be sprayed with just a sodium alginate membrane and, in the air, coated with the chemically modified alginates as described above. The droplets would then be exposed to UV light and possibly suspended in the air for some period of time to be allowed to harden.
(147) In another example, the droplets may be sprayed with a sodium alginate membrane and, in the air, hardened/cured with calcium as described above.
(148) In some embodiments, containers include a PLA outer shell and use inner membranes ranging from the sodium alginate membranes to edible waxes of the kinds used on fine chocolates occasionally. The latter have a distinct advantage of repelling water. Some embodiments may contain one or more combinations of such materials as “shells” or “membranes”, for example, a sodium alginate membrane, hardened/cured with calcium, may be covered with an edible wax and then placed within a PLA shell.
(149) In some embodiments, multiple inner containers can be protected by a single outer shell. For example,
(150) Accordingly, other embodiments are within the scope of the following claims.