AQUEOUS PRODUCT COMPRISING OIL-CONTAINING MICROCAPSULES AND
METHOD FOR THE MANUFACTURE THEREOF
PRIORITY CLAIM
[0001] This application claims priority to U.S. Utility Application Serial
No. 13/425,941 filed March 21, 2012, and titled "Aqueous Product Comprising
Oil-Containing Microcapsules and Method for the Manufacture Thereof
(Attorney Docket No. 056943.00966), and the entire disclosure of which is
hereby incorporated by reference.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to the field of protecting a hydrophobic substance
in an acidic aqueous system, more particularly microcapsules containing
hydrophobic substances in acidic aqueous systems such as food products.
BACKGROUND OF THE INVENTION
[0003] Certain hydrophobic substances are desirable as ingredients in food products,
such as in, for example, beverages. In some cases such a hydrophobic substance
does not have an acceptable taste or taste profile or is not sufficiently stable in
an acidic environment. Examples of such hydrophobic substances include
omega-3 fatty acids, water-insoluble flavorants, water-insoluble vitamins, etc.
Certain hydrophobic substances have been discovered to have beneficial health
effects. For example, omega-3 and omega-6 fatty acids form an important part
of the human diet. Eicosapentaenoic acid (EPA) and docosahexaenoic acid
(DHA), long-chain forms of omega-3 fatty acids, are understood in many cases
to support brain and cardiovascular health and functions, amongst other health
benefits. It has been suggested that consumption of omega-3 fatty acids should
be increased.
[0004] Previously, hydrophobic substances have been incorporated directly into an
aqueous system as a solution (with a compatible solvent), an extract, an
emulsion, or a micellular dispersion (a so-called microemulsion). While all of
these approaches serve to disperse the hydrophobic substance in an aqueous
system, they do not provide extended protection against hydrolysis and
oxidation. Commercially available fish oils, for example, can be high in omega-
3 fatty acids, and in some cases are "encapsulated," but these commercially
available fish oils have not proven adequately stable in all food contexts, e.g.,
physically or taste-stable in acidic food products. This can result in negative
changes to the food product, such as unpleasant fishy flavors and aromas after
ingestion, particularly a fishy aftertaste caused by belching fish oil from the
stomach. Additionally, omega-3 fatty acids, as well as many water-insoluble
flavorants, water-insoluble vitamins, etc. are unstable to degradation, e.g., by
oxidation or hydrolysis, when exposed to air, water and/or light.
It would be desirable to provide edible compositions suitable for use in food
products, which compositions incorporate one or more hydrophobic substances.
It also would be desirable to provide food products incorporating such edible
compositions. At least certain of the embodiments of the new compositions
disclosed below can reduce or eliminate the unpleasant taste and odor of the one
or more incorporated hydrophobic substances when used as an ingredient in a
food product suitable for consumption by a human or animal. At least certain of
the embodiments of the new compositions disclosed below provide hydrophobic
substances in a stable form for use in aqueous systems such as food products. In
at least some embodiments the hydrophobic substance is stable to oxidation and
hydrolysis during the shelf life of the food product. In at least some
embodiments the hydrophobic substance is stable to oxidation and hydrolysis in
an acidic food product, e.g., a food product at pH less than pH 5.0 and in some
cases less than pH 3.5. Additional features and advantages of some or all of the
food products disclosed here will be apparent to those who are skilled in food
technology given the benefit of the following summary and description of nonlimiting
examples.
SUMMARY
[0006] Aspects of the invention are directed to delivery systems for hydrophobic
substances which may be incorporated into food products, such as, for example,
an acidic food product. By encapsulating a hydrophobic substance in
microcapsules formed from polysaccharide glycated protein, one or more
negative effects (e.g., oxidation, off flavor, unpleasant aroma, etc.) can be
reduced or eliminated.
[0007] In one aspect, a food product is provided comprising an aqueous dispersion of
microcapsules, wherein the microcapsules have at least one hydrophobic
substance and a proteinaceous interface surrounding the at least one
hydrophobic substance, wherein the proteinaceous interface comprises
polysaccharide glycated protein, and the polysaccharide glycated protein
comprises at least one protein residue and at least one polysaccharide residue,
and a second food ingredient with the aqueous dispersion of microcapsules.
Reference here to the proteinaceous interface being "around" the hydrophobic
substance, and alternative terms used below, such as surround,
microencapsulate, microcapsulate, etc. are used interchangeably and should be
understood to mean that the proteinaceous interface effectively isolates or
otherwise protects the hydrophobic substance (regardless whether or not it
perfectly or completely surrounds the hydrophobic substance), e.g., for better
taste profile, resistance to oxidation, resistance to hydrolysis and/or any
combination of these or other purposes.
[0008] In certain embodiments, i.e., non-limiting examples or embodiments, of the
delivery system, aqueous dispersion, and food product aspects disclosed here,
the at least one polysaccharide residue of the polysaccharide glycated protein
has a molecular weight of at least 5kDa, at least 200kDa, or no more than
lOOOkDa, and is selected from pullulan residue, dextran residue, guar gum
residue, locust bean gum residue, tara gum residue, pectin residue, and
combinations of any of them. In certain embodiments the at least one protein
residue comprises at least one of whey protein residue, ovalbumine residue,
lysozym residue, potato protein residue, soy protein residue, zein residue, and
gluten residue. In certain embodiments the protein residue consists essentially
of whey protein residue, ovalbumine residue, lysozym residue, potato protein
residue, soy protein residue, zein residue, gluten residue or a combination of any
of them. In certain embodiments the hydrophobic substance comprises or
consists essentially of one or more lipids, water-insoluble vitamins, waterinsoluble
sterols, water-insoluble flavonoids, flavors, essential oils and
combinations of any of them. In certain embodiments the at least one
polysaccharide residue is a pullulan residue, the at least one protein residue is a
whey protein residue, and the hydrophobic substance includes an omega-3 fatty
acid. In certain embodiments the food product is a beverage, and in some
embodiments the food product is an acidic beverage.
[0009] In a second aspect, a method is provided for preparing an aqueous dispersion of
microcapsules comprising a) preparing a solution of a protein and a
polysaccharide, b) freeze drying the solution of the protein and the
polysaccharide (optionally referred to here, for convenience, as a
protein/polysaccharide solution) to form a freeze dried product, c) heating the
freeze dried product to form polysaccharide glycated protein, d) combining and
homogenizing water, a hydrophobic substance, and the polysaccharide glycated
protein into an emulsion with the polysaccharide glycated protein accumulating
at or as a proteinaceous interface of the hydrophobic substance and the water,
thereby producing a solution of microcapsules.
[0010] In certain embodiments of the method aspects disclosed, the solution of protein
and polysaccharide comprises 10-20% of the protein and 10-25% of the
polysaccharide. As used here all percentage values (unless expressly stated
otherwise) are percent by weight of the entire composition or material referred
to (e.g., in the preceding sentence, the entire "solution of protein and
polysaccharide"). In certain such embodiments the solution of protein and
polysaccharide is heated at 40-60°C, 40-80% relative humidity, for 24-48 hours
to form the polysaccharide glycated protein. In certain embodiments the
emulsion of polysaccharide glycated protein, water and hydrophobic substance
has a pH of about pH 6.0 to pH 7.0.
[001 1] In a third aspect, an aqueous dispersion of microcapsules is produced by a
method comprising a) preparing a solution of a protein and a polysaccharide, b)
freeze drying the solution of the protein and the polysaccharide, c) heating the
freeze dried solution of the protein and the polysaccharide to form
polysaccharide glycated protein, d) combining water, a hydrophobic substance,
and the polysaccharide glycated protein and homogenizing, and e) allowing the
polysaccharide glycated protein to accumulate at the interface of the
hydrophobic substance and the water, thereby producing microcapsules.
[0012] In a fourth aspect, a microcapsule is provided having at least one hydrophobic
substance and a layer around the at least one hydrophobic substance. The layer
comprises polysaccharide glycated protein. The polysaccharide glycated protein
comprises at least one protein residue and at least one polysaccharide residue.
[0013] In a fifth aspect, an aqueous dispersion of microcapsules is provided wherein the
microcapsules have at least one hydrophobic substance and a layer around the at
least one hydrophobic substance. The layer comprises polysaccharide glycated
protein. The polysaccharide glycated protein comprises at least one protein
residue and at least one polysaccharide residue.
[0014] In a sixth aspect, a food product is provided comprising microcapsules having at
least one hydrophobic substance and a layer around the at least one hydrophobic
substance, wherein the layer comprises polysaccharide glycated protein, and
wherein the polysaccharide glycated protein comprises at least one protein
residue and at least one polysaccharide residue.
[0015] In a seventh aspect, an aqueous dispersion of microcapsules is provided,
wherein the microcapsules comprise at least one hydrophobic substance
comprising omega-3 fatty acids, and a proteinaceous interface around the at
least one hydrophobic substance, wherein the proteinaceous interface comprises
polysaccharide glycated protein comprising at least one whey protein residue
and at least one pullulan residue. In some embodiments the proteinaceous
interface has a mean thickness of 0.005-10.0 m.
[0016] In at least certain embodiments the microcapsules disclosed here (also referred
to here in the alternative and interchangeably as oil-containing microcapsules,
microcapsules containing hydrophobic substance, polysaccharide glycated
protein based microcapsules, PGP based microcapsules, etc.) and food products
incorporating them as an ingredient have been found to have unanticipated,
desirable properties. For example, in certain such embodiments the
polysaccharide glycated protein (PGP) based microcapsules can remain
suspended in aqueous systems, e.g., beverages, beverage concentrates, etc., for a
surprisingly long period of time. In certain such embodiments the PGP based
microcapsules can remain suspended in acidic aqueous systems, e.g., beverages,
beverage concentrates, etc. having a pH value less than pH 7.0 and in some
cases less than pH 3.5, for a surprisingly long period of time. Furthermore, it
was found that in at least some embodiments the PGP-containing interface layer
effectively protects the hydrophobic substance in the microcapsules against
oxidation and/or hydrolysis, etc.
[0017] These and other aspects, advantages and features of the present invention here
disclosed will become apparent through reference to the following detailed
description. Furthermore, it is to be understood that the features of the various
embodiments described here are not mutually exclusive and exist in various
combinations and permutations in other embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In the drawings, like reference characters generally refer to the same parts
throughout the different views. Also, the drawing is not necessarily to scale,
emphasis instead generally being placed upon illustrating the principles of the
invention. In the following description, various embodiments of the present
invention are described with reference to the following drawing, in which:
[0019] Figure 1 is a schematic of a microcapsule in accordance with one embodiment
of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Various examples and embodiments of the inventive subject matter disclosed
here are possible and will be apparent to the person of ordinary skill in the art,
given the benefit of this disclosure. In this disclosure reference to "certain
exemplary embodiments" (and similar phrases) means that those embodiments
are merely non-limiting examples of the inventive subject matter and that there
likely are other alternative embodiments which are not excluded. Unless
otherwise indicated or unless otherwise clear from the context in which it is
described, alternative elements or features in the embodiments and examples
below and in the Summary above are interchangeable with each other. That is,
an element described in one example may be interchanged or substituted for one
or more corresponding elements described in another example. Similarly,
optional or non-essential features disclosed in connection with a particular
embodiment or example should be understood to be disclosed for use in any
other embodiment of the disclosed subject matter. More generally, the elements
of the examples should be understood to be disclosed generally for use with
other aspects and examples of the devices and methods disclosed here. A
reference to a component or ingredient being operative, i.e., able to perform one
or more functions, tasks and/or operations or the like, is intended to mean that it
can perform the expressly recited function(s), task(s) and/or operation(s) in at
least certain embodiments, and may well be operative to perform also one or
more other functions, tasks and/or operations. While this disclosure includes
specific examples, including presently preferred modes or embodiments, those
skilled in the art will appreciate that there are numerous variations and
modifications within the spirit and scope of the invention as set forth in the
appended claims. Each word and phrase used in the claims is intended to
include all its dictionary meanings consistent with its usage in this disclosure
and/or with its technical and industry usage in any relevant technology area.
Indefinite articles, such as "a," and "an" and the definite article "the" and other
such words and phrases are used in the claims in the usual and traditional way in
patents, to mean "at least one" or "one or more." The word "comprising" is
used in the claims to have its traditional, open-ended meaning, that is, to mean
that the product or process defined by the claim may optionally also have
additional features, elements, etc. beyond those expressly recited. The phrase
"consisting essentially of is used to signal that the product or process defined
necessarily includes the listed ingredients and is open to unlisted ingredients that
do not materially affect the basic and novel properties of the invention.
[0021] Aspects of the invention relate to microcapsules disclosed here for hydrophobic
substances, which provide a stable composition suitable for inclusion in food
products, that is the microcapsules are stable for shelf-storage, for use in making
food products, and for shelf-storage when included in acidic food products, etc.
The microcapsules reduce or eliminate the unpleasant taste and odor of many
hydrophobic substances such as fish oil, and reduce degradation, e.g. by
oxidation or hydrolysis, of unstable hydrophobic substances. The microcapsules
may be incorporated into a food product associated with health benefits, for
example orange juice, to provide enhanced nutritional value. Additionally, the
microcapsules may be incorporated into food products, for example carbonated
soft drinks. By encapsulating such hydrophobic substances in microcapsules,
possible negative visual and physical changes to the food product may be
reduced or avoided. The resulting food product is appealing to the consumer, as
well as being stable and having an adequate shelf life.
[0022] In certain embodiments microcapsules are provided in an aqueous dispersion.
As used here an "aqueous dispersion" is defined as particles distributed
throughout a medium of liquid water, e.g., as a suspension, a colloid, an
emulsion, a sol, etc. The medium of liquid water may be pure water, or may be
a mixture of water with at least one water-miscible solvent, such as, for
example, ethanol or other alcohols, propylene glycol, glycerin,
dimethylsulfoxide, dimethylformamide, etc. In certain embodiments there may
be a substantial concentration of water-miscible solvent in the aqueous
dispersion of the microcapsules, such as, at least 1% by volume, between about
1% and about 20% by volume, or no more than 20% by volume, for example
5%>, 10% , or 15%o by volume. In other embodiments the microcapsules are
diluted into a food product and the concentration of water-miscible solvent is
negligible.
[0023] As used here "microcapsule" is defined as a clearly identifiable discrete particle
containing one or more hydrophobic substances, e.g. oil, water-insoluble
vitamins, flavors, etc. that are enveloped by a proteinaceous interface, also
referred to here as a proteinaceous interface layer, that separates said
hydrophobic substances from the environment surrounding the particle. In
certain embodiments there may be clearly identifiable discrete clusters (e.g.
agglomerates) of the aforementioned particles.
[0024] As used here a "hydrophobic substance" refers to a water immiscible material
such as an oil, a lipid, a water-insoluble vitamin (e.g. a-tocopherol), a waterinsoluble
sterol, a water-insoluble flavonoid, a flavor or an essential oil. The oil
employed in accordance with the present invention can be a solid, a liquid or a
mixture of both.
[0025] As used here a "lipid" encompasses any substance that contains one or more
fatty acid residues, including free fatty acids. Thus, the term "lipid"
encompasses, for instance, triglycerides, diglycerides, monoglycerides, free fatty
acids, phospholipids or a combination of any of them.
[0026] As used here a "fatty acid" encompasses free fatty acids as well as fatty acid
residues. Whenever reference is made here to a weight percentage of fatty
acids, this weight percentage includes free fatty acids as well as fatty acid
residues (e.g. fatty acid residues contained in triglycerides). Further, as used
here a "polyunsaturated fatty acid" (PUFA) encompasses any fatty acid
containing 2 or more double bonds in the carbon chain.
[0027] As used here a "polysaccharide glycated protein" or "PGP" is a molecule, that
may be a true protein in which at least one polysaccharide residue is covalently
or otherwise bonded to at least one protein residue. PGP is typically formed
when sugars are cooked with proteins causing Browning reactions (usually
Maillard type reactions). As used here "polysaccharide residue" refers to the
part of the PGP that originates from a polysaccharide. Likewise, "protein
residue" refers to the part of the PGP that originates from a protein. "Residue"
refers to the moiety or constituent of the polysaccharide or protein that forms the
polysaccharide glycated protein.
[0028] As used here "polysaccharide" refers to polymeric carbohydrate structures that
comprise monosaccharides units joined together by glycosidic bonds. These
structures may be linear, or they may contain various degrees of branching.
Polysaccharides typically contain between 20 and 1000 monosaccharide units.
[0029] As used here "protein" refers to a polymer built from amino acids arranged in a
chain and joined together by peptide bonds between the carboxyl and amino
groups of adjacent amino acid residues. Typically, the protein contains at least
10 amino acid residues. The protein employed in accordance with the present
invention can be, for instance, an intact naturally occurring protein, a protein
hydrolysate or a synthesised protein.
[0030] As used here an "interface" or "interface layer" is the layer that separates the
one or more hydrophobic substances in the microcapsule from the surrounding
environment (e.g. an aqueous liquid or a gaseous atmosphere). As used here a
"proteinaceous interface" or "proteinaceous interface layer" is an interface layer
that, water excluded, contains at least 25 wt.%, preferably at least 50 wt.% of
protein and/or protein derivatives, such as PGP. The interface layer in some, but
not necessarily all embodiments, has a uniform thickness. Further, it need not
necessarily be a continuous layer, but rather may be discontinuous, irregular or
the like, so long as it is effective as an interface between the hydrophobic
substance(s) and the aqueous medium in which the microcapsules are dispersed.
In some embodiments the proteinaceous interface layer is comprised of a
number of protein molecules, some of which include a polysaccharide tail
(PGP). In many embodiments the polysaccharide tail on the PGP molecules
may induce a repulsive interaction with other microcapsules, thereby preventing
aggregation and contributing to steric stability of the microcapsule.
[0031] In certain embodiments an aqueous solution is prepared comprising at least one
protein and at least one polysaccharide. In at least some such embodiments the
at least one protein comprises or consists essentially of any food grade
protein(s). Certain non-limiting examples of the at least one protein include, for
example, whey protein, such as beta-lactoglobulin, alpha-lactalbumin, whey
protein isolate, whey protein concentrate, ovalbumine, lysozym, potato protein,
soy protein, zein, gluten, pea protein, meat protein or a combination of any of
them. The at least one polysaccharide in at least some embodiments comprises
or consists essentially of any high molecular weight polysaccharide. Certain
non-limiting examples of the at least one polysaccharide include, for example,
pullulan, dextran, guar gum, locust bean gum, tara gum, pectin, or combinations
of any of them. In certain embodiments the solution of the at least one protein
and the at least one polysaccharide comprises 10-20 wt.% of the at least one
protein and 10-25 wt.% of the at least one polysaccharide. In some
embodiments the ratio of polysaccharide to protein may be, for example, 1:50 to
2:1. In alternative embodiments the ratio of polysaccharide to protein may be,
for example, 1:10. In certain embodiments the solution of the at least one
protein and the at least one polysaccharide is subjected to mixing, such as, high
shear mixing. In certain embodiments the high shear mixing may occur at 5000
rpm for 10 min.
[0032] In certain embodiments the solution of the at least one protein and the at least
one polysaccharide is freeze dried so as to combine the at least one protein and
the at least one polysaccharide at the molecular level. The solution may be
freeze dried by any method known by those of skill in the art. For example, the
solution may be placed in a freeze-drying tray, which is then placed in a space
connected to a cold area (-40°C) which is pumped to vacuum (ca 10 5 bar) for 24
hours. Any standard freeze drying setup may be utilized.
[0033] In alternative embodiments the at least one protein and the at least one
polysaccharide may be combined at the molecular level by subjecting a
combination of the at least one protein and the at least one polysaccharide to
mechanical grinding, for example, by ball milling, mortar and pestle or any
other form of trituration.
[0034] In some embodiments the freeze dried product of the at least one protein and the
at least one polysaccharide is heated, to form a polysaccharide-glycated protein
(PGP). In certain embodiments the freeze dried product is heated at 40-60°C
and 40-80% relative humidity for 24-48 hours. In some embodiments the freeze
dried product is heated at 60°C and 60% relative humidity for 24-48 hours. In
certain embodiments the heating of the freeze-dried product causes a Maillard
reaction thereby forming PGP.
[0035] PGP formed from a Maillard reaction comprises at least one polysaccharide
residue and at least one protein residue. In certain embodiments the at least one
protein residue comprises a whey protein residue, an ovalbumine residue, a
lysozym residue, a potato protein residue, a soy protein residue, a zein residue, a
gluten residue, or a combination of any of them. Additionally, in certain
embodiments the at least one polysaccharide residue comprises a pullulan
residue, a dextran residue, a guar gum residue, a locust bean gum residue, a tara
gum residue, a pectin residue, or a combination of any of them.
[0036] In certain embodiments the polysaccharide residue contains at least 90 wt.% of
monosaccharide units comprising at least one of glucose, fructose, arabinose,
galactose, and derivatives of glucose, fructose, arabinose, and galactose. In
certain embodiments the polysaccharide residue is a homopolymer comprising
at least 90 wt.% of the same monosaccharide units. In certain embodiments the
polysaccharide residue contained in the PGP has a molecular weight, for
example, of at least 5 kDa, 10 kDa, 100 kDa, or 200 kDa as determined by Size
Exclusion Chromatography analysis. In certain embodiments the
polysaccharide residue contained in the PGP has a molecular weight that shall
not exceed 1000 kDAa.
[0037] In certain embodiments an emulsion is prepared by combining PGP with water
and a hydrophobic substance. In certain embodiments the hydrophobic
substance is, for example, an oil droplet. Droplet is used to refer to an amount
of a substance, e.g., oil, that is bounded completely or almost completely by free
surfaces. In certain embodiments the droplet may have a defined shape, e.g.,
may be generally spherical in shape. In certain embodiments the oil droplet is a
lipophilic nutrient or a water-insoluble flavorant. In some embodiments the oil
droplet may contain a lipophilic nutrient or a water-insoluble flavorant in
combination with an antioxidant (e.g., a-tocopherol, carotenes, and ubiquinol).
[0038] In certain embodiments the lipophilic nutrients may comprise or consist
essentially of fat soluble vitamins, (e.g., vitamins A, D, E, and K), tocotrienols,
carotenoids, xanthophylls, (e.g., lycopene, lutein, astaxanthin, and zeazanthin),
fat-soluble nutraceuticals including phytosterols, stanols and esters thereof,
Coenzyme Q10 and ubiquinol, hydrophobic amino acids and peptides, essential
oils and extracts, and fatty acids. Fatty acids may include, for example,
conjugated linolenic acid (CLA), omega-6 fatty acids, and omega-3 fatty acids.
Suitable omega-3 fatty acids include, e.g., short-chain omega-3 fatty acids such
as alpha-linolenic acid (ALA), which are derived from plant sources, for
example flaxseed, and long-chain omega-3 fatty acids such as eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA). In certain embodiments the
long-chain omega-3 fatty acids can be derived from, for example, marine or
fish oils. Such oils can be extracted from various types of fish or marine
animals, such as anchovies, capelin, cod, herring, mackerel, menhaden, salmon,
sardines, shark and tuna, or from marine vegetation, such as micro-algae, or a
combination of any of them. Other sources of omega-3 fatty acids include
liver and brain tissue and eggs.
[0039] In certain embodiments the water-insoluble flavorant may comprise or consist
essentially of any substance that provides a desired flavor to a food or beverage
product, which does not substantially dissolve in water (e.g., non-polar,
hydrophobic substances such as lipids, fats, oils, etc.). In certain embodiments
the flavorant may be a liquid, gel, colloid, or particulate solid, e.g., an oil, an
extract, an oleoresin, or the like. Exemplary water-insoluble flavorants include,
but are not limited to, citrus oils and extracts, e.g. orange oil, lemon oil,
grapefruit oil, lime oil, citral and limonene, nut oils and extracts, e.g. almond oil,
hazelnut oil and peanut oil, other fruit oils and extracts, e.g. cherry oil, apple oil
and strawberry oil, botanical oils and extracts, e.g., coffee oil, mint oil, vanilla
oil, and combinations of any of them.
[0040] In certain embodiments, water, a hydrophobic substance, and PGP are combined
to form an oil-in-water emulsion. In certain embodiments the emulsion
comprises PGP, water, a hydrophobic substance, and at least one of a second
protein, a second polysaccharide, and a pectin. In some embodiments the
second protein and the second polysaccharide may be non-reacted protein and
polysaccharide in the PGP material. In certain embodiments the emulsion is
homogenized after the combining of the water and oil, alternatively after the
combining of the water, the oil, and the PGP. In certain embodiments the
homogenization is a two-stage high pressure homogenization process (i.e., 800
and 80 bar). In alternative embodiments the emulsion may be formed by other
methods known in the art, including microfluidic emulsification, piston type
emulsification, or membrane emulsification. In certain embodiments after
homogenization, the PGP and the at least one of a second protein, a second
polysaccharide, and a pectin accumulate at the interface of the water and the oil
forming a proteinaceous interface and thereby forming microcapsules in an
aqueous dispersion. In certain embodiments an acidulant and/or chemical
preservative may be added, prior to, during, or after formation of the emulsion.
Non-limiting examples of an acidulant include, for example, citric acid, Glucono
delta-lactone, adipate, phosphoric acid, acetic acid, and tartaric acid. Nonlimiting
examples of a chemical preservative include, for example, sodium
hexameta phosphate (SHMP), calcium propionate, calcium sorbate, potassium
sorbate, sodium citrate, potassium citrate, calcium benzoate, sodium benzoate,
potassium benzoate, sodium nitrate, sodium chloride, sulphur dioxide,
natamycin, nisin, sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen
sulfite, etc.) and disodium EDTA. Alternatively, the emulsion may be treated
with anti-microbials, radiation, heat processing, e.g., pasteurization using ultra
high temperature (UHT) treatment and/or high temperature-short time (HTST)
treatment, or packaged aseptically.
[0041] In certain embodiments an emulsion may comprise or consist essentially of
PGP, water, a hydrophobic substance, and at least one of a second protein, a
second polysaccharide, or combinations of any of them. In certain embodiments
the PGP and at least one of the second protein, the second polysaccharide, or
combinations of any of them accumulate to form a proteinaceous interface. In
certain embodiments an interface layer has a dry weight composition comprising
0.1-100 wt.% PGP, 0-99.99 wt.% second protein, and 0-75 wt.% second
polysaccharide, wherein the PGP, second protein, and second polysaccharide
represent at least 80 wt.%, or further, at least 90 wt.% of the interface layer's dry
weight composition. In an alternative embodiment an interface layer has a dry
weight composition comprising 0.25-30 wt.% PGP, 20-99.75 wt.% protein, and
0-50 wt.% polysaccharide. In a further embodiment an interface layer has a dry
weight composition comprising 0.5-25 wt.% PGP, 20-95.5 wt.% second protein,
and 2-40 wt.% second polysaccharide.
[0042] The amount of PGP employed in forming the proteinaceous interface layer of
the microcapsules can vary widely and depends, amongst other things, on the oil
droplet size. In certain embodiments the microcapsules contain 0.1-50% PGP
by weight of dry matter. In alternative embodiments the microcapsules contain,
for example, 0.25-10% PGP by weight of dry matter basis or, in an another
embodiment, 0.5% to 5% PGP by weight of dry matter. In certain embodiments
the mean thickness of the proteinaceous interface layer of microcapsules is
within the range of, for example, 0.005 to 10 mih, 0.05 to 5 mih, or 0.1 to 1 mih.
The thickness of the proteinaceous interface layer may be measured, for
example, by centrifuging the emulsion and using infrared or Raman spectra of
the microcapsule containing creamed material that forms after centrifugation, or
using microscopy, e.g., transmission electron microscopy (TEM).
[0043] In some embodiments an emulsion may comprise or consist essentially of PGP,
water, a hydrophobic substance, and pectin. The pectin may be selected, for
example, from the group comprising a high ester (HM) pectin (>50%
esterification), a low ester (LM) pectin (<50% esterification), an amidated
pectin, and combinations of any of them. In some embodiments the pectin is a
high methyl ester pectin. In certain embodiments the pectin is more than 75%
esterified. In certain embodiments the pectin is a citrus pectin. In certain
embodiments the pectin has a molecular weight of, for example, 60 kDa-500
kDa or 100 kDa-200 kDa g/mol. In certain embodiments the proteinaceous
interface layer comprises pectin in a concentration, for example, of at least 0.5%
or at least 10%> by weight of dry matter, and not exceeding 75% by weight of
dry matter.
[0044] In certain embodiments the emulsion comprises, for example, 0.01-45 wt.%, or
alternatively 0.01-20 wt.% of dispersed oil; 0.001-10 wt.%, or alternatively
0.01-3 wt.% or alternatively 0.001-2 wt.% of PGP; 0-30 wt.%, or alternatively
0.05-10 wt .% of biopolymer selected from the group consisting of proteins,
polysaccharides and combinations of any of them; 50-99.989 wt.%, or
alternatively 70-99.3 wt.% of water; and wherein the various constituents
together represent, for example, at least 95 wt.%, or in certain embodiments at
least 98 wt.% of the emulsion.
[0045] In certain embodiments the oil droplets contain, for example, at least 3 wt.%, at
least 5 wt.%, no more than 10 wt.%, or alternatively no more than 30 wt.%,
polyunsaturated fatty acids selected from omega-3 fatty acids, omega-6 fatty
acids and combinations of any of them. In certain embodiments the one or more
polyunsaturated fatty acids are selected from DHA, EPA, CLA and
combinations of any of them. In some embodiments the oil droplets contain, for
example, at least 5 wt.%, or alternatively no more than 10 wt.% polyunsaturated
fatty acids selected from DHA, EPA, CLA and combinations of any of them.
[0046] In certain embodiments the microcapsules of the present invention have a
volume weighted average diameter in the range of 0.1-500 um, 0.1-100 mih, 0.3-
50 mih, 0.5-30 mih, or 0.7-20 mih. In certain embodiments the oil droplets in the
microcapsules have a mean diameter in the range of, for example, 0.01-20 mih or
0.1-10 mih. The microcapsule size disclosed here includes any or at least one
value within the disclosed ranges as well as the endpoints of the ranges. The
microcapsule size may be measured by any method known to those of skill in
the art, including by microscopy or laser light scattering.
[0047] In certain embodiments the oil droplets represent, for example, at least 5 wt.%,
at least 10 wt.%, at least 20 wt.%>, or at least 35 wt.%> of the microcapsule. In
certain embodiments the oil droplets represent not more than 80 wt.% of the
microcapsules. In certain embodiments the oil droplets typically have a melting
point of, for example, less than 40°C, less than 30°C, or less than 15°C.
[0048] Certain embodiments of the aqueous dispersions disclosed here can be prepared
at a neutral pH of, for example, about 6.0 to 7.0. In certain embodiments the
neutral aqueous dispersion can then be added to a food product, e.g., an acidic or
neutral food product that may be at a pH of, for example, at least pH 1.0, pH 1.0
to pH 7.0, pH 1.0 to pH 5.5, not more than pH 7.0, or not more than pH 5.5. In
some embodiments the aqueous dispersion of microcapsules is added to a food
product having a final pH value (i.e., a pH value in the fully prepared, aspackaged
product) at or below 3.5. In some embodiments the aqueous
dispersion of microcapsules is added to a food product having a final pH value
at or below 3.0.
[0049] In certain embodiments the aqueous dispersion of the present invention may
contain other dispersed components in addition to the microcapsules. In certain
embodiments the dispersion contains less than 20 wt.% of one or more dispersed
edible components, including the dispersed microcapsules.
[0050] In certain embodiments the microcapsules are not substantially additionally
stabilized, for example by substantial gelling, substantial crosslinking, or
substantial hardening of the microcapsules.
[0051] In certain embodiments the aqueous dispersion of microcapsules is maintained
as an aqueous dispersion. In alternative embodiments the aqueous dispersion of
microcapsules is, for example, spray dried, freeze dried, drum dried, or bed
dried. If maintained as an aqueous dispersion, in certain embodiments, the
aqueous dispersion of microcapsules is treated to protect from microbiological
growth. In certain embodiments the aqueous dispersion of microcapsules is, for
example, pasteurized; aseptically packaged; treated with chemical preservatives,
non-limiting examples including, for example, sodium hexameta phosphate
(SHMP), calcium propionate, calcium sorbate, potassium sorbate, sodium
citrate, potassium citrate, calcium benzoate, sodium benzoate, potassium
benzoate, sodium nitrate, sodium chloride, sulphur dioxide, natamycin, nisin,
sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen sulfite, etc.) or
disodium EDTA; treated with acids, non-limiting examples including, for
example, citric acid, Glucono delta-lactone, adipate, acetic acid, phosphoric
acid, tartaric acid, succinic acid, or HCl; carbonated; or combinations of any of
them. In some embodiments the aqueous dispersion of microcapsules has no
contact or minimized contact with air during production, is pasteurized after
production, and is stored in a refrigerator with no exposure of with limited
exposure to light.
[0052] In certain embodiments the microcapsules are dispersed in a food product. In
certain embodiments the aqueous dispersion of microcapsules contains the
dispersed microcapsules in a concentration of, for example, 0.01-10% by
weight, or in certain embodiments 0.1-10% by weight of the continuous aqueous
phase. In certain embodiments the dispersed microcapsules are contained in the
aqueous dispersion in a concentration of 0.2-5% by weight of the aqueous
phase. In certain embodiments the aqueous dispersion contains a limited
amount of microcapsules and the continuous aqueous phase represents the bulk,
for example, at least 70 wt.%, 80-99.9 wt.%, or 90-99.8 wt.% of the aqueous
dispersion.
[0053] In certain embodiments the aqueous dispersion of microcapsules is a pourable
concentrate that can be used to deliver the microcapsules to food products. In
accordance with this embodiment the aqueous dispersion contains 10-50 wt.%
of the microcapsules and 50-10 wt.% of the continuous aqueous phase. In
certain embodiments the pH of the concentrated microcapsule composition lies
within the range of, for example, pH 1.0 to 4.8, or in certain embodiments
within the range of pH 1.0 to 4.0.
[0054] In certain embodiments a concentrated microcapsule composition is prepared
containing, for example, at least 1 wt.%, at least 5 wt.%, or at least 10 wt.% of
dispersed microcapsules. In certain embodiments the concentrated microcapsule
composition is combined with water and, in some embodiments, other
constituents to produce a food product. In certain embodiments the combining
of the concentrated microcapsule composition with water and other constituents
produces a dilution factor (final volume/volume of the concentrated
microcapsule composition), for example, of at least 3, or alternatively of at least
5. In certain embodiments the dilution factor does not exceed 1000.
[0055] In certain embodiments a desired amount of hydrophobic substance in the form
of the above-described microcapsules is included in a food product. The amount
of microcapsules, and hence the amount of hydrophobic substance included in
the food product may vary depending on the application and desired taste
characteristics of the food product. The microcapsules may be added to the food
product in any number of ways, as would be appreciated by those of ordinary
skill in the art given the benefit of this disclosure. In certain embodiments the
microcapsules are sufficiently mixed in the food product to provide a
substantially uniform distribution, for example a stable dispersion. Mixing
should be accomplished such that the microcapsules are not destroyed. If the
microcapsules are destroyed, oxidation of the hydrophobic substance may result.
The mixer(s) can be selected for a specific application based, at least in part, on
the type and amount of ingredients used, the viscosity of the ingredients used,
the amount of product to be produced, the flow rate, and the sensitivity of
ingredients, such as the microcapsules, to shear forces or shear stress.
[0056] Encapsulation of hydrophobic substances using the above-described
microcapsules stabilizes the hydrophobic substance by protecting it from
degradation by, for example, oxidation and hydrolysis. When included in an
acidic food product, the microcapsules can provide a stable dispersion of
hydrophobic substances over the shelf life of the food product. Factors that may
affect the shelf-life of the microcapsules include the level of processing the
product undergoes, the type of packaging, and the materials used for
packaging the product. Additional factors that may affect the shelf life of
the product include, for example, the nature of the base formula (e.g., an
acidic beverage sweetened with sugar has a longer shelf-life than an acidic
beverage sweetened with aspartame) and environmental conditions (e.g.,
exposure to high temperatures and sunlight is deleterious to ready-to-drink
beverages).
[0057] In certain embodiments the food product is a beverage product. In certain
embodiments the beverage product includes ready-to-drink beverages, beverage
concentrates, syrups, shelf-stable beverages, refrigerated beverages, frozen
beverages, and the like. In some embodiments the beverage product is acidic,
e.g. having a pH within the range below about pH 5.0, in certain embodiments a
pH value within the range of about pH 1.0 to about pH 4.5, or in certain
embodiments a pH value within the range of about pH 1.5 to about pH 3.8.
Beverage products include, but are not limited to, e.g., carbonated and noncarbonated
soft drinks, fountain beverages, liquid concentrates, fruit juice and
fruit juice-flavored drinks, sports drinks, energy drinks, fortified/enhanced water
drinks, soy drinks, vegetable drinks, grain-based drinks (e.g. malt beverages),
fermented drinks (e.g., yogurt and kefir) coffee beverages, tea beverages, dairy
beverages, and mixtures thereof. Exemplary fruit juice sources include citrus
fruit, e.g. orange, grapefruit, lemon and lime, berry, e.g. cranberry, raspberry,
blueberry and strawberry, apple, grape, pineapple, prune, pear, peach, cherry,
mango, and pomegranate. Beverage products include bottle, can, and carton
products and fountain syrup applications.
[0058] Certain embodiments of other food products disclosed here include fermented
food products, yogurt, sour cream, cheese, salsa, ranch dip, fruit sauces, fruit
jellies, fruit jams, fruit preserves, and the like. In certain embodiments the food
product is acidic, e.g. having a pH value within the range below about pH 5.0, in
certain embodiments a pH value within the range of about 1.0 to about 4.5, or in
certain embodiments a pH value within the range of about 1.5 to about 3.8.
[0059] The food product may optionally include other additional ingredients. In certain
embodiments additional ingredients may include, for example, vitamins,
minerals, sweeteners, water-soluble flavorants, colorings, thickeners,
emulsifiers, acidulants, electrolytes, antifoaming agents, proteins,
carbohydrates, preservatives, water-miscible flavorants, edible particulates,
and mixtures thereof. In certain embodiments other ingredients are also
contemplated. In some embodiments the ingredients can be added at various
points during processing, including before or after pasteurization, and before or
after addition of the microcapsules.
[0060] In at least certain embodiments food products disclosed here may be
pasteurized. In certain embodiments the pasteurization process may include, for
example, ultra high temperature (UHT) treatment and/or high temperature-short
time (HTST) treatment. The UHT treatment includes subjecting the food or
beverage product to high temperatures, such as by direct steam injection or
steam infusion, or by indirect heating in a heat exchanger. Generally, after the
product is pasteurized, the product can be cooled as required by the particular
product composition/configuration and/or the package filling application. For
example, in one embodiment, the food product is subjected to heating to about
185°F (85°C) to about 250°F (12FC) for a short period of time, for example,
about 1 to 60 seconds, then cooled quickly to about 36°F (2.2°C) +/10°F (5°C)
for refrigerated products, to ambient temperature for shelf stable or refrigerated
products, and to about 185°F (85°C) +/- 10°F (5°C) for hot-fill applications for
shelf-stable products. The pasteurization process is typically conducted in a
closed system, so as not to expose the food or beverage product to atmosphere
or other possible sources of contamination. In alternative embodiments other
pasteurization or sterilization techniques may also be useful, such as, for
example, aseptic or retort processing. In addition, multiple pasteurization
processes may be carried out in series or parallel, as necessitated by the food
product or ingredients.
[0061] Food products may, in addition, be post processed. In certain embodiments post
processing is typically carried out following addition of the microcapsules. Post
processing can include, for example, cooling the product solution and filling it
into a container for packaging and shipping. In certain embodiments post
processing may also include deaeration of the food product to less than 4.0 ppm
oxygen, preferably less than 2.0 ppm and more preferably less than 1.0 ppm
oxygen. In alternative embodiments deaeration and other post processing tasks
may be carried out prior to processing, prior to pasteurization, prior to mixing
with the microcapsules and/or at the same time as adding the microcapsules. In
addition, an inert gas (e.g., nitrogen or argon) headspace may be maintained
during the intermediary processing of the product and final packaging.
Additionally/alternatively, an oxygen or UV radiation barriers and/or oxygen
scavengers could be used in the final packaging.
[0062] The following examples are specific embodiments of the present invention, but
are not intended to limit it.
EXAMPLES
Example 1
Preparation of an aqueous dispersion of microcapsules containingfish oil
[0063] An aqueous dispersion of microcapsules in accordance with one exemplary
embodiment of the disclosure was prepared using the following method.
[0064] An aqueous solution of 10% native whey protein isolate (WPI) and 10%
pullulan (molar mass about 200 kDa) was subjected to high-shear mixing for 2
minutes, using a table top Turrax (5000 rpm) (percentages by weight). The
aqueous solution of whey protein and pullulan was then freeze dried for 24 hr
using a standard freeze drying unit. The freeze dried product was then held at
60°C and 60% relative humidity for 48 hours to obtain a polysaccharide
glycated protein containing product (PGP).
[0065] An emulsion was then prepared by high pressure homogenizing a mixture of
12% fish oil, 73%o water and 5% PGP product (percentages by weight) at 300-
800 bar. The emulsion was stored at 32°C (90°F) for 7 days and was then tested
for smell and taste. No noticeable oxidative decay of the fish oil was detected.
Example 2
Preparation of a beverage containingfish oil
[0066] The emulsion, prepared as described in Example 1, was added to an aqueous
solution having a pH of pH 3. The final oil concentration in the aqueous
solution was 0.072%> (by weight) fish oil.
[0067] The emulsion was stored at 32°C (90°F) for 7 days and was then tested for smell
and taste. No noticeable oxidative decay of the fish oil was detected. The visual
appearance of the emulsion was homogeneous with slight turbidity.
Example 3
Preparation of a beverage containingfish oil
[0068] An aqueous solution having an aqueous dispersion of microcapsules in
accordance with another exemplary embodiment of the disclosure was prepared
using the following method.
[0069] An aqueous solution of 10% native whey protein isolate (WPI) and 10%> dextran
(molar mass about 200 kDa) was subjected to high-shear mixing for 2 min,
using a table top Turrax (5000 rpm) (percentages by weight). The aqueous
solution of whey protein and dextran was then freeze dried for 24 hours using a
standard freeze drying set up. The freeze dried product was then held at 60°C
and 60% relative humidity for 48 hours to obtain a polysaccharide glycated
protein containing product (PGP).
[0070] An emulsion was then prepared by high pressure homogenizing a mixture of
12% fish oil, 73% water and 5% PGP product (percentages by weight) at 300-
800 bar. The emulsion was added to an aqueous solution having a pH of pH 3.
The final oil concentration in the aqueous solution was 0.072% (by weight) fish
oil.
[0071] The emulsion was stored at 32°C (90°F) for 7 days and was then tested for smell
and taste. No noticeable oxidative decay of the fish oil was detected. The visual
appearance of the emulsion was homogeneous with slight turbidity.
Example 4
Preparation of a beverage containingfish oil
[0072] An aqueous solution having an aqueous dispersion of microcapsules in
accordance with an alternative exemplary embodiment of the disclosure was
prepared using the following method.
[0073] An aqueous solution of 10%> native ovalbumin and 10%> pullulan (molar mass
about 200 kDa) was subjected to high-shear mixing for 2 minutes, using a table
top Turrax (5000 rpm) (percentages by weight). The aqueous solution of
ovalbumin and pullulan was then freeze dried for 24 hours using a standard
freeze drying set up. The freeze dried product was then held at 60°C and 60%
relative humidity for 48 hours to obtain a polysaccharide glycated protein
containing product (PGP).
[0074] An emulsion was prepared by high pressure homogenizing a mixture of 12%
fish oil, 73% water and 5% PGP product (percentages by weight) at 300-800
bar. The emulsion was then added to an aqueous solution having a pH of pH 3.
The final oil concentration in the aqueous solution was 0.072% (by weight) fish
oil.
[0075] The emulsion was stored at 32°C (90°F) for 7 days and was then tested for smell
and taste. No noticeable oxidative decay of the fish oil was detected. The visual
appearance of the emulsion was homogeneous with slight turbidity.
Example 5
Composition of the microcapsules
[0076] The emulsion described in Example 2 was centrifuged at 5000g for 60 min. A 2
mL sample was taken from the oil containing turbid layer on top of the solution
by means of a pipette and freeze dried using a standard freeze drying set up.
Next, the sample was analysed with respect to protein (WPI), polysaccharide
(pullulan) and polysaccharide glycated protein (PGP) content by Infra Red
spectroscopy and Size Exclusion Chromatography. The content of free amino (-
NH2) groups was determined from the absorption of light at 340nm in solutions
containing the material, as well as ortho-phthalaldehyde (OPA), N,N-dimethyl-
2-mercaptoethyl-ammominium chloride, borax and sodium dodecyl sulfate
(SDS).
[0077] The results showed that the encapsulate material, surrounding the oil droplets
consisted of 65%> protein, 35% polysaccharide, and that at least 4.5% of the
protein had reacted with pullulan to form PGP.
The invention has been described with reference to the preferred embodiments.
Obviously, modifications and alterations will occur to others upon reading and
understanding the preceding detailed description. It is intended that the
invention be construed as including all such modifications and alterations
insofar as they come within the scope of the appended claims or the equivalents
thereof.
What is claimed is:
1. An aqueous dispersion of microcapsules wherein the microcapsules comprise:
a . at least one hydrophobic substance; and
b. a proteinaceous interface surrounding the at least one hydrophobic substance,
wherein the proteinaceous interface comprises a polysaccharide glycated protein, and
wherein the polysaccharide glycated protein comprises at least one protein residue and
at least one high molecular weight polysaccharide residue.
2. The aqueous dispersion of claim 1wherein the microcapsule consists essentially of:
a . at least one hydrophobic substance; and
b. a proteinaceous interface surrounding the at least one hydrophobic substance,
wherein the proteinaceous interface consists essentially of a polysaccharide glycated
protein, and
wherein the polysaccharide glycated protein consists essentially of at least one protein
residue and at least one polysaccharide residue.
3. The aqueous dispersion of claim 1, wherein the at least one polysaccharide residue
has a molecular weight of at least 5 kDa.
4. The aqueous dispersion of claim 1, wherein the at least one polysaccharide residue
has a molecular weight of at least 200 kDa.
5. The aqueous dispersion of claim 1, wherein the at least one polysaccharide residue is
selected from pullulan residue, dextran residue, guar gum residue, locust bean gum
residue, tara gum residue, pectin residue, and combinations of any of them.
6. The aqueous dispersion of claim 1, wherein the at least one protein residue is selected
from whey protein residue, ovalbumine residue, lysozym residue, potato protein
residue, soy protein residue, zein residue, gluten residue, and combinations of any of
them.
7. The aqueous dispersion of claim 1, wherein the at least one hydrophobic substance is
selected from lipids, water-insoluble vitamins, water-insoluble sterols, water-insoluble
flavonoids, flavors, essential oils, and combinations of any of them.
8. The aqueous dispersion of claim 1, wherein the at least one protein residue comprises
a whey protein residue and the at least one polysaccharide residue comprises a
pullulan residue.
9. The aqueous dispersion of claim 1, wherein the microcapsules have a volume
weighted average diameter in the range of 0.1-500 mih.
10. The aqueous dispersion of claim 1, wherein the at least one hydrophobic substance is
an oil droplet.
11. The aqueous dispersion of claim 10, wherein the oil droplet has a mean diameter in
the range of 0.01-20 mih.
12. The aqueous dispersion of claim 1, wherein the proteinaceous interface further
comprises at least one second protein and at least one second polysaccharide.
13. The aqueous dispersion of claim 12, wherein the proteinaceous interface has a dry
weight composition of:
a . 0.25-30 wt.% polysaccharide glycated protein;
b. 20-97.5 wt.% second protein; and
c . 0-50 wt .% second polysaccharide.
14. The aqueous dispersion of claim 13, wherein the polysaccharide glycated protein, the
second protein, and the second polysaccharide represent at least 80 wt.%> of the dry
weight composition of the proteinaceous interface.
15. The aqueous dispersion of claim 1, wherein the proteinaceous interface has a mean
thickness of 0.005-10 m.
16. The aqueous dispersion of claim 1, wherein the proteinaceous interface further
comprises at least one pectin.
17. The aqueous dispersion of claim 16, wherein the pectin comprises at least 0.5 wt.% of
the dry weight composition of the proteinaceous interface.
18. The aqueous dispersion of claim 16, wherein the at least one pectin is selected from a
high ester pectin, a low ester pectin, an amidated pectin and combinations of any of
them.
19. The aqueous dispersion of claim 16, wherein the at least one pectin comprises a high
methyl ester pectin.
20. The aqueous dispersion of claim 16, wherein the at least one pectin comprises a citrus
pectin.
21. The aqueous dispersion of claim 1, wherein the at least one hydrophobic substance
comprises at least 5 wt% of the microcapsule.
22. The aqueous dispersion of claim 1, wherein the at least one hydrophobic substance
comprises an oil containing a polyunsaturated fatty acid.
23. The aqueous dispersion of claim 1, wherein the at least one hydrophobic substance
comprises an oil containing a polyunsaturated fatty acid selected from an omega-3
fatty acid, an omega-6 fatty acid, or a combination of any of them.
The aqueous dispersion of claim 1, wherein the at least one hydrophobic substances
comprises an oil containing docosahexaenoic acid (DHA), eicosapentaenoic acid
(EPA), steradonic acid, a-Linolenic acid (ALA), conjugated linoleic acid (CLA), or a
combination of any of them.
25. The aqueous dispersion of claim 1, wherein the at least one polysaccharide residue
comprises pullulan residue, the at least one protein residue comprises whey protein
residue, and the at least one hydrophobic substance comprises omega-3 fatty acid.
26. The aqueous dispersion of claim 25, further comprising pectin.
27. A food product comprising the aqueous dispersion of microcapsules of claim 1.
28. The food product of claim 27, wherein the food product is a beverage.
29. The food product of claim 27, wherein the food product has a pH of 1.0 to 7.0.
30. A method for forming an aqueous dispersion of microcapsules comprising:
a . preparing a solution of a protein and a polysaccharide;
b. freeze drying the solution of the protein and the polysaccharide to form a
freeze dried product;
c . heating the freeze dried product comprising the protein and the polysaccharide
to form polysaccharide glycated protein;
d. combining and homogenizing water, a hydrophobic substance, and the
polysaccharide glycated protein into an emulsion with the polysaccharide
glycated protein accumulating at the interface of the hydrophobic substance
and the water, thereby producing an aqueous dispersion of microcapsules.
31. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the solution of the protein and the polysaccharide comprises 10-20 wt.% of the protein
and 10-25 wt.% of the polysaccharide.
32. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the solution of the protein and the polysaccharide is subject to high shear mixing for
10 min, at 5000 rpm using a table top mixer.
33. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the solution of the protein and the polysaccharide is freeze dried.
34. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the freeze dried product is heated at 40-60° C, at 40-80% relative humidity, for 24-48
hours.
35. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the emulsion of polysaccharide glycated protein, water, and a hydrophobic substance
has a pH of about 6.0 to 7.0.
36. The method for forming an aqueous dispersion of microcapsules of claim 30, wherein
the aqueous dispersion of microcapsules is added to a food product.
37. The method for forming an aqueous dispersion of microcapsules of claim 36, wherein
the food product has a pH of 1.0 to 5.5.
38. A food product comprising microcapsules, wherein the microcapsules comprise:
a . at least one hydrophobic substance; and
b. a layer around the at least one hydrophobic substance,
wherein the layer comprises polysaccharide glycated protein, and
wherein the polysaccharide glycated protein comprises at least one protein residue and
at least one polysaccharide residue.
39. An aqueous dispersion of microcapsules wherein the microcapsules comprise:
a . at least one hydrophobic substance comprising omega-3 fatty acids; and
b. a proteinaceous interface around the at least one hydrophobic substance,
wherein the proteinaceous interface comprises polysaccharide glycated protein,
wherein the polysaccharide glycated protein comprises at least one whey protein
residue and at least one pullulan residue, and
wherein the proteinaceous interface has a mean thickness of 0.005-10.0 mih.