Note: Descriptions are shown in the official language in which they were submitted.
130Zl~'~
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EDIBLE BODY AND PROCESS FOR
PREPARATION THEREOF
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates to an edible
body comprising a cellulose having a crystal form of
cellulose II and at least one component selected from
polypeptides and edible polysaccharides, and a process
for the preparation thereof. This edible body has
various functions and is used especially in the fields
of food and agriculture.
(2) Description of the Related Art
Various researches and studies have been made
into the formation of films and fibers from poly-
peptides, edible saccharides, and living body con-
stituents containing these as main components. Most,
however, have ended in industrial failure. The main
reason for this is that the starting materials are
expensive and the yields of final molded bodies are low,
and products having a sufficient mechanical strength are
difficult to obtain. As the rare instances of success,
in connection with polypeptides, there can be mentioned
the utilization of collagen as a casing film for
packaging sausage and the formation of dried bean curds
from soybeans. A separated soybean protein has been
used as a fibrous protein and added to various fish
meats and processed meat products. These products,
however, have an insufficient mechanical strength, and
satisfactory elasticity, strength and elongation charac-
teristics are not manifested.
In connection with edible polysaccharides,
various uses of pullulan films have been developed, and
as is well known, starch is marketed as a medicine
wrapping wafer, oblaat. However, it has been difficult
to prepare products having a high mechanical strength
13gl X~
-- 2 --
from these alone. For example, an oblaat film is
heterogeneous and has a poor strength, and even in the
presence of a very small amount of moisture, the shape
cannot be maintained and the oblaat film cannot properly
function as an edible packing material.
To overcome some of these defects, trials have
been carried out of adding a cellulose fiber or powder
to the above-mentioned polypeptide or edible poly-
saccharide while the dietary property thereof is noted.
lQ For example, Japanese Unexamined Patent Publication
No. 51-70873 teaches a process in which a granular
cellulose and a protein are mixed by a special method.
Furthermore, Japanese Unexamined Patent Publication
No. 48-39670 discloses a process in which a chewing gum
base is prepared by mixing gluten with granular
cellulose. As is well known, a cellulose has an
excellent dimensional stability as a regenerated
fiber or cellophane, and is used as a starting material
for the formation of a product having a satisfactory
mechanical strength. But, by adding a fine powder or
fine fiber of a cellulose only to the above-mentioned
polypeptide or edible polysaccharide, the cellulose
component is dispersed as an island component in the
polypeptide or edible polysaccharide, and therefore, a
prominent improvement of the mechanical strength cannot
be expected. When a fine powder or fine fiber of a
cellulose is used at too high a content, since the
mixture maintains a solid structure inherently possessed
by the cellulose, an incompatible taste is given, and in
some cases, the cellulose has a bitter taste which
remains in the mouth.
As means for improving the mechanical strength
of an edible body of the above-mentioned polypeptide or
edible polysaccharide by using a cellulose, there may be
considered a process in which the cellulose is once
dissolved, the desired substance is incorporated in the
solution, and the cellulose is regenerated. Although
13~2~ '7
~J
-- 3
attainment of this object is not intended, Japanese
Patent Publication No. 51-55355 of May 15, 1976,
discloses a process in which in order to obtain a cheap
regenerated cullulose film, modified starch is added to a
cuprammonium solution or viscose solution of a cellulose.
However, incorporation of toxic substances such as by-
products derived from a copper ion or carbon disulfide
are present in the product describèd in this publication,
and therefore, this process cannot be utilized in the
field of food.
We carried out research with a view to overcoming
the defects of the above-mentioned polypeptide or edible
polysaccharide, that is, (1) brittleness and poor
mechanical strength, and (2) a high cost of the starting
material, by utilizing a cellulose, and also to
overcoming the defects of the cellulose, that is, an
incompatible taste remaining in the mouth, by changing
the mixed or dispersed state in the polypeptide or edible
polysaccharide.
SUMMARY OF THE INVENTION
Under this background, we carried out research, and
as a result, it was found that if a cellulose soluble in
a solution of an alkali such as caustic soda and a
polypeptide, an edible polysaccharide or a living body
constitutent are mix-dissolved or mix-dispersed to form a
dope, and this dope is coagulated, as disclosed in
Japanese Unexamined Patent Publications No. 60-42401 and
No. 60-42438, and Japanese Patent Application No. 60-
27544, published on March 6, 1985; March 6, 1985; and
February 12, 1985, respectively, an edible body having a
special dispersion state can be obtained.
This edible body has no toxicity but is different
from the conventional composition comprising a cellulose
dispersed in a polypeptide or polysaccharide in that,
even if the ~ellulose composition comprising a cellulose
,
.
13l~ '7
- 3~ -
dispersed in a polypeptide or polysaccharide in that,
even if the cellulose content is high, no incompatible
taste is given on eating and the cellulose does not
remain in the mouth. ~his edible body has excellent
mechanical strengths, good water-absorbing property, and
~r~
13~ 7
superior wet processability.
In accordance with the present invention, there is
provided an edible body consisting essentially of a
structural body comprising a cellulose having a crystal
form of cellulose II, which is regenerated from an
aqueous solution of an alkali metal hydroxide, and at
least one guest component selected from polypeptides and
edible polysaccharides, wherein the cellulose II or a
homogeneous mixture of the cellulose II and poly-
saccharide is present in the form of a sea component ora continuous phase in an amount of at least 10% based on
the structural body.
By the term "sea component" is meant a phase
distributed in the state surrounding another phase, when
the section of the structural member is observed by a
transmission type electron microscope or optical
microscope, and by the term "continuous phase" is meant
a phase continuously distributed, which may contain
voids.
By the passage "in the form of a sea component or a
continuous phase in an amount of at least 10% based on
the structural body", we mean that, in the edible body
which is composed of the sea and islands, when a cross-
section of the edible body is observed by a microscope
at a magnification such that at least five islands are
found in the field of view, the proportion of the area
of the sea to the total area of the field of view is at
least 10%. In the edible body wherein the sea and
islands are not found, when a cross-section thereof is
observed in a similar manner, the proportion of the area
of the continuous phase to the total area of the field
of view is at least 10~.
The above-mentioned edible body is prepared
according to a process comprising adding at least one
component selected from polypeptides, polysaccharides,
and living body constituents composed mainly thereof, to
an alkali solution in which up to 50 parts by weight of
13~2~
an undissolved cellulose is swollen and dispersed per 100
parts by weight of a dissolved cellulose, directly or
after dissolution in an aqueous solution of an alkali, to
form a dope in which at least 50% by weight of the total
guest component is dissolved, extruding the dope through
an extruder, coagulating the extrudate, and neutralizing,
water-washing and, if necessary, drying the extrudate.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure l-A shows a solid CP/MASl3C-NMR spectrum
of the Cl-to-C~ carbon peak region of natural cellulose;
Fig. l-B shows a solid CP/MASl3C-NMR spectrum of
the C4 carbon peak region of regenerated cellulose;
Fig. 2 is a diagram illustrating an apparatus
for the deuteration IR method;
Fig. 3 shows an infrared absorption spectrum
after the deuteration (equilibration), which is used for
the calculation of the ratio (Hb) of the optical density
at 3430 cm~l to the optical density at 3360 cm~l at the time
of theequilibrium deuteration;
Fig. 4 is a transmission electron micrograph of
a section through an edible structural body according to
the invention, illustration islands in a surrounding "sea
component" phase;
Fig. 5 is a transmission electron micrograph of
a section through an edible structural body according to
the invention illustrating the presence of voids in a
continuous phase;
Figs. 6 to 8 are transmission electron
micrographs of an ultra-thin slice through an edible body
prepared according to Example 1 below, showing an island-
in-sea structure with the island component ranging in size
from 0.2 ~m to 200 ~m; and
Fig. 9 is an optical microscopic photograph of a
dyed film prepared according to Comparative Example 1
below.
~3~.'Z~ ~
- 5a -
DESCRIPTION OF THE PREFERRED EMBODIMENTS
By the term "edible body" used in the instant
specification is meant a structural body in which a paper-
like taste inherent to cellulose is controlled and which
can be eaten by humans.
As the cellulose that is used as the starting
material in the present invention, there can be mentioned
a natural cellulose in which the intramolecular halogen
bond degree Hb (3+6) at the C3 and C6 positions, which is
defined by the CP/MAS 13C-NMR measurement, is not more
than 60%, and a regenerated cellulose in which the
intramolecular hydrogen bond degree Hb (3) at the C3
position is not more than 30%. Preferably, the
solubility, defined hereinafter, of the cellulose is at
least 67%. A natural cellulose in which the
intramolecular hydrogen bond degree Hb (3+6) is 0 to 48%
and ....................................................
13~Zi~JY
-- 6 --
a regenerated cellulose in which the intramolecular
hydrogen bond degree Hb ~3) at the C3 position is 0 to
15~ and the solubility is almost 100~ are especially
preferable. If such a cellulose is used, mixing with a
polypeptide and/or an edible polysaccharide, defined in
the present invention, can be guaranteed and a higher
mechanical strength can be realized in the obtained
edible body. Since the presence of an undissolved
cellulose is allowed in the edible body of the present
invention, a cellulose other than those mentioned above
may be used in combination with the above-mentioned
cellulose. However, if the content of the undissolved
cellulose is higher than 50~ by weight based on the
cellulose dissolved in the dope prepared in the process
for preparing the edible body of the present invention,
an edible body having sufficient mechanical strength
cannot be obtained.
The method for determining 13C-NMR referred to in
the instant specification and the method for determining
the degrees Hb (3+6) and Hb (3) will now be described.
A solid high-resolution 13C-NMR spectrum is measured
according to the CP/MAS (cross-polarization magic angle
spinning) method using a pulse-Fourier conversion type
NMR spectrometer. A sample is packed in a Teflon sample
tube. The contact time is about 2 milliseconds, and the
sample rotation number is at least 3000 Hz. The measure-
ment is carried out when the sample is in the air-dried
state or the wet state. The chemical shift of each peak
is determined on the basis of the preposition that the
value of the methyl peak of admantane determined under
the same conditions as described above is 29.5 ppm. The
measurement is carried out at a temperature ranging from
room temperature to 60C. Pulses are integrated more
than 500 times.
Figure l-A shows the solid CP/MAS C-NMR spectrum
of the Cl-to-C6 carbon peak region of natural
cellulose, and Fig. l-B shows the CP/MAS 3C-NMR
13~
-- 7
spectrum of the C4 carbon peak of regenerated cellulose.
The degrees Hb (3+6~ and Hb (3) defined above are
proportions of unhatched regions (low-magnetic field
regions) of the C4 carbon peak and the C4 and C6 carbon
peaks, and are ordinarily determined from an integrated
curve of the spectrum. Referring to the drawings, the
degree Hb (3+63 applied to natural cellulose is expressed
by the area ratio ~(a+b)/(a+b+c+d)~ x 100 (%). In the
cellulose shown in Fig. l-A, the degree Hb (3+6) i5 45%.
The degree Hb (3) applied to regenerated cellulose is
expressed by the area ratio ~a/(a+b)~ x 100 (%) in
Fig. l-B. In Fig. l-B, (i) through (iv) indicate
celluloses differing in the degrees Hb (3), and having
the degrees Hb (3) of 44%, 38%, 21%, and 13%, respec-
tively. Furthermore, a and c are area ratios of theunhatched portions (low-magnetic field regions) of the
C4 and C6 carbon peaks, and are ordinarily determined
from the integrated curve of the spectrum. On the other
hand, b and d are area ratios of the hatched regions
(high-magnetic field regions) of the C4 and C6 carbon
peaks.
The natural cellulose in which the intramolecular
hydrogen bond degree at the C3 and C6 positions is not
more than 60% is obtained by adjusting the polymerization
degree of a natural cellulose such as wood pulp, cotton
or flax by the acid hydrolysis, or by subjecting a
natural cellulose to a mechanical pulverization
treatment, a blasting treatment, an extruder treatment
at a high temperature or a treatment with an enzyme
solution. A regenerated cellulose in which the intra-
molecular hydrogen bond degree is not more than 30% is
obtained by dissolving a cellulose in a solvent and
performing neutralization regeneration or coagulation or
evaporating an easily-volatile solvent component to
effect coagulation and regeneration.
A preferred cellulose having a high alkali
solubility, that is, a natural cellulose having an Hb
13~. 2~g~7
(3+6) value of 0 to 48% or a regenerated cellulose
having an Hb (3) value of 0 to 15~, is prepared by
subjecting a natural cellulose having the polymerization
degree, defined hereinafter, adjusted below 700, such as
wood pulp, cotton or flax, to a blasting or extruder
treatment from the high-temperature and high-pressure
state in the presence of a hydrogen bond cleaving agent,
treating such a natural cellulose with an enzyme solution
or dissolving such a natural cellulose in a solvent,
neutralizing and regenerating the cellulose or coagu-
lating the cellulose in a non-solvent, or evaporating an
easily-volatile solvent component to effect coagulation
and regeneration. In view of the attainment of a very
high alkali solubility, a regenerated cellulose obtained
by dissolving a cellulose in a cuprammonium solution,
evaporating the ammonia component, solidifying the
residue and neutralizing and regenerating the solid with
an acid solution is most preferable. However, if a
salient amount of copper remains in the resulting edible
body, the copper is poisonous. Therefore, the regener-
ated product is washed repeatedly so that the amount of
copper is reduced below 10 ppm. As the hydrogen bond
cleaving agent, there can be mentioned solvents for
celluloses, such as water, an aqueous solution of an
alkali, an aqueous solution of an acid, and an aqueous
solution of a salt.
The solubility referred to in the instant specifi-
cation is determined as follows. Namely, the cellulose
is dissolved at a concentration of 5% by weight in an
aqueous solution containing 9.1% by weight of sodium
hydroxide at a temperature of 5C, and the undissolved
portion is centrifugally separated at a rotation number
of 7000 rpm and the cellulose is neutralized and
regenerated. Then, the cellulose is weighed. The
solubility is determined from the obtained value and the
initially charged amount of the cellulose.
The polymerization degree is not particularly
~3(3 2~7
g
critical, but in the case of a natural cellulose having
an Hb (3+6) value of 0 to 48% or a regenerated cellulose
having an Hb (3+6) value of 0 to 15~, in view of the
preparation process, it is difficult to obtain a
cellulose having a polymerization degree higher
than 1200. In order to obtain a final edible body
having a high mechanical strength, it is sufficient if
the polymerization degree of the alkali-soluble cellulose
is not lower than 100. If the polymerization degree is
lower than 100, a reinforcing effect cannot be attained
by utilization of the cellulose. The polymerization
degree referred to in the instant specification is
determined according to the following method.
The viscosity average polymerization degree
determined from the viscosity of a cadoxene solution.
More specifically, in 2414 g of distilled water is
gradually incorporated 900 g of ethylenediamine of the
guaranteed reagent while maintaining the liquid mixture
at 0C. Then, 318 g of cadmium oxide of the guaranteed
reagent is gradually added over a period of 2 to 3 hours
while stirring the liquid mixture at 0C. The mixture
is allowed to stand overnight at -15C, and 60 ml of
ethylenediamine, 155 ml of distilled water and 14 g of
caustic soda are added to 950 ml of the supernatant to
form a starting cadoxane solution. The weighed cellulose
is dissolved in the starting cadoxene solution maintained
below 6C, and the solution is diluted with distilled
water in the same amount as that of the starting cadoxene
solution. The concentration (g/dl) of the solution is
designated as c. The falling time t (seconds) of the
cellulose/cadoxene solution and the falling time to
(seconds) of the cadoxene solution diluted at a ratio of
2 are measured at 25C by a Ubbellohde viscometer in
which the falling time of the water is about 80 to about
120 seconds at 20C. The viscosity average molecular
weight Mv is calculated by substituting the inherent
viscosity defined by the formula
~3~Z1~7 `
-- 10 --
~n J= lim [(t/to - l)/c)
into the viscosity formula (n) = 3.85 x 10 Mv 6
of Brown-Wikstrom (Euro. Polym. J., 1, 1, 1966). The
obtained value is divided by 162 to determine the
viscosity average polymerization degree. By using the
empirical rule of the concentration dependency of the
viscosity, the inherent viscosity may be determined as a
solution of the following equation from the value of the
falling time at one concentration point:
ck[n) --~-- !nl - v = n
wherein v = (t/to - l)/c and k = n.n33~l~7 ~
As the polypeptide used as the guest component,
there can be mentioned soybean proteins purified v
various methods, casein, albumin, globulin and gelatinp
and Na, Ca and K salts thereof. These polypeptides may
be partially hydrolyzed. Each of them is soluble or
substantially soluble in a dilute aqueous solution of an
alkali. In view of mixing with the cellulose solution
and improvement of the mechanical properties of the
obtained edible body, a polypeptide which is completely
soluble in a dilute aqueous solution of an alkali is
preferred.
As the edible polysaccharide used in the present
invention, there can be mentioned gum arabic, arabino
galactan, alginic acid, gum ghatti, carrageenin, karaya
gum, xanthane gum, guar gum, devil's-tongue powder,
tamarind gum, tala gum, tragacanth gum, furcellaran,
pullulane, pectin, chitin, locust bean gum, xylan,
mannan and starches (corn starch, amylose-rich starch,
potato starch and rice starch), and salts thereof, such
as Na, K and Ca salts. All of these edible poly-
saccharides except chitin are completely soluble in
water or a dilute aqueous solution of an alkali.
Accordingly, a molded edible body of a mixture of such a
polysaccharide with a cellulose has particularly
excellent mechanical characteristics.
,,
~3~2i~-~7
-- 11 --
The polypeptide and polysaccharide used in the
present invention may be in the form of a living body
constituent. By the living body constituent is meant a
living body constituent containing one or both of a
polypeptide and polysaccharide derived from a plant, an
animal or a microorganism, preferably a living body
constituent containing the polypeptide and/or poly-
saccharide in an amount of at least 50% based on the
total solid except water. As typical examples of the
living body constituent derived from a plant, there can
be mentioned oil cakes, grains, beans, plant stalks and
leaves, algae, fruits and tuberous roots. More specif-
ically, there can be mentioned defatted soybean, soybean
meal, baked soybean flour, linseed oil cake, cotton seed
oil cake, coconut oil cake, sufflower oil cake, sesame
oil cake, sun flower oil cake, wheat, barley, rice and
soybean (whole fat soybean). As examples of the con-
stituent derived from an animal, there can be mentioned
fish meal, fish soluble, meat flour, meat bone powder,
decomposed hair, decomposed leather, feather meal, skim
milk powder, fish meat, meat (beef, pork, mutton or the
like), entrails, egg constituents (york and albumen),
krill, and milk constituents. As examples of the living
body constituent derived from a microorganism, there can
be mentioned yeasts, bacteria, and molds. These living
body constituents comprise proteins and/or poly-
saccharides as the main component and also contain
impurities such as lipids, nucleic acids, lignins and
inorganic salts. If such impurities are contained,
mixing with the cellulose solution is not hindered, but
the spinnability or stringiness is improved and
appropriate fusion bonding is advantageously attained
among spun fibers.
The guest component to be mixed with the cellulose,
which is selected from polypeptides, edible poly-
saccharides and living body constituents, need not be
composed of a single substance but may be a mixture of
13~ 7
- 12 -
two or more of the foregoing substances.
In the edible body of the present invention,
cellulose II or a homogeneous mixture of cellulose II
and the edible polysaccharide (where the polysaccharide
is used) is present as the sea component or continuous
phase in an amount of at least 10~.
When the section of the edible structural body is
observed by a transmission electron microscope or an
optical microscope, if a certain phase is distributed in
the state surrounding another phase, for example, the
sea phase (A) surrounds islands ~D) as shown in the
photo of Fig. 4, the surrounding phase is called a "sea
component". When the microscopic observation is
similarly made, if a certain phase (C) is continuous
even though voids (B) are present, as shown in the photo
of Fig. 5, this phase is called a "continuous phase".
A transmission microscope is mainly used for the
observation of the section, but where the sea component
covers a broad region, an optical microscope can be
used.
By the term "homogeneous mixture" is meant a
constituent which can be regarded as one phase even if
small specks are seen.
In order that the fiber or film retains its shape
and an appropriate mechanical strength is manifested, it
is important that the sea component or the continuous
phase be present in an amount of at least 10~. When a
high strength is especially required for the fiber or
film, for example, where the molded body is used in the
field of castings, preferably the sea component or
continuous phase is present in an amount of 80 to 90~ or
larger.
In the case of an ordinary edible body comprising a
cellulose and an edible polysaccharide, both the com-
ponents are present in the form of a homogeneous con-
tinuous phase. In the case of an edible body comprising
a cellulose and a polypeptide, the cellulose is present
-` 13~21~7
- 13 -
in the form of a sea component surrounding the islands
of the polypeptide.
For example, when an edible body of the present
invention comprising a cellulose and a separated soybean
protein is observed by a transmission electron micro-
scope, the size in the section of the island component
differs according to the preparation process, but is
ordinarily in the range of from 0.05 ~m to 100 ~m. In
view of the feeling at the time of eating, preferably
the size of the island component is within the above-
mentioned range. The shape of the island component is
ordinarily circular or ellipsoidal.
The observation using a transmission electron
microscope is carried out in the following manner. A
sample yarn in the wet state is dehydrated with methanol
and substituted with a methacrylate resin, the yarn is
embedded in the methacrylate resin, and an ultra-thin
section having a thickness of 0.1 ~m is prepared by
using an ultramicrotome supplied by LKB Co. The sliced
resin is dissolved in chloroform and soluble ingredients
are removed. The section is observed at an acceleration
voltage of 80 kV at 2000 to 6000 magnifications by using
a transmission electron microscope (Model JEM1200EX
supplied by Nippon Denshi). In the case of observation
using an optical microscope, a slice having a thickness
of about 0.3 ~m is similarly prepared. The resin is
dissolved out by using chloroform, and a sample yarn
containing polypeptide is dyed with Alizarine Blue to
stain the polypeptide, or a sample yarn containing
polysaccharide is dyed with an iodine solution to stain
the polysaccharide. The observation is carried out at
100 to 400 magnifications. By the term "section"
referred to herein is meant a section perpendicular to
the extrusion direction in the case of an extrusion-
molded body such as a yarn or film, and meant an optionalsection in the case of a powder or sphere.
In the edible molded body of the present invention,
~3~Z1~7
- 14 -
the strength can be maintained if the cellulose content
is at least 5% by weight based on the dry product,
though this value differs to some extent according to
the kinds of edible polysaccharide and polypeptide.
Nevertheless, this cellulose content should be determined
while taking the intended use of the final molded body
and the preparation characteristics into consideration.
In connection with utilization in the field of food, for
example, in case of an edible film or fabricated food
products, preferably the polypeptide and/or poly-
saccharide (the edible polysaccharide and/or polypeptide
will be called "guest component" hereinafter) is con-
tained in an amount of at least 10% by weight, more
preferably at least 40% by weight in the edible body of
the present invention. In order that the edible body of
the present invention does not give an incompatible
taste on eating and does not remain in the mouth, the
cellulose/guest component weight ratio is preferably in
the range of from 5/95 to 90/10 and more preferably in
the range of from 10/90 to 60/40. Where a polypeptide,
edible polysaccharide and/or living body constituent is
mixed with a powder or fine fiber of the cellulose in
the solid state, if the cellulose content exceeds 10%,
the mixture cannot be eaten at all because it remains in
the mouth and has bitter taste. In view of this, it
will be readily understood that the edible body of the
present invention is excellent. In view of the rein-
forcing effect by the cellulose, preferably the mixing
ratio of the guest component in the mixture is up to 95
by weight. When the cellulose content is extremely low,
even if a cellulose having a high polymerization degree
is used, the mechanical strength is little improved in a
molded product of the edible body of the present in-
vention. Preferably, the cellulose content is at least
5% by weight.
The molded product of the edible body of the
present invention can be prepared according to the
13~2i47
- 15 -
following procedures. At first, a mixed dope of the
cellulose and the guest component is preparQd. For this
purpose, there may be adopted (l) a method in which the
cellulose specified in the present invention is com-
pletely or partially dissolved in an aqueous solution ofan alkali having a specific concentration, the guest
component is supplied in the powdery or solid state to
the solution, and the guest component is dissolved or
dispersed in the solution, and (2) a method in which
both the cellulose and the guest component are in-
dependently dissolved in appropriate alkaline aqueous
solutions and the solutions are mixed.
In the former method (l), the alkali is used in the
form of an aqueous solution having a normality (herein-
after referred to as "N") of 2.0 to 2.5 for dissolutionof the cellulose. The cellulose is dissolved in this
aqueous solution at a temperature of from -10C to 10C.
Otherwise, the dissolution of the cellulose is not
completed, or even if completed, the solution is soon
gelled, and the solution is not suitable for the sub-
sequent mixing or spinning operation. The once-formed
cellulose solution may be diluted with water according
to the cellulose concentration, and this solution can be
used for the dissolution or dispersion of the guest
component. In the latter method (2), the cellulose is
dissolved in the alkali solution according to the above
procedures.
The guest component such as the polypeptide, edible
polysaccharide and/or living body constituent is
preferably dissolved in an aqueous solution of an alkali
metal hydroxide. The temperature may be elevated to
about 50C for the dissolution. The alkali concen-
tration is 0.5 to 3.0 N. Although the upper limit of
the alkali concentration in the alkaline solution is not
particularly critical, since in the case of the poly-
peptide the main chain is readily decomposed if an
aqueous solution having too high an alkali concentration
13~Z1~7
- 16 -
is used, the upper limit is preferably set at the alkali
concentration in the alkaline aqueous solution used for
the dissolution of the cellulose. Note, it was found
that, if a dissolved cellulose is present in a poly-
peptide solution, the decomposition of the polypeptideby an alkali is extremely delayed. This is an important
functional effect of the present invention. If the
alkali concentration is lower than 0.5 N, the guest
component cannot be sufficiently dissolved. In the
latter method (2), the alkali concentration in the
solution of the cellulose need not be the same as the
alkali concentration in the solution of the guest
component, and these concentrations may be appropriately
set while taking the mixing state and the advance of
gelation into consideration.
As specific examples of the alkaline solvent used
for formation of the dope, there can be mentioned
aqueous solutions of hydroxides of alkali metals such as
sodium. When the finally obtained molded body is used
in the field of medicines or food, such an alkali metal
hydroxide is preferred from the viewpoint of the safety,
and this is one of advantages attained by the present
invention.
When a molded edible body is prepared from this
dope according to the method described hereinafter, the
dissolved cellulose is generally regenexated to a
cellulose having a crystal form of cellulose II, and a
mechanical strength is manifested in the molded edible
body. In view of the mechanical strength of the molded
edible body, preferably the cellulose is completely
dissolved in the preparation of the dope. In this case,
a natural cellulose having an intramolecular hydrogen
bond degree Hb (3+6~ of 0 to 48% or a regenerated
cellulose having an intramolecular hydrogen bond degree
Hb (3) of 0 to 15~, the alkali solubility of which is
substantially 100%, is used. However, in some cases,
preferably an insoluble cellulose in the form of a fine
-' 13~Zif~7
- 17 -
fiber is present in the mixture. In this case, it is
possible to use a dope in which a cellulose other than
the alkali-dissolved cellulose specified in the present
invention is present in an amount of up to 50 parts by
weight per 100 parts by weight of the alkali-dissolved
cellulose in the alkaline dope of the cellulose and
guest component. If the amount of the undissolved
cellulose exceeds 50 parts by weight, a sufficient
mechanical strength cannot be guaranteed for the final
molded body. Accordingly, specifically speaking, a
natural cellulose having a value Hb (3~6) of 49 to 60%
or a regenerated cellulose having a value Hb (3) of 15
to 30%, the alkali solubility of which is 67 to 90%, is
used as the cellulose. In the case of this cellulose,
the mixing amount should be adjusted so that the amount
of the insoluble cellulose does not exceed the above-
mentioned upper limit. This doe also can be prepared
according to a method in which an alkali solution of a
natural cellulose having a value Hb (3+6) of 0 to 48% or
a regenerated cellulose having a value Hb (3) of 0 to
15% or an alkali dope formed by incorporating and
dissolving the guest component in this alkali solution
is mixed with a cellulose dispersion formed by swelling
and dispersing a cellulose in an aqueous solution of an
alkali having a normality smaller than 2. Almost all
celluloses are merely swollen or dispersed in an aqueous
solution of an alkali having a normality smaller than 2,
preferably smaller than 1.5.
The above-mentioned alkali dope comprising the
cellulose and guest component may further comprise a
third component such as a diol, a polyol, an oil or fat,
a seasoning, a pigment or a perfume, according to need.
A molded product of the edible body of the present
invention can be prepared by extruding the above-
mentioned dope directly into an acidic bath or a salt-
containing acidic bath by using an ordinary extruder and
molding the extrudate while performing coagulation and
~3~3`2147
- 18 -
neutralization, followed by water washing and drying, if
necessary thereinafter referred to as "process A").
According to another process, the above-mentioned
dopes is extruded in water or an aqueous solution of a
neutral salt, and the extrudate is coagulated and passed
through an acidic aqueous solution to effect
neutralization, followed by water washing and drying, if
necessary (hereinafter referred to as "process B").
In each of the foregoing processes A and B, if the
extrudate is drawn at a draw ration of 1.1 to 1.6 at any
of the coagulation, neutralization and drying steps,
there can be obtained a molded body, such as a fiber or
film, having an excellent mechanical strength.
When a powder or granule is prepared, the intended
product can be obtained merely by stirring the extruded
dope at the coagulation or neutralization step.
After the water washing in the above-mentioned
processes, the edible body can be impregnated with an
aliphatic alcohol or an oil or fat, or a solùtion or
dispersion of the alcohol or oil or fat in water.
Usually, the aliphatic alcohol-impregnated edible body
has a good pliability and elasticity, and the oil- or
fat-impregnated edible body has a good water repellency,
water resistance and transparency.
The edible body comprising the cellulose and guest
component often contains 10 to 1200 parts by weight of
water per 100 parts by weight of the dry edible body.
If water is contained in an amount of several hundred
parts, when the edible body is used as a food additive
or for the production of an artificial meet, mixing of
the edible body with other ingredients can be
facilitated, and since this edible body is prepared by
the wet process, an energy-consuming step such as
drying, for the removal of water, can be omitted.
13~Zl~'o
As the acid used at the coagulation and neutral-
ization steps of the preparation process of the present
invention, there can be mentioned nitric acid, sulfuric
acid, hydrochloric acid, acetic acid and phosphoric
acid, and the acid is used in the state dissolved in
water or an organic solvent. The acid concentration is
not particularly critical ~ut is appropriately selected
from the economical viewpoint.
As the salt used at the present step, there is
preferably used an alkali metal or alkaline earth metal
salt of nitric acid, sulfuric acid, hydrochloric acid,
. ~,
- ~.3~Z1~7
- 19 -
acetic acid or phosphoric acid. This salt may be used
in combination with the above-mentioned acid. The
concentration of the salt in the coagulating bath is
from 0~ to the saturation concentration. As the organic
solvent, preferably an alcohol, a ketone, an amide or a
sulfoxide is used, and from the economical viewpoint, an
alcohol is especially preferred. When an alcohol is
used, flowing of the guest component into the coagulating
bath can be prevented, and the intramolecular hydrogen
bond degree of the cellulose portion of the obtained
edible body can be drastically reduced and the edibility
and processability in the wet state of the edible body
are preferably improved. The temperature of the
coagulating bath is in the range of the freezing point
of the used bath to 80C. If the bath temperature is
higher than 80~C, thermal decomposition of the edible
body occurs. In most cases, the lower the bath tem-
perature, the higher the mechanical strength of the
edible body, although the temperature of the coagulating
bath is not particularly critical. The obtained molded
edible body can be finely cut and fed to the step for
forming a final product. Generally, the molded
edible body contains 10 to 1200 parts by weight of water
per 100 parts by weight of the dry edible body.
The edible body prepared according to the process A
is characterized in that, for example, in the case of
the cellulose/starch edible body, if the edible body is
formed into a fiber or film, it shows an elongation of
at least 16~ and about 40% at highest in the wet state.
This is because the intramolecular hydrogen bond degree
in the molecules constituting the edible body is
extremely low. This is obvious from the 13C-NMR
spectrum of the edible body obtained according to the
process A. More specifically, of two envelopes appearing
in the C4 carbon peak region (90.0 to 78.8 ppm) of the
D-glucose units constituting the cellulose and starch
molecules, the proportion of the envelope on the lower
``` 13~21f~7
- 20 -
magnetic field side (the sharp peak component on the
side of the magnetic field lower than about 85.5 ppm) is
low and 8 to 50%, irrespective of the water content, and
this indicates that the intramolecular hydrogen bond
degree is inherently low. This suggests that the edible
body sufficiently retains water in the wet state, and
where the edible body is in the form of a fiber or a
film, the processability in the wet state is excellent.
As pointed out above with respect to the process A,
a film of the edible body can be prepared. For example,
in the case of a 1/1 cellulose starch mixture, when the
obtained film is naturally dried, the non-accessible
content (the proportion of the non-deuterated hydroxyl
group portion) defined by the deuteration IR method
described hereinafter is 32 to 34~, and in the IR
absorption region of the hydroxyl group at the equilib-
rium deuteration, which is attained in the experimental
method defined in the instant specification, the ratio
Hb of the optical density of the peak at 3430 cm 1,
attributed to the intramolecular hydrogen bond, to the
optical density of the peak at 3360 cm 1 is lower
than 1.2. In short, the growth of the intramolecular
hydrogen bond is small.
The experimental deuteration IR method used for
determining a parameter indicating the structure of the
edible body of the present invention comprising the
cellulose and guest component and the method for
determining the non-accessible content will now be
described. The apparatus used is outlined in Fig. 2. A
film of the edible body having a thickness of 10 to
30 ~m is set at a deuteration cell 6. The cell 6 is set
at 70C for removing water and preventing the absorption
of heavy water. The film is allowed to stand for 10
minutes to remove excess water, and the IR spectrum of
the blank (the film of the edible body before the
deuteration) is measured. A dry nitrogen gas at 25C,
which is obtained from a bomb 1 through a drying silica
-`` 13~Z147
- 21 -
gel 2, is fed at a flow rate of 1000 ml/min. Note,
reference numeral 3 represents a flow meter. Heavy
water (20 cc) set at 25C is charged in a heavy water
bubbling vessel 4 and is bubbled by the nitrogen gas,
the bubbled heavy water is introduced into the
deuteration cell 6, and the sample on a sample stand 5
is deuterated. The deuteration is carried out for 120
minutes under this condition, and the IR spectrum is
determined by an IR spectrum device 7.
At first, as shown in Fig. 3, a base line touching
the peaks at 3600 cm 1 and 3000 cm 1 is drawn, and
each of the transmittances at the crossing points of the
vertical lines corresponding to 3430 cm and 3360 cm 1
and the base line is adopted as the intensity Io at
the corresponding wave number. Furthermore, the
intensity I of each of the transmitted lights at
3430 cm 1 and 3360 cm 1 is expressed by the trans-
mittance at the crossing point of the vertical line at
the corresponding wave number and the spectrum. Then,
Hb is determined from Io and I according to the
following formula:
Io
Hb = log 3430 / log 3360
3430 3360
The non-accessible content is calculated according
to the process proposed by J. Mann and H.J. Marrinan in
Trans. Faraday Soc., 52, 492 (1956).
The edible body prepared according to the process B
is characterized in that, for example, in the case of a
cellulose starch mixture, in the 13C-NMR spectrum of the
edible body, of two envelopes appearing in the C4 carbon
peak region (90.0 to 78.8 ppm) of the D-glucose units
constituting the cellulose and guest component, the
proportion of the envelope on the lower magnetic field
side (the sharp peak component on the side of the
magnetic field lower than about 85.5 ppm) is 45 to 65%,
13~2147
- 22 -
irrespective of the water content, and the intramolecular
hydrogen bond degree is inherently high. Accordingly,
where the edible body is in the form of a fiber or a
film, enhanced mechanical characteristics are manifested
5 in either the dry state or the wet state. In the film
of the edible body of the present invention, for example,
in the case of a 1/1 cellulose II/starch mixture, when
the film is naturally dried, the non-accessible content
(the proportion of the non-deuterated hydroxyl group
10 portion) defined by the deuteration IR process is 44 to
47~ and in the IR absorption region attributed to the
hydroxyl group at the equilibrium deuteration, the ratio
Hb of the optical density of the peak at 3430 cm 1,
attributed to the intramolecular hydrogen bond, to the
15 optical density of the peak at 3360 cm 1 is at least 1.2.
In short, the intramolecular hydrogen bond is developed.
The fact that the non-accessible portion shows the
intramolecular hydrogen bond is a criterion indicating a
high structural regularity and guarantees the mani-
20 festation of high mechanical characteristics.
In order to further improve the mechanical charac-
teristics, the orientation degree of the fiber or film
of the edible body prepared by the process A or B may be
further increased. For this purpose, the fiber or film
25 can be drawn in the coagulating bath or may be drawn by
a hot roller or the like before and after water washing.
The drawing temperature is 40 to 200C. If the drawing
temperature is lower than 40C, the effect of the
drawing is not substantially attained, and if the
30 drawing temperature is higher than 200C, there is a
risk of deformation of the final product. A sufficient
improvement of the strength is attained if the draw
ratio is about 1.2. Since the constituent polymer is
oriented, a strength comparable to that of a collagen
film can be obtained, and the edible body can be used
for a casing of a sausage.
The molded edible body of the present invention can
.
,
`` 13~Zlf~7
- 23 -
take various shapes such as the shape of a fiber, a
film, a sphere, a powder, and a granule, and a variety
of structures can be formed from the molded edible body.
Therefore, the edible body of the present invention can
be used in various fields. For example, in connection
with food products, the edible body of the present
invention in the form of a fiber can be used as an
additive or reinforcer to processed fish meat products
such as boiled fish paste, fish meat sausage, and canned
crab, and as an additive or reinforcer to processed
meat products such as sausage, corned beef, and ham.
Furthermore, the fiber of the edible body of the present
invention can be bundled by any method and can be
seasoned and used as an artificial meat or a component
to be mixed with a natural meat. The edible body molded
into a film or sheet can be used as a casing material,
an edible cooking film or a food wrapping film, and a
spherical or granular product of the edible body of the
present invention can be used as a fish egg substitute
such as artificial salmon roe. Moreover, a powdery or
granular product of the edible body of the present
invention can be used as a food additive for attaining
emulsification or as an excipient and can be applied to
the production of ice cream, boiled fish paste, dumpling
stuffed with minced pork, and shao-mai skin. As pointed
out hereinbefore, the edib'e body of the present inven-
tion can be eaten without an incompatible taste even if
the cellulose content is high, and therefore, an anti-
diarrhoic effect possessed by the cellulose can be
sufficiently exerted and the edible body of the present
invention can be applied to the production of medicinal
tablets as well as the above-mentioned food products.
The present invention will now be described in
detail with reference to the following examples that by
no means limit the scope of the invention.
Example 1
A regenerated cellulose nonwoven fabric (Benleese
`` ~3~ 7
- 24 -
supplied by Asahi Kasei Kcgyo K.K.) was sufficiently
washed dried and then dissolved at a concentration of
2.5% by weight in a 2.5 N aqueous solution of sodium
hydroxide, a separated soybean protein (Fuji-Pro R
supplied by Fuji Seiyu) was dissolved in the thus-
prepared solution so that the cellulose/separated
soybean protein dry weight ratio was 5/5, 7/3 or 8/2.
The solution was stirred and mixed by a high-speed
stirrer (supplied by Nippon Seiki). Thus, three homo-
geneous dopes were prepared. Each dope was filteredthrough a 250-mesh screen and extruded at a rate of
45 cc/min from a nozzle having 150 holes, each having a
diameter of 0.25 mm, in a coagulating bath containing 5%
by weight of HCl and 4% by weight of CaC12. The
extrudate was wound at a winding speed of 7 m/min and
washed with water to obtain an edible protein fiber.
An ultra-thin slice was prepared according to the
method described hereinbefore, and the slice was observed
by a transmission electron microscope (Model JEM 1200EX
supplied by Nippon Denshi) at an acceleration voltage of
80 kV at 2000 to 6000 magnifications. It was found that
the fiber had an islands-in-sea structure in which the
sea component was the cellulose. The maximum size of
the island component was 200 ~m and the minimum size of
the island component was 0.2 ~m (see Figs. 6 through 8).
In order to confirm that the island component was
composed of the protein, the slice of the fiber having a
separated soybean protein/cellulose weight ratio of 7/3
was dyed with Ali~arine Blue, a protein-staining dye,
and was observed by an optical microscope. It was found
that only the island component was dyed blue.
Comparative Example 1
The same separated soybean protein (Fuji-Pro R) as
used in Example 1 was dissolved at a concentration of
15% by weight in an aqueous solution of sodium hydroxide
having a concentration of 1.8% by weight, and a micro-
crystalline cellulose (Avicel ~ supplied by Asahi
~ 3t~21~7
- 25 -
Kasei Kogyo K.K.) was added to the solution and the
solution was stirred and mixed by a hi~h-speed stirrer
to prepare a dope in which the Acicel ~/soybean
protein weight ratio was 3/7. The formed dope was cast
on a glass sheet and coagulated in the same coagulating
bath as used in Example 1, followed by water washing, to
obtain a film.
When the film was dyed with Alizarine Blue and
observed by an optical microscope, it was found that
Avicel was dispersed as the island component in the
protein component (see Fig. 9).
Example 2
The water content of Alaska pulp was adjusted to
about 100% by weight and the pulp was subjected to a
blasting treatment under 30 kg/cm2 for 20 seconds to
obtain a cellulose having a polymerization degree
of 400. The cellulose was dissolved at a concentration
of 6.0% by weight in a 2.5 N aqueous solution of sodium
hydroxide.
Separately, corn starch was dissolved at a con-
centration of 5.0% by weight in a 2.5 N aqueous solution
of sodium hydroxide.
These solutions were mixed at a weight ratio of 5/6
to obtain a dope comprising the cellulose and corn
starch at a weight ratio of 1/1. The dope was deaerated
at 5000 rpm for 20 minutes by a centrifugal separator~
Then, the dope was cast on a glass sheet, coagulated in
a coagulating bath containing 14 g/dl of H2SO4 and
26 g/dl of Na2SO2 , and washed with water to form a
film.
In the same manner as described in Example 1, the
film was embedded in the resin and a slice was prepared.
The slice was observed by a transmission electron
microscope in the same manner as described in Example 1.
The entire phase was continuous and the corn starch
could not be distinguished from the cellulose portion
(see Fig. ~).
-` 1`3~Zi~7
- 26 -
When the slice was dyed with an iodine solution and
observed by an optical microscope, the slice was entirely
dyed a bluish violet color, and sea island components
could be discriminated.
Example 3
A regenerated cellulose nonwoven fabric (Benleese
supplied by Asahi Kasei Kogyo K.K.) was sufficiently
washed with water, dried and then dissolved at a con-
centration of 2.2% by weight in a 2.5 N a~ueous solution
of sodium hydroxide. Powdery corn starch (supplied by
Nippon Shokuhin Xogyo) was added to the thus-prepared
solution so that the cellulosetcorn starch weight ratio
was 2/8. The solution was stirred and mixed by a
high-speed stirrer (supplied by Nippon Seiki) to obtain
a homogeneous dope. The dope was filtered through a
250-mesh screen and extruded at a rate of 45 cc/min
through a nozzle having 150 holes, each having a diameter
of Q.25 mm, into a coagulating bath containing 14 g/dl
of H2SO4 and 26 g/dl of Na2SO4. The extrudate
was wound at a winding speed of 7 m/min to obtain an
edible protein fiber.
In the same manner as described in Example 1, the
obtained fiber was observed by a transmission electron
microscope. The entire fiber and a continuous network
structure.
A slice of the fiber was dyed with a 1 N iodine
solution and was observed by an optical microscope. It
was found that circular or ellipsoidal islands dyed a
bluish violet color and having a size of about 20 ~m
were dispersed in the sea component dyed a light bluish
violet color.
Example 4
The water content of Alaska pulp was adjusted to
lOQ% by weight, and the pulp was subjected to a blasting
treatment under 30 kg/cm2 for 20 seconds to obtain a
cellulose having a polymerization degree of 400.
A solution of this cellulose having a concentration
13~21~'7
- 27 -
of 4.5% by weight was prepared by using 2.5 N sodium
hydroxide as the solvent.
separately, a polypeptide shown in Table 1 was
dissolved at a concentration of 20% by weight in a 1.0 N
S solution of sodium hydroxide.
Both the solutions were mixed so that the cellulose/
polypeptide weight ratio was 1/1, and the mixed solution
was deaerated cast on a glass sheet, and immersed for 2
minutes in a coagulating bath containing 14 g/dl of
CaC12 and having a pH value adjusted to 2 to effect
coagulation. Then, the film was washed with water,
impregnated with an aqueous 1.5% solution of gylcerin
and naturally dried. In each case, a homogeneous
film was obtained, and the tensile strength of each
film was measure~. The obtained results are shown
in Table 1.
Table 1
Tensile strength
PolypePtide(kq/cm ) Remarks
20 Sodium casein 650 Undissolved p~rtion
was not observed
Separated soybean 480 Ditto
protein
Egg alb D 460 Ditto
ComParative Example 2
Alaska pulp having a polymerization degree of 1200
was dispersed at a concentration of 4.5% by weight in a
2.5 N solution of sodium hydroxide (the pulp was not
dissolved but an opaque dispersion was formed).
The polypeptide used in Example 4 was dissolved at
a concentration of 20% by weight in a 1.0 N aqueous
solution of sodium hydroxide.
Both the solutions were mixed so that the cellulose/
polypeptide weight ratio was 1/1, and an attempt was
40 made to form a film in the same manner as described in
-" 13~
- ~8 -
Example 4. In each case, coagulation occurred, but the
film was very brittle and measurement of the strength
was impossible.
Example 5
The water content of Alaska pulp was adjusted to
100% by weight and the pulp was subjected to a blasting
treatment under 30 kg/cm2 for 30 seconds to obtain a
cellulose having a polymerization degree of 350. The
cellulose was dissolved at a concentration of 5% by
weight in a 2.5 N aqueous solution of sodium hydroxide,
and water was added to the solution to form a solution
having a cellulose concentration of 3% by weight.
A separated soybean protein (Fuji-Pro R supplied by
Fuji Seiyu) was uniformly dissolved and dispersed in the
cellulose solution so that the cellulose/separated
soybean protein weight ratio was 2/8.
The formed dope was deaerated, extruded in a
coagulating bath containing 14 g/dl of sulfuric acid and
26 g/dl of sodium sulfate through a nozzle having 150
nozzles, each having a diameter of 0.25 mm, wound at a
winding speed of 10 m/min, and sufficiently washed with
water to obtain a fibrous molded body.
The obtained fiber had a preferred elasticity and
an excellent molded edible body. When eaten, the molded
body tasted very good.
Comparative Example 3
A cellulose obtained by grinding Alaska pulp having
a polymerization degree of 1200 was incorporated and
dispersed at a concentration of 3~ by weight in a 1.5 N
solution of sodium hydroxide.
In the same manner as described in Example 5, a
separated soybean protein was added to the cellulose
solution, and the mixed solution was spun.
The obtained molded body was very brittle, and when
eaten, the cellulose remained in the mouth and it did
not taste good.
Example 6
13~J 21~
-- 2g --
The water content of Alaska pulp was adjusted to
100% by weight, and the pulp was subjected to a blasting
treatment under 30 kg/cm for 20 seconds to obtain a
cellulose having a polymerization degree of 400. The
5 cellulose was dissolved at a concentration of 4.5% by
weight in a 2.5 N aqueous solution of sodium hydroxide.
Separately, a polysaccharide shown in Table 2 was
dissolved at a concentration of 10% by weight in a 1.5 N
aqueous solution of sodium hydroxide.
1 n Both solutions were mixed together so that the
cellulose/polysacCharide solution weight ratio was 1/1.
The mixed solution was da~lated , cast on a glass sheet,
immersed for 2 minutes in an aqueous solution containing
' 14 g/dl of CaC12 and having the pH value adjusted to 2,
immersed in water, impregnated with an aqueous 1.5%
solution of glycerin and naturally dried at room
temperature to obtain a homogeneous film.
The tensile strength of the film was measured. The
obtained results are shown in Table 2.
Note, the wet tensile strength was measured by
attaching a sample to a tensile tester, covering the
sample with paper impregnated with water, allowing the
sample to stand in this state for 5 minutes, and then
carrying out the tensile test.
Table 2
Tensile strength
(kq/cm2)
Polysaccharide REmarks
DrY state Wet state
3n Amylose from potato 770 85 Undissolved portion
not observed
Sodium alginate 680 72 ditto
Carrageenan 710 81 ditto
Comparative Example 4
Alaska pulp (having a polymerization degree of
. . . ~, .
1 3~21~7
- 30 -
1200) was dispersed at a concentration of 4.5% by weight
in a 2.5 N solution of sodium hydroxide ~the pulp was
not dissolved but was dispersed to form an opaque
dispersion).
In the same manner as described in Example 6, the
polysaccharide shown in Table 2 was mixed with the
cellulose so that the cellulose/polysaccharide weight
ratio was 1/1. Formation of a film was attempted in the
same manner as described in Example 6. However, although
the dope was coagulated, the obtained film was brittle
and measurement of the strength was impossible.
Example 7
A mixed dope was prepared by using amylose in the
same manner as described in Example 6 except that the
amylose/cellulose weight ratio was 7/3.
The dope was deaerated and extruded into a
coagulating bath containing 14 g/dl of sulfuric acid and
26 g/dl of sodium sulfate from a nozzle having 150
holes, each having a diameter of 0.25 mm. The extrudate
was wound at a winding speed of 10 m/min and sufficiently
washed with water to obtain a fibrous molded body.
When eaten the molded body, tasted very good.
Comparative Example 5
A cellulose obtained by grinding Alaska pulp
(having a polymerization degree of 1200) was dispersed
at a concentration of 4.5% by weight in 2.5 N sodium
hydroxide.
~ y using this cellulose dispersion and the amylose
solution used in Example 7, spinning was tried in the
same manner as described in Example 7. The obtained
molded product was very brittle.
Comparative Example 6
Sodium alginate and pullulan were dissolved in
water at a concentration of 10% by weight, and the
solution was cast and dried to obtain a film.
When measurement of the wet strength of the film
was tried in the same manner as described in Example 6,
~3~ 7
- 31 -
the measurement was impossible because the film broke on
contact with water,
Exam~le 8
The water content of Alaska pulp was adjusted to
00% by wei~ht and the pulp was subjected to a blasting
-eatment under 30 kg/cm for 20 seconds to obtain a
cellulose having a polymerization degree of 400. The
cellulose was dissolved at a concentration of 4.5~ by
weight in a 2.5 N aqueous solution of sodium hydroxide.
0 Separately, a living body constituent shown in
,able 3 was dissolved in a 1.5 N solution of sodium
hydroxide so that the solid content was 20% by weight.
Both the solutions were mixed together so that the
15 cellulose/living body constituent weight ~atie was 1/1.
The formed dope was deaerated, cast on a glass sheet, and
coagulated by immersion in a coagulating solution
containing 14 g/dl of CaCl2 and having the pH value
adjusted to 2 for 2 minutes. The formed film was washed
~n with water, impregnated with an aqueous 1.5~ solution of
glycerin and naturally dried at room temperature to
obtain a homogeneous film.
The tensile strength of the obtained film was
measured. The obtained results are shown in Table 3.
Table 3
Living body Tensile strength ~rks
~o constituent(kq/cm2)
RaW soybean 450 Some undissolved
portion observed
Defatted scy3ean 3~0 Ditto
Beef 480 Undissolved portion
not substantially
obser~
Gra~ fish meat520 Ditto
Comparative Example 7
:
- 32 -
Alaska pulp having a polymerization degree of 1200
was dispersed at a concentration of 4.5~ by weight in a
2.5 N solution of sodium hydroxide (the pulp was not
dissolved but an opaque dispersion was formed).
In the same manner as described in Example 8, the
living body constituent was mixed with the pulp dis-
persion so that the cellulose/living body constituent
weight ratio was 1.1. Formation of a film was attempted
in the same manner as described in Example 8. However,
coagulation did not occur and a film could not be
obtained.
Example 9
The water content of Alaska pulp was adjusted to
100% by weight and the pulp was subjected to a blasting
treatment under 30 kg/cm for 30 seconds to obtain a
cellulose having a polymerization degree of 350.
The cellulose was dissolved at a concentration of
3.0% by weight in a 2.5 N aqueous solution of sodium
hydroxide. Then, raw soybean powder (NI-Protein NIP-0
supplied by Gessetsu Kogyo) was incorporated into the
solution so that the cellulose/raw soybean powder weight
ratio was 3/7, and the soybean powder was emulsified and
dispersed at 5~C.
The obtained dope was deaerated and extruded into a
coagulating bath containing 14 g/dl of sulfuric acid and
26 g/dl of sodium sulfate from a nozzle having 50 holes,
each having a diameter of 0.25 mm. the extrudate was
wound at a winding speed of 11 m/min and sufficiently
washed with water to obtain a fibrous molded body.
The obtained fiber had an elasticity comparable to
that of natural meat and was an excellent edible molded
body.
Comparative Example 8
NI-Protein NIP-D was emulsified and dispersed at a
concentration of 10% by weight in 2.5 N sodium hydroxide.
In the same manner as described in Example 9, a
mixed dope was prepared and deaerated and spinning was
i3~21~.i7
attempted. ~owever, spinning was impossible because the
coagulating property was poor.
Example 10
Alaska pulp having a polymerization degree of 1200
was hydrolyzed at 60C for 120 minutes with 6 N sulfuric
acid to obtain a cellulose having a polymerization
degree of 410. The water content of the cellulose was
adjusted to 80~ by weight and the cellulose was treated
at a rotation number of 120 rpm and a temperature of
150C three times by using a twin-screw extruder
(supplied by Suehiro Tekkosho) having a screw diameter
of 80 mm and an L/D ratio of 8 to obtain a cellulose
having a polymerization degree of 370. A solution
containing 5% by weight of this cellulose was prepared
by using a 2.5 N solution of sodium hydroxide as the
solvent.
Separately, minced beef was dispersed in 2.5 N
sodium hydroxide.
Both the liquids were mixed together so that the
cellulose/beef (solid component) weight ratio was 2.8,
and the formed dope was deaerated and extruded into a
coagulating bath containing 14 g/dl of sulfuric acid and
26 g/dl of sodium sulfate from a nozzle having 150 holes,
each having a diameter of 0.25 mm. The extrudate was
25 wound at a winding speed of 10 m/min and sufficiently
washed with water to obtain a fibrous molded body. When
eaten the molded body tasted very good.
Comparative Example 9
A cellulose obtained by grinding Alaska pulp
(having a polymerization degree of 1200) was dispersed
at a concentration of 5% by weight in 2.5 N sodium
hydroxide. In the same manner as described in Example
10, a fibrous molded body was prepared by using the
thus-formed cellulose dispersion. The obtained molded
body was brittle, and when eaten, the cellulose remained
in the mouth and the molded body was not suitable as an
edible body.
13~)Zl'~7
- 34 -
Example 11
The same cellulose as used in Example 2 was
dissolved at a concentration of 2~ by weight in 2.5 N
sodium hydroxide, and Alaska pulp was dispersed in this
cellulose solution at a concentration of 4.5~ by weight
as the cellu]ose.
Potato starch was dissolved at a concentration of
10% by weight in a 2.5 N aqueous solution of sodium
hydroxide.
Both the liquids were mixed together so that the
total cellulose amount was equal to the amount of
starch. the formed dope was deaerated and cast on a
glass sheet. The glass sheet was immersed in an aqueous
solution containing 14 g/dl of sulfuric acid and 24 g/dl
of sodium sulfate for 2 minutes and then immersed in
water, followed by natural drying, to obtain a homo-
geneous film.
The tensile strength of the film was 240 kg/cm2.
When eaten, the film could be chewed but had a slight
cellulose taste.
