JP2022140110A - Food additive - Google Patents

Abstract

To provide a food additive that improves the flavor and texture of a retort food containing water and oil and fat, such as retort curry or retort stew.SOLUTION: A food additive contains cellulose nanofiber, preferably carboxymethylated cellulose nanofiber, and trehalose. The food additive gives an oil-releasing effect of properly separating oil in food without completely emulsifying it.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to food additives containing cellulose nanofibers and trehalose, and foods containing the same.

Retort foods such as retort curry and retort stew contain water and oils and fats, and are heated and cooked as they are. Therefore, good flavor and texture are obtained when water and fat are not sedimented and separated but are appropriately emulsified and dispersed.

Addition of cellulose has been proposed in order to improve the emulsifiability of water and fats and oils and improve the texture (Patent Documents 1 to 3).

JP-A-7-322865 JP-A-10-57022 Japanese Unexamined Patent Application Publication No. 2013-630

However, in the methods of Patent Documents 1 to 3, the texture of the retort food is not sufficiently improved, and the flavor is sometimes lowered.

Accordingly, an object of the present invention is to further improve the flavor and texture of retort food.

As a result of intensive studies in order to achieve this object, the present inventors have found that blending cellulose nanofibers (CNF) and trehalose is effective, and completed the present invention.

The present invention provides the following.
(1) A food additive containing cellulose nanofibers and trehalose.
(2) The food additive according to (1), wherein the cellulose nanofibers are anion-modified cellulose nanofibers.
(3) The food additive according to (1) or (2), wherein the anion-modified cellulose nanofiber is a cellulose nanofiber having a carboxyl group or a cellulose nanofiber having a carboxyalkyl group.
(4) The food additive according to (3), which is a carboxymethylated cellulose nanofiber having a degree of carboxymethyl substitution of the anion-modified cellulose nanofiber in the range of 0.01 to 0.50.
(5) The food additive according to any one of (1) to (4), which further contains carboxymethylated cellulose.
(6) A food containing the food additive according to any one of (1) to (5), water, and oil.
(7) The food according to (6), which is a retort food.

According to the present invention, the oil in the food is not completely emulsified, but is moderately separated, so that the taste can be improved.

The present invention will be described in detail below. In the present invention, "-" includes end values. That is, "X through Y" includes the values X and Y at both ends.

The food additive of the present invention contains cellulose nanofibers and trehalose. Trehalose is a non-reducing disaccharide in which two molecules of glucose are linked 1,1. Trehalose includes α,α-type trehalose (α-D-glucopyranosyl α-D-glucopyranoside), α,β-type (neotrehalose), and β,β-type (isotrehalose) isomers, preferably α, α-type trehalose can be used.

(cellulose nanofiber)
In the present invention, cellulose nanofibers (hereinafter sometimes referred to as CNF) are fine fibers made of pulp, which is a cellulose-based raw material, to the nanometer level, and have a fiber width of about 1 to 500 nm. . The average fiber diameter and average fiber length of cellulose nanofibers are obtained by averaging the fiber diameter and fiber length obtained from the results of observing each fiber using an atomic force microscope (AFM) or a transmission electron microscope (TEM). can be obtained by Well, the average aspect ratio of cellulose nanofibers is usually 50 or more. Although the upper limit is not particularly limited, it is usually 1000 or less. Average aspect ratio can be calculated by the following formula:
Aspect ratio = average fiber length/average fiber diameter

Cellulose nanofibers are obtained by refining pulp by applying mechanical force, and are composed of unmodified cellulose, carboxylated cellulose (also called oxidized cellulose), carboxymethylated cellulose, and phosphate groups. can be obtained by defibrating anion-modified cellulose such as cellulose introduced with , or modified cellulose such as cationized cellulose. The average fiber length and average fiber diameter of fine fibers can be adjusted by oxidation treatment and fibrillation treatment. In the present invention, it is preferable to use carboxymethylated (CM) cellulose nanofibers obtained by defibrating carboxymethylated cellulose obtained by performing carboxymethylation treatment.

(raw material for cellulose)
Cellulose raw materials for producing cellulose nanofibers used in the present invention include, for example, plant materials (for example, wood, bamboo, hemp, jute, kenaf, agricultural waste, cloth, pulp), animal materials (for example, sea squirt species), algae, microorganisms (eg, Acetobacter) products, and the like. As pulp, unbleached softwood kraft pulp (NUKP), bleached softwood kraft pulp (NBKP), unbleached hardwood kraft pulp (LUKP), bleached hardwood kraft pulp (LBKP), unbleached softwood sulfite pulp (NUSP), bleached softwood Sulfite pulp (NBSP), thermomechanical pulp (TMP), recycled pulp, used paper, and the like. Although all of these can be used, cellulose fibers derived from plants or microorganisms are preferred, and cellulose fibers derived from plants are more preferred.

(Carboxymethylation)
In the present invention, when carboxymethylated cellulose nanofibers are used, the carboxymethylated cellulose may be obtained by carboxymethylating the above cellulose raw material by a known method, or a commercially available product may be used. In any case, the degree of carboxymethyl substitution per anhydroglucose unit of the cellulose is preferably between 0.01 and 0.50. As an example of the method for producing such carboxymethylated cellulose, the following method can be mentioned. Cellulose is used as a starting material, and water or a lower alcohol in an amount of 3 to 20 times the mass is used as a solvent. Specifically, water, methanol, ethanol, N-propyl alcohol, isopropyl alcohol, N-butanol, isobutanol, tertiary butanol and the like can be used alone or in combination of two or more. When a mixed solvent of water and a lower alcohol is used, the mixing ratio of the lower alcohol is about 5 to 95% by mass. As the mercerizing agent, an alkali metal hydroxide, specifically sodium hydroxide or potassium hydroxide, is used in an amount of 0.5 to 20 times the moles of the anhydroglucose residue of the starting material. A bottom raw material, a solvent, and a mercerizing agent are mixed and mercerized at a reaction temperature of 0 to 70° C., preferably 10 to 60° C., for a reaction time of 15 minutes to 8 hours, preferably 30 minutes to 7 hours. . Thereafter, a carboxymethylating agent is added at 0.05 to 10.0 mol per glucose residue, the reaction temperature is 30 to 90° C., preferably 40 to 80° C., and the reaction time is 30 minutes to 10 hours, preferably 1 The etherification reaction is carried out for 1 hour to 4 hours.

<Carboxymethylated cellulose nanofiber>
The carboxymethylated cellulose nanofibers of the present invention maintain at least part of their fibrous shape even when dispersed in water. That is, when an aqueous dispersion of carboxymethylated cellulose nanofibers is observed with an electron microscope, a fibrous substance can be observed. Also, when carboxymethylated cellulose nanofibers are measured by X-ray diffraction, peaks of cellulose type I crystals can be observed.

<Crystallinity of cellulose type I>
The crystallinity of cellulose in the carboxymethylated cellulose nanofibers used in the present invention is 40% or more for crystalline type I, preferably 50% or more. When the crystallinity of cellulose type I is as high as 40% or more, the proportion of cellulose that maintains the crystal structure without dissolving in a solvent such as water is high, resulting in high thixotropy (thixotropy), thickeners, etc. become suitable for viscosity adjustment applications. In addition, for example, but not limited to, when added to a gel-like substance (for example, food, cosmetics, etc.), there is an advantage that excellent shape retention can be imparted. The crystallinity of cellulose can be controlled by the concentration of the mercerizing agent and temperature during treatment, as well as the degree of carboxymethylation. Since high concentrations of alkali are used in mercerization and carboxymethylation, type I crystals of cellulose tend to be converted to type II crystals. Desired crystallinity can be maintained by adjusting the degree. The upper limit of the crystallinity of cellulose type I is not particularly limited. Realistically, it is considered that the upper limit is about 90%.

The method for measuring the cellulose type I crystallinity of carboxymethylated cellulose nanofibers is as follows:
A sample is placed in a glass cell and measured using an X-ray diffraction measurement device (LabX XRD-6000, manufactured by Shimadzu Corporation). The crystallinity is calculated using the method of Segal et al., and the diffraction intensity at 2θ = 10 ° to 30 ° in the X-ray diffraction diagram is used as a baseline, and the diffraction intensity at 2θ = 22.6 ° 002 plane and 2θ = It is calculated by the following formula from the diffraction intensity of the amorphous portion at 18.5°.
Xc = (I002c - Ia)/I002c x 100
Xc = crystallinity of cellulose type I (%)
I002c: 2θ=22.6°, diffraction intensity of 002 plane Ia: 2θ=18.5°, diffraction intensity of amorphous portion.

The proportion of type I crystals in the carboxymethylated cellulose nanofibers is generally the same as in the carboxymethylated cellulose before nanofibers.

<Carboxymethyl substitution degree>
The carboxymethylated cellulose nanofibers used in the present invention have a degree of carboxymethyl substitution of 0.50 or less per anhydroglucose unit of cellulose. If the degree of carboxymethyl substitution exceeds 0.50, it is considered that the fiber dissolves in water and the fiber shape cannot be maintained. Considering the workability, the degree of substitution is preferably 0.01 to 0.50, more preferably 0.02 to 0.50, further preferably 0.05 to 0.40, More preferably 0.10 to 0.40. By introducing carboxymethyl groups into cellulose, the celluloses electrically repel each other, making it possible to defibrate into nanofibers. If it is too small, defibration will be insufficient, and cellulose nanofibers with high transparency may not be obtained. In the conventional aqueous method, it is difficult to obtain carboxymethylated cellulose nanofibers with a cellulose type I crystallinity of 50% or more when the degree of carboxymethyl substitution is in the range of 0.20 to 0.40. However, the present inventors have found, for example, by the method described later, carboxymethylation having a degree of carboxymethyl substitution in the range of 0.20 to 0.40 and a crystallinity of cellulose type I of 50% or more We have found that cellulose nanofibers can be produced. The degree of carboxymethyl substitution can be adjusted by controlling the added amount of the carboxymethylating agent to be reacted, the amount of the mercerizing agent, the composition ratio of water and the organic solvent, and the like.

Anhydroglucose units in the present invention mean individual anhydroglucose (glucose residues) constituting cellulose. In addition, the degree of carboxymethyl substitution (also referred to as the degree of etherification) refers to the ratio of hydroxyl groups in glucose residues that constitute cellulose that are substituted with carboxymethyl ether groups (carboxymethyl ether per glucose residue). number of ether groups). The degree of carboxymethyl substitution may be abbreviated as DS.

The method for measuring the degree of carboxymethyl substitution is as follows:
About 2.0 g of the sample is precisely weighed and placed in a 300 mL Erlenmeyer flask with a common stopper. Add 100 mL of a liquid obtained by adding 100 mL of special grade concentrated nitric acid to 1000 mL of methanol nitrate and shake for 3 hours to convert the salt of carboxymethylated cellulose nanofibers (CMC) to H-CMC (hydrogenated carboxymethylated cellulose nanofibers). . Accurately weigh 1.5 to 2.0 g of the absolute dry H-CMC and put it in a 300 mL Erlenmeyer flask with a common stopper. Wet the H-CMC with 15 mL of 80% methanol, add 100 mL of 0.1 N NaOH, and shake at room temperature for 3 hours. Excess NaOH is back-titrated with 0.1N—H ₂ SO ₄ using phenolphthalein as an indicator, and the degree of carboxymethyl substitution (DS value) is calculated by the following equation.
A = [(100 x F'-0.1N _- H2SO4 ₍ mL) x F) x 0.1]/(H-CMC
Absolute dry mass (g))
Carboxymethyl substitution degree = 0.162 × A / (1-0.058 × A)
F′: factor of 0.1N—H ₂ SO ₄ F: factor of 0.1N—NaOH.

The degree of carboxymethyl substitution in the nanofibers of carboxymethylated cellulose is generally the same as the degree of carboxymethyl substitution in the carboxymethylated cellulose before nanofibers.

<Fiber diameter, aspect ratio>
The carboxymethylated cellulose nanofibers used in the present invention have a nanoscale fiber diameter. The average fiber diameter is preferably 3 nm to 500 nm, more preferably 3 nm to 150 nm, still more preferably 3 nm to 20 nm, still more preferably 5 nm to 19 nm, still more preferably 5 nm to 15 nm.

The aspect ratio of the carboxymethylated cellulose nanofibers is not particularly limited, but is preferably 350 or less, more preferably 300 or less, further preferably 200 or less, further preferably 120 or less. , is more preferably 100 or less, and more preferably 80 or less. When the aspect ratio is 350 or less, the fibers are not excessively long, the entanglement between the fibers is reduced, and the generation of clumps (lumps) of cellulose nanofibers can be reduced. Suitable. In addition, since it has high fluidity, it is easy to use even at a high concentration, and there is an advantage that it is easy to use even in applications where a high solid content is required. Although the lower limit of the aspect ratio is not particularly limited, it is preferably 25 or more, more preferably 30 or more. When the aspect ratio is 25 or more, the effect of improving thixotropy can be obtained from the fibrous shape. The aspect ratio of carboxymethylated cellulose nanofibers can be controlled by the mixing ratio of solvent and water during carboxymethylation, the amount of chemicals added, and the degree of carboxymethylation, and can be produced, for example, by the method described below. .

The average fiber diameter and average fiber length of nanofibers of carboxymethylated cellulose are measured using an atomic force microscope (AFM) when the diameter is 20 nm or less, and a field emission scanning electron microscope (FE-SEM) when the diameter is 20 nm or more. It can be measured by analyzing 200 randomly selected fibers and calculating the average. Also, the aspect ratio can be calculated by the following formula:
Aspect ratio = average fiber length/average fiber diameter.

(defibration)
The fibrillation of the cellulose raw material may be performed before or after the modification treatment of the cellulose raw material. In addition, defibration may be performed at once or may be performed multiple times. In the case of multiple times, each defibration time may be any time.

The apparatus used for fibrillation is not particularly limited, but examples thereof include apparatuses of types such as high-speed rotary type, colloid mill type, high pressure type, roll mill type, and ultrasonic type. Or an ultrahigh pressure homogenizer is more preferable. The apparatus is preferably capable of applying strong shear forces to the cellulose raw material or modified cellulose (usually the dispersion). The pressure that can be applied by the device is preferably 50 MPa or higher, more preferably 100 MPa or higher, and still more preferably 140 MPa or higher. The device is preferably a wet high-pressure or ultra-high pressure homogenizer capable of applying the above pressure to the cellulose raw material or modified cellulose (usually dispersion liquid) and applying a strong shearing force. Thereby, defibration can be performed efficiently.

When defibrating a dispersion of cellulose raw materials, the solid content concentration of the cellulose raw material in the dispersion is usually 0.1% by mass or more, preferably 0.2% by mass or more, and more preferably 0.3. % by mass or more. As a result, the amount of liquid becomes appropriate with respect to the amount of cellulose fiber raw material, which is efficient. The upper limit is usually 10% by mass or less, preferably 6% by mass or less. Thereby, fluidity can be maintained.

Prior to defibration (preferably fibrillation with a high-pressure homogenizer) or, if necessary, a dispersing treatment prior to fibrillation, a preliminary treatment may be performed as necessary. Pretreatment may be performed using a mixing, stirring, emulsifying, or dispersing device such as a high-speed shear mixer.

(dry)
The cellulose nanofibers used in the present invention can be used in the form of a dispersion obtained after fibrillation, but can also be dried and redispersed in water if necessary. Although the drying method is not limited at all, for example, freeze drying, spray drying, tray drying, drum drying, belt drying, drying by spreading thinly on a glass plate, etc., fluidized bed drying, microwave drying. Known methods such as drying method, heat-generating fan type vacuum drying method, etc. can be used. After drying, if necessary, it may be pulverized with a cutter mill, hammer mill, pin mill, jet mill, or the like. Moreover, the method of redispersion in water is not particularly limited, either, and a known dispersing device can be used.

The form of the cellulose nanofibers used in the present invention may be in the form of a dispersion or in the form of powder. From the viewpoint of excellent workability in the production of fried foods, the cellulose nanofibers are used in the form of a dispersion. is preferred.

The cellulose nanofibers of the present invention may contain other components as necessary. For example, when producing a powder, it is preferable to allow a water-soluble polymer to coexist with a dispersion of cellulose nanofibers before drying, because redispersibility is improved.

<Water-soluble polymer>
Examples of water-soluble polymers include cellulose derivatives (carboxymethylcellulose, methylcellulose, hydroxypropylcellulose, ethylcellulose), xanthan gum, xyloglucan, dextrin, dextran, carrageenan, locust bean gum, alginic acid, alginate, pullulan, starch, potato starch, Arrowroot powder, cornstarch, gum arabic, locust bean gum, gellan gum, polydextrose, pectin, chitin, water-soluble chitin, chitosan, casein, albumin, soybean protein solution, peptone, tamarind gum, guar gum, and the like. Among these, cellulose derivatives are preferable from the viewpoint of affinity with carboxymethylated cellulose nanofibers, and carboxymethylcellulose and salts thereof are particularly preferable. A water-soluble polymer such as carboxymethylcellulose and its salt is considered to enter between carboxymethylated cellulose nanofibers and increase the distance between the nanofibers, thereby improving the redispersibility. Further, water-soluble dextrin is preferable because it has a high suppressive effect on mamako.

When carboxymethylcellulose or a salt thereof is used as the water-soluble polymer, it is preferable to use carboxymethylcellulose having a degree of carboxymethyl group substitution per anhydroglucose unit of 0.55 to 1.6, more preferably 0.55 to 1.6. 1 is more preferred, and 0.65 to 1.1 is even more preferred. In addition, longer molecules (higher viscosity) are preferable because they are more effective in widening the distance between nanofibers. In addition, the B-type viscosity at 25 ° C. and 60 rpm in a 1% by mass aqueous solution of carboxymethyl cellulose is preferably 3 mPa s to 14000 mPa s, more preferably 7 mPa s to 14000 mPa s, and 1000 mPa s to 8000 mPa s. More preferred. The term "carboxymethyl cellulose or a salt thereof" as a water-soluble polymer used herein is completely soluble in water. Distinguished from fibers.

The content of the water-soluble polymer is preferably 5% by mass to 300% by mass, more preferably 20% by mass to 300% by mass, and 25% by mass to 200% by mass is more preferable, and 25% to 60% by mass is more preferable.

Foods to which the food additive of the present invention is applied are not particularly limited, but liquid foods containing water and fats and oils are preferable, and application to retort foods is particularly preferable.

The oil is not particularly limited as long as it can be used for food, and one or more of vegetable oils, animal oils, fractionated oils, hydrogenated oils, and transesterified oils may be used, or two or more may be used in combination. can. Examples of vegetable fats and oils include corn, cottonseed, coconut, palm, soybean, sesame, rice, safflower, peanut, rapeseed, sunflower, cocoa butter, olive and palm kernel oils, vegetable sterols. , vegetable stanols, sterol esters, medium-chain fatty acids, and animal fats and oils include milk fat, lard, beef tallow, fish oil, tallow, and the like.

Examples of retort food include retort curry, retort stew, retort sauce, retort soup, and various retort side dishes. It can also be used for concentrated retort foods that are cooked with water.

The food of the present invention can contain the cellulose nanofibers of the present invention in any amount, but it is preferable to contain the cellulose nanofibers in an effective amount. The amount of cellulose nanofibers added to food is preferably 0.001 to 2% by mass. Moreover, the amount of trehalose added to the food is preferably 0.05 to 5% by mass. If the amount of cellulose nanofibers added is less than the lower limit of the above addition amount, fats and oils are excessively separated, so there is a possibility that sufficient effect for improving flavor cannot be obtained. On the other hand, when the upper limit of the amount to be added is exceeded, the fat and oil are excessively emulsified, which may deteriorate the flavor.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these.

(Method for measuring degree of carboxymethyl substitution)
1) About 2.0 g of carboxymethylated cellulose fiber (absolute dry) is precisely weighed and placed in a 300 mL Erlenmeyer flask with a common stopper.
2) Add 100 mL of a solution obtained by adding 100 mL of special grade concentrated nitric acid to 1000 mL of nitric acid methanol, and shake for 3 hours to convert carboxymethyl cellulose salt (CM cellulose) into hydrogen-type CM cellulose.
3) Accurately weigh 1.5 to 2.0 g of hydrogenated CM cellulose (absolutely dry) and put it in a 300 mL conical flask equipped with a common stopper.
4) Wet the hydrogenated CM-cellulose with 15 mL of 80% methanol, add 100 mL of 0.1N NaOH, and shake at room temperature for 3 hours.
₅ ) _Backtitrate excess NaOH with 0.1N H2SO4 using phenolphthalein as indicator.
6) Calculate the degree of carboxymethyl substitution (DS) by the formula:
A=[(100×F′−(0.1N H ₂ SO ₄ ) (mL)×F)×0.1]/(absolute dry mass of hydrogen-type CM cellulose (g))
DS = 0.162 x A/(1 - 0.058 x A)
A: Amount of 1N NaOH (mL) required to neutralize 1 g of hydrogenated CM-cellulose
F′: Factor of 0.1N H ₂ SO ₄ F: Factor of 0.1N NaOH (Method for measuring average fiber diameter and aspect ratio)
The average fiber diameter and average fiber length of CNF were analyzed for 200 randomly selected fibers using an atomic force microscope (AFM). The aspect ratio was calculated by the following formula.
Aspect ratio = average fiber length/average fiber diameter

[Example 1]
(Preparation of carboxymethylated cellulose nanofibers)
1089 parts of isopropanol (IPA) and 31 parts of sodium hydroxide dissolved in 121 parts of water were added to a 5 L twin-screw kneader whose rotation speed was adjusted to 100 rpm, and hardwood pulp (manufactured by Nippon Paper Industries Co., Ltd., LBKP) was charged at 200 parts by dry mass when dried at 100° C. for 60 minutes. The mixture was stirred and mixed at 30°C for 60 minutes to prepare mercerized cellulose. Further, 117 parts of sodium monochloroacetate was added with stirring, and after stirring at 30°C for 30 minutes, the temperature was raised to 70°C over 30 minutes, and carboxymethylation reaction was carried out at 70°C for 60 minutes. The proportion of water in the reaction medium during the mercerization reaction and the carboxymethylation reaction was 10% by mass. After completion of the reaction, the sodium salt of carboxymethylated cellulose having a carboxymethyl substitution degree of 0.27 and a cellulose type I crystallinity of 64% was neutralized, washed with 65% aqueous methanol, deliquored, dried, and pulverized. got The methods for measuring the degree of carboxymethyl substitution and the crystallinity of cellulose type I are as described above.
The resulting sodium salt of carboxymethylated cellulose was dispersed in water to form a 1% (w/v) aqueous dispersion. This was treated with a high-pressure homogenizer at 150 MPa three times to obtain a dispersion of carboxymethylated cellulose nanofibers. The obtained carboxymethylated cellulose nanofibers had an average fiber diameter of 3.2 nm and an aspect ratio of 40.
The obtained carboxymethylated cellulose nanofibers were made into a dispersion with a solid content of 0.7% by mass with water, and carboxymethylcellulose (manufactured by Nippon Paper Industries Co., Ltd., trade name: F350HC-4, viscosity (1% by mass, 25°C, 60 rpm) about 3000 mPa s, carboxymethyl substitution degree about 0.90) is 40% by mass with respect to carboxymethylated cellulose nanofibers (that is, when the solid content of carboxymethylated cellulose nanofibers is 100 parts by mass The solid content of carboxymethyl cellulose was 40 parts by mass), and the mixture was stirred with a TK homomixer (12,000 rpm) for 60 minutes.
After adjusting the pH to 9 by adding 0.5% by mass of an aqueous sodium hydroxide solution to the dispersion, the dispersion was applied to the surface of a drum of a drum dryer D0405 (manufactured by Katsuragi Industry Co., Ltd.) and dried at 140° C. for 1 minute. The resulting dried material was scraped off and then pulverized using an impact mill at a rate of 10 kg per hour to obtain a dry pulverized material having a water content of 5% by mass. The resulting pulverized material was classified using a 30 mesh to obtain a powder (CNF powder 1) containing carboxymethylated cellulose nanofibers and carboxymethyl cellulose.

(Production of retort pouch curry)
After adding 0.02% of the above CNF powder 1 and 1% of trehalose to a commercially available retort curry, stirring at 5000 rpm using a TK homomixer, and then heating to about 80 ° C. , adjusted the retort curry. This was sampled by 10 panelists, and the flavor was evaluated on a scale of 1 to 10, and the average value was evaluated.

[Comparative Example 1]
A retort curry was prepared in the same manner as in Example 1, except that no food additive was added. This was sampled by 10 panelists, and the flavor was evaluated on a scale of 1 to 10. When the average value was evaluated, the score was 4 to 7.

Claims (7)

A food additive containing cellulose nanofibers and trehalose. The food additive according to claim 1, wherein the cellulose nanofibers are anion-modified cellulose nanofibers. 3. The food additive according to claim 1, wherein the anion-modified cellulose nanofiber is a cellulose nanofiber having a carboxyl group or a cellulose nanofiber having a carboxyalkyl group. The food additive according to claim 3, wherein the anion-modified cellulose nanofiber is a carboxymethylated cellulose nanofiber having a degree of carboxymethyl substitution in the range of 0.01 to 0.50. The food additive according to any one of claims 1 to 4, further comprising carboxymethylated cellulose. A food comprising the food additive according to any one of claims 1 to 5, water, and oil. The food according to claim 6, wherein the food is retort food.