JP2019172995A - Nanofiber derived from citrus peel, and method for producing the same - Google Patents

Abstract

Kind Code: A1 Abstract: A method for producing citrus peel nanofibers, wherein the fiber width can be efficiently defibrated to the nanometer level without chemically treating a citrus-derived peel with an enzyme or a drug, and the like, can be obtained by the method. Provided are citrus peel nanofibers, and food or cosmetic compositions containing the nanofibers. A method for producing citrus peel nanofibers having the following steps (1) and (2): (1) a step of pulverizing citrus peel into a paste, and (2) a step obtained by step (1). Citrus peel paste, the step of defibration treatment, 2 to 10 nm wide citrus peel nanofibers, the thixotropic index of 2 to 10 when the aqueous dispersion of solid content concentration 0.5 to 10 mass%. A nanofiber and a food or cosmetic composition containing the nanofiber. [Selection diagram] None

Description

  The present invention relates to a nanofiber for citrus peel, a food or cosmetic composition containing the nanofiber, and a method for producing a nanofiber for citrus peel.

  Recently, many researches have been conducted on the production and use of cellulose nanofibers as high-performance nanofibers obtained from plant resources based on research reports that cellulose nanofibers are lightweight and have strengths five times that of steel. It has been broken. Most of these studies use wood fibers derived from wood pulp such as conifers and hardwoods.

  As a method for producing cellulose nanofibers from these wood fibers, there are a grinder method using a stone mill type friction machine such as a grinder, an underwater collision method, a high-pressure homogenizer method, etc., but it is necessary to repeat the treatment many times. . In addition, there is a method by which cellulose nanofibers with a uniform width of about 4 nm can be easily obtained by a chemical treatment method called TEMPO oxidation that selectively introduces carboxyl groups on the cellulose surface. It is necessary to introduce a carboxyl group on the surface, and cellulose nanofibers that are not chemically modified cannot be obtained.

  In Patent Document 1, plant-derived cellulose nanofibers having a width of 10 to 50 nm can be efficiently obtained by stirring a plant-derived fiber aggregate containing no lignin or a specific amount of lignin in a liquid substance. It has been reported. However, chemical treatment is required in the process of removing lignin.

  Patent Document 2 reports that by adding cellulose nanofibers to foods, strength and hardness can be improved, and texture such as stiffness can be improved. The cellulose nanofibers used in the invention are patented. It can be produced by the method described in Document 3.

  Patent Document 3 reports a method for producing a very small fiber that does not include micron-order fibers, has an average fiber diameter of nanometer size, and a uniform fiber diameter. The production method uses a special homogenizer. It is disclosed that the homogenization treatment is repeated 5 to 100 times.

  Citrus peel is known to contain various functional components such as many dietary fibers and polymethoxyflavone. However, most of the squeezed residue such as citrus peels produced in citrus juice factories is used as livestock feed and fertilizer after squeezing, but most of them are disposed of as industrial waste. Use is desired. Unlike timber, citrus peel has the functionality of food, and if it can be made into nanofibers without chemical treatment, it may be used for other purposes than wood. Furthermore, if nanofibers can be easily produced from citrus peel, the cost can be reduced.

JP 2010-216021 A JP 2013-236585 A JP 2011-26760 A

  INDUSTRIAL APPLICABILITY The present invention provides a method for producing citrus peel nanofibers that can efficiently defibrate the fiber width to the nano level without chemically treating the citrus peel with an enzyme or a drug, etc. An object of the present invention is to provide a citrus peel nanofiber, and a food or cosmetic composition containing the nanofiber.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have performed a fibrillation treatment after citrus peel is subjected to a fibrillation treatment, so that the functionality possessed by the peel is maintained relatively easily. The knowledge that it could be defibrated to fiber was obtained. Furthermore, the dispersibility of the juice can be improved by adding citrus peel nanofibers obtained by such a method to the juice, and the viscosity can be recovered even when frozen or dried, Has been found to be excellent in water absorption when it is in a dry powder form.

  The present invention has been completed based on these findings, and has been completed. The following nanofibers of citrus peel, food or cosmetic composition containing the nanofibers, and method of producing citrus peel nanofibers Is to provide.

Item 1. A nanofiber of citrus peel with a width of 2 to 10 nm,
A nanofiber having a thixotropic index of 2 to 10 when an aqueous dispersion having a solid content concentration of 0.5 to 10% by mass is obtained.
Item 2. Item 2. The nanofiber according to Item 1, further comprising at least one selected from the group consisting of aurapten, naringin, nariltin, hesperidin, sinensetin, nobiletin, heptamethoxyflavone, and tangeretin.
Item 3. The citrus fruits are Kawachi Bankan, Unshu Mandarin, Ponkan, Kiyomi, Shiranui, Iyokan, Orange, Lemon, Lime, Eggplant, Sweet Summer, Hachiman, Bundan, Grapefruit, Kanpei, Ehime Fruit Trial 28, Natsumikan, Setuka , Kara, Harumi, Harehime, Haruka, Nantsukai, Navel Orange, Amakusa, Marihime, Hyuga Summer, Tarocco, Daidai, Himetsuki, Encore, Seminole, Kavos, Moro, Jara, Tamami, Golden Citrus, Ansei Kan , Tenka, Sudachi, Kumquat, Sweet Spring, Rei, Marcot, Tsunoka, Tomoko, Sakwasa, HimeAkari, Nishinoka, Sanhokan, Southern Yellow, Aiome, Chandra Pomelo, Orange Hinata, Kishu Mandarin, Hayaka , At least one selected from the group consisting of Bambooille, Yuko, Fukuhara Orange, Aurastar and Buddha Or nanofibers according to 2.
Item 4. Item 4. The nanofiber according to any one of Items 1 to 3, which is in a dry powder state or a frozen state.
Item 5. Item 5. The nanofiber according to any one of Items 1 to 4, which is in a dry powder form and has a water absorption rate of 1000% or more.
Item 6. The foodstuff or cosmetics composition containing the nanofiber as described in any one of claim | item 1 -5.
Item 7. Item 7. The composition according to Item 6, which is a thickener, gelling agent, shape-retaining agent, emulsifier or dispersion stabilizer.
Item 8. The manufacturing method of the nanofiber of the citrus fruit peel which has the process of following (1) and (2):
(1) A step of pulverizing citrus peel into a paste,
(2) A step of defibrating the citrus peel paste obtained in step (1).
Item 9. Item 9. The production method according to Item 8, wherein in the step (1), the pulverization is performed with a high-speed shear stirrer.
Item 10. In item 8 or 9, in the step (2), the defibrating treatment is performed by a stone mill grinder, a high-pressure homogenizer, a refiner, a biaxial extruder, a water jet method, an underwater counter collision method, a bead mill, a ball mill, or a microfluidizer. The manufacturing method as described.
Item 11. Claim | item 8-10 manufacturing method as described in any one of claim | item 8-10 which uses the citrus peel previously immersed in the said process (1).

  According to the method for producing nanofibers of citrus peel according to the present invention, the fiber width can be efficiently increased while maintaining the functionality of the peel without undergoing chemical treatment with enzymes or drugs or complicated manufacturing processes. It can be defibrated to the nano level.

  Furthermore, the nanofiber of the citrus peel of this invention can improve the dispersibility of fruit juice by adding to fruit juice, and also has high water absorption, when it is a dry powder form.

2 is a photograph showing an SEM image after 6 disc mill processes in Example 1. FIG. 3 is a graph showing functional component concentrations for each number of disk mill processes in Example 1. It is a graph which shows the viscosity for every disk mill processing frequency in Example 2 (5% of solid content). It is a graph which shows the viscosity for every disk mill processing frequency in Example 3 (solid content 3%). It is a graph which shows the viscosity for every disk mill processing frequency in Example 4 (solid content 3%). It is a graph which shows the viscosity for every drying condition in Example 5 (5% of solid content). It is a graph which shows the viscosity for every freezing conditions in Example 6 (solid content 3%). It is a graph which shows the viscosity for every number of high-pressure homogenizer processes in Example 7 (75 MPa) (solid content 3%). It is a graph which shows the viscosity for every high frequency homogenizer process frequency in Example 7 (150 MPa) (solid content 3%). It is a figure which shows the analysis result of the fiber width from the AFM photograph of Kawauchi late citrus peel origin nanofiber (75MPa, 1 time processing) in Example 7. It is a figure which shows the result of the solution stability test of the nanofiber in Kawachi late citrus juice in Example 8. Upper left: Binfisu standard manufactured by Sugino Machine, upper right: Nanofibers derived from Kawachi late citrus pericarp mesocarp, lower: Nanofibers derived from Kawachi late citrus capsule

  Hereinafter, the present invention will be described in detail.

  In the present specification, “comprise” includes the meaning of “essentially consist of” and the meaning of “consist of”.

  The nanofiber of the citrus peel of the present invention has a width of 2 to 10 nm and a thixotropic index of 2 to 10 when an aqueous dispersion having a solid content concentration of 0.5 to 10% by mass is characterized.

  The citrus fruits in the present invention are preferably Kawachi Bankan, Unshu orange, Ponkan, Kiyomi, Shiranui (Decomon (registered trademark)), Iyokan, orange, lemon, lime, coconut, sweet summer, Hachiman, Buddha, grapefruit, sweet Taira, Atago Fruit Trial 28 (Red Mado (registered trademark)), Natsumikan, Setoka, Kara, Harumi, Harehime, Haruka, Minamitsukai, Navel Orange, Amakusa, Marihime, Hinata, Tarocco, Daidai, Himetsuki, Encore, Seminole, Kavos, Moro, Jabara, Tamami, Golden Tangerine, Anzai Tangerine, Tenka, Sudachi, Kumquat, Sweet Spring, Rei, Marcot, Tsunoka, Toshiharu, Shikuwasa, Hime Akari, Nishino Incense, Sanpokan, Southern Yellow, Aiome, Chandra Pomero, Orange Hyuga, Kishu Mikan, Hayaka, Bumpei, Yuko, Fukuhara Orange, Aura Star and Buddha citrus, more preferably Kawachi mandarin, Wenzhou mandarin, Ponkan and Iyokan, and particularly preferably Kawachi mandarin. Citrus can be used alone or in combination of two or more.

  Kawachi Bankan is a kind of pomelo (Citrus maxima, Citrus grandis), and is a natural hybrid that draws the blood of the Buddha.

  The citrus peel according to the present invention includes an outer peel (flavedo), a mesocarp (albedo), a funnel membrane and a sandbag, and preferably an outer peel, a mesocarp and a fungus. When utilizing the functionality derived from citrus peel, outer skin and mesocarp are preferable, and when it is desired to improve dispersibility and viscosity, a funnel membrane having a high cellulose content is preferable. In addition, although it can be used properly for each application, various characteristics can be obtained by mixing. In addition, when utilizing the color derived from citrus peel, outer skin is preferable.

  As citrus peel, what is obtained after squeezing citrus fruits can be used, for example. As the citrus peel, any squeezing method can be used without limitation, and examples of the squeezing method include in-line squeezing, belt squeezing, and chopper pulper squeezing. In the in-line juice, citrus fruits enter the lower cup one by one with the whole fruit, make a hole in the bottom of the fruit and hold it with the upper cup from the top, and the fruit meat enters the strainer tube and is squeezed by the orifice and squeezed. Since the chopper pulper juice is characterized by squeezing after peeling the peel, the peel peeled before squeezing can be used.

  As a citrus peel, a raw state, a frozen state, a dried state, a state in which these are cut, and the like can be used. The method for drying the citrus peel is not particularly limited, and examples thereof include sun drying, ventilation drying, forced drying, and freeze drying. As a method of cutting the citrus peel, various known cutting or crushing methods used in the food field can be used.

  The citrus peel nanofiber can be obtained by defibrating the citrus peel. As the citrus peel nanofiber of the present invention, citrus peel cellulose nanofiber is preferable. The method for producing the citrus peel nanofiber of the present invention is not particularly limited, and a known method can be used, and a method described later is preferable.

  The fiber width of the nanofiber of the citrus peel of the present invention is usually 2 to 50 nm, preferably 2 to 10 nm, more preferably 2 to 5 nm.

  The thixotropic index (hereinafter sometimes referred to as “TI value”) is a ratio of the viscosity obtained by dividing the viscosity value measured at a rotational speed of 6 rpm by the viscosity value measured at 60 rpm. The viscosity value is an aqueous solution prepared by adjusting the citrus peel nanofiber of the present invention to a solid content concentration of 0.5 to 10% by mass, preferably at 20 ° C., using a viscometer at a rotation speed of 6 rpm or 60 rpm (particularly after 1 minute). It is measured. The viscosity can be measured according to, for example, JISK5101-6-2. The solid content of the solid content concentration in the present specification does not include monosaccharide and disaccharide sugars. Examples of the viscometer include a B-type rotary viscometer (DV-III Ultra manufactured by Brookfield). The TI value is preferably 4-10.

  The nanofiber of the citrus peel of the present invention has a viscosity at 10 rpm when it is an aqueous dispersion having a solid content concentration of 5% by mass, usually 5000 mPa · S or more, preferably 10000 mPa · S or more, more preferably 15000 mPa · S or more. It is. Viscosity measurement conditions are the same as above.

  The citrus peel nanofiber of the present invention preferably contains one or more functional components such as aurapten, naringin, nariltin, hesperidin, sinensetin, nobiletin, heptamethoxyflavone, tangeretin, and β-cryptoxanthin.

  The form of the nanofiber of the citrus peel of the present invention is not particularly limited, and examples thereof include paste, jelly, solution, suspension, emulsion, powder, granule, and solid. The nanofibers of the citrus peel of the present invention can also be made into a dry powder form. In this case, the viscosity can be recovered by adding a liquid again. Further, it can be stored even in a frozen state, and its viscosity can be recovered to some extent even after thawing.

  When the nanofiber of the citrus peel of this invention is a dry powder form, it has high water absorption. The water absorption rate of the citrus peel nanofiber of the present invention is preferably 1000% or more, more preferably 1500% or more, and still more preferably 2000% or more. The water absorption rate here is a value measured by the method described in the examples.

  The citrus peel nanofibers of the present invention are not limited to those composed only of nanofibers, but include the functional components described above, fibers remaining after being defibrated and not formed into nanofibers, and aggregates of nanofibers. It also includes the inclusions.

  The food or cosmetic composition of the present invention is characterized by comprising the above-mentioned citrus peel nanofibers.

  The food composition of the present invention includes all foods and drinks that can be consumed by animals (including humans). The type of the food or drink is not particularly limited. For example, beverages (tea, drink yogurt, juice, juice-containing beverages, soft drinks, milk, soy milk, coffee, sports beverages, carbonated beverages, alcoholic beverages, etc.); Pudding, crackers, biscuits, cookies, cakes, jelly, candy, chocolate, chewing gum, ice cream, baked goods, Japanese confectionery, etc .; Foods (bread, dry bread, udon, soba, ramen, pasta, ham, tofu, konjac, boiled Seasonings (miso, soy sauce, dressing, mayonnaise, sauce, sprinkle, soup stock); dairy products (yogurt, cheese, butter, etc.); marine products (chikuwa, Rice cake, jakoten, etc.); rice-derived products (rice cake, rice cake, etc.).

  The food composition of the present invention includes foods and drinks intended for health, health maintenance, promotion, etc., for example, health foods, functional foods, dietary supplements, supplements, foods for specified health use, functional nutrition foods, functional indications Foods and the like are also included.

  In addition to the above-mentioned citrus peel nanofibers, the food composition of the present invention includes vitamins, minerals, flavonoids, quinones, polyphenols, sweeteners, amino acids, nucleic acids, essential fatty acids, refreshing as necessary. Agents, emulsifiers, binders, disintegrants, lubricants, colorants, fragrances, stabilizers, preservatives, brighteners, sustained release regulators, surfactants, excipients, solubilizers, wetting agents, etc. Additives can be blended.

  The cosmetic composition of the present invention includes all cosmetics applied to the skin, mucous membranes, body hair, scalp hair, scalp, nails, teeth, face skin, lips, etc. of animals (including humans).

  The dosage form of the cosmetic composition of the present invention includes an aqueous solution system, a solubilization system, an emulsion system, a powder system, an oil liquid system, a gel system, an ointment system, an aerosol system, a water-oil two-layer system, and a water-oil-powder. A wide range of dosage forms such as a three-layer system can be adopted.

  The use of the cosmetic composition of the present invention is also arbitrary. For example, in the case of basic cosmetics, skin lotions, emulsions, creams, essences, gels, serums, packs, masks, etc. may be mentioned. , Foundation, lipstick, blusher, eyeliner, eye shadow, mascara, etc., nail cosmetics include nail polish, base coat, top coat, light removal liquid, etc. ) Dentifrice, mouthwash, massage agent, cleansing agent, shaving cream, after shave lotion, pre-shave lotion, body soap, soap, shampoo, rinse, hair treatment, hair conditioner, hair nicking agent, hair restorer, antiperspirant, Examples include bath salts and sunscreen creams.

  In the cosmetic composition of the present invention, in addition to the above-mentioned citrus peel nanofibers, components usually used in cosmetics, for example, whitening agents, moisturizers, oily components, antioxidants, ultraviolet absorbers, surfactants, enhancers A viscous agent, alcohols, powder components, coloring materials, aqueous components, water, various skin nutrients, and the like can be appropriately blended as necessary.

  The ratio of the nanofibers of the citrus peel contained in the food or cosmetic composition of the present invention is usually 0.01 to 99% by mass, preferably 1 to 80% by mass, more preferably 10 to 70% by mass.

  The food or cosmetic composition of the present invention is an additive that imparts thickening action, gelling action, shape-retaining action, or dispersion stabilizing action, that is, thickener, gelling agent, shape-retaining agent, emulsifier or dispersion. It can also be used as a stabilizer.

The manufacturing method of the nanofiber of the citrus peel of this invention has the process of following (1) and (2), It is characterized by the above-mentioned.
(1) A step of pulverizing citrus peel into a paste,
(2) A step of defibrating the citrus peel paste obtained in step (1).

  The citrus peel used in step (1) is the same as described above. Prior to the pulverization treatment, the citrus peel may be subjected to treatments such as washing, draining and cutting.

  For the pulverization treatment, it is preferable to use citrus peel that has been previously immersed in water. By soaking in water, water-soluble pectin and the like are eluted, the cellulose content becomes relatively high, and nanofibers with higher viscosity can be prepared. Moreover, the component of a bittern can also be eluted and a bite can also be removed.

  In addition, a citrus peel that has been blanched can be used for crushing the citrus peel. In blanching, citrus peel is usually immersed in hot water at about 50 to 100 ° C. The blanching time is usually about 1 to 30 minutes, preferably about 5 to 15 minutes.

  For the pulverization treatment of citrus peel, it is preferable to use citrus peel mixed with a liquid such as water.

  The method for pulverizing the citrus peel is not particularly limited as long as the citrus peel can be made into a paste, and examples thereof include using a high-speed cutting stirrer. Examples of the high-speed cutting stirrer include Commitolol (registered trademark), a pulper finisher, an electric mill, a colloid mill, a food processor, a rotary cutter mill, and a micromeister. As a pulverization method, it is preferable to use comitolol. By using COMITOLOL, the number of defibrating treatments can be greatly reduced, and the defibrating treatment can be performed smoothly without clogging. Commitolol is preferably performed with an opening of 0.02 to 0.30 mm, and more preferably with an opening of 0.12 to 0.13 mm. By performing such a pulverization treatment, the target nanofiber can be prepared even if the number of times of the fibrillation treatment is reduced.

  In the step (1), further sterilization treatment, cooling treatment, and the like can be performed.

  The defibrating treatment in the step (2) is not particularly limited, and a known method can be used. For example, a stone mill type grinder (grinder, disc mill, grinder, etc.), a high-pressure homogenizer, a refiner (disc refiner). And conical refiners), biaxial extruders, water jet methods, underwater counter collision methods, bead mills, ball mills, microfluidizers and the like. The defibrating treatment is preferably a stone mill and a high-pressure homogenizer, and more preferably a high-pressure homogenizer in terms of efficiency. The pulverization pressure of the high-pressure homogenizer is preferably 20 to 200 MPa, more preferably 40 to 150 MPa, and still more preferably 50 to 100 MPa. The defibrating treatment can be performed by combining one type or two or more types.

  The solid content concentration of the citrus peel paste used when performing the defibrating treatment is preferably 0.5 to 10% by mass, more preferably 1 to 5% by mass.

  According to the method for producing nanofibers of citrus peel according to the present invention, the fiber width can be efficiently increased while maintaining the functionality of the peel without undergoing chemical treatment with enzymes or drugs or complicated manufacturing processes. It can be defibrated to the nano level.

  Furthermore, the nanofiber of the citrus peel of the present invention can improve the dispersibility of the fruit juice by adding to the fruit juice, and further has a high water absorption when it is in the form of a dry powder.

  Examples are given below to illustrate the present invention in more detail. However, the present invention is not limited to these examples. In the examples, fruit skin means outer skin and mesodermal skin unless otherwise specified.

<Example 1>
400 g of Kawachi citrus peel was hydrothermally treated at 120 ° C. for 10 minutes, crushed with a spatula, and then converted into nanofibers under the following treatment conditions.

-Disc mill condition use device: Masuyuki Co., Ltd. Supermass colloider (model number: MKCA6-2)
Disc type used: GC6-120
Rotation speed: 1800rpm
Clearance conditions: 1st 300-400μm, 2nd 300μm, 3rd 250μm, 4th 200μm, 5th 200μm, 6th 180μm
* The clearance setting method was defined as a clearance of 300μm, with the scale dial set to 3 at the position where the upper and lower discs touched each other. The scale dial was further narrowed from that position, and the short scale was set to 10 μm to obtain the clearance value.

・ Sample preparation method for SEM observation
(i) Kawachi late citrus peel nanofibers diluted about 1000 times with distilled water (solid content of about 0.005%) were filtered using 0.1 μm filter paper (ADVANTEC H010A025A).
(ii) After filtration, the filter paper was washed with ethanol, transferred to a petri dish filled with ethanol, ethanol was discarded, and the petri dish was refilled with ethanol.
(iii) The ethanol in the petri dish was discarded and replaced with t-butyl alcohol five times.
(iv) After substituting with t-butyl alcohol, it was frozen in a refrigerator.
(v) After freezing, the petri dish was warmed, the filter paper was cut into 5 mm squares with a scalpel, transferred to a freeze-drying cup, and freeze-dried.
(vi) The filter paper after lyophilization was attached to a plate for SEM, and the plate was osmium-deposited to prepare an observation sample.

  As a result, it was confirmed by SEM images that nanofibers were formed (FIG. 1). As a result of analyzing samples of the functional components derived from the peel for each machine treatment, there was almost no loss of functional components during the process of the machine treatment, and it was confirmed that the functionality was retained (Fig. 2). ).

<Example 2>
About 4.5 L of Kawachi citrus peel treated with boiling water for 10 minutes and then coarsely pulverized with a food processor was subjected to a disk mill treatment in the same manner as in Example 1 under the following treatment conditions. When measuring the viscosity, it was diluted to 95% water.
Clearance conditions: 1st 250 μm, 2nd 180 μm, 3rd 150 μm, 4th 150 μm

  As a result, it was confirmed by the measurement with the viscometer (DV-III Ultra, manufactured by Brookfield: Spindle, V-73) under the measurement conditions shown in Table 1 that the peels progressed and the viscosity increased with each treatment. (Fig. 3).

<Example 3>
After the Kawachi citrus peel was treated in boiling water for 10 minutes, it was exposed to water for 24 hours and roughly crushed with a food processor, and approximately 4.5 L was subjected to a disc mill treatment in the same manner as in Example 1 under the following treatment conditions. . When measuring the viscosity, it was diluted to 97% water.
Clearance conditions: 1st 250 μm, 2nd 180 μm, 3rd 150 μm, 4th 150 μm

  As a result, it was confirmed by the measurement with a viscometer that the defibration of the skin progressed and the viscosity increased each time it was processed (FIG. 4), and the viscosity was 3% even though the solid content was 3% lower than in Example 2. It was about the same. This is presumably because water-soluble pectin and the like were eluted by exposure to water, and the cellulose content was relatively high.

  Next, constituent sugars and galacturonic acid were analyzed in order to grasp the change in the composition of cellulose and the like due to water exposure of the skin.

(1) Analysis of ethanol / toluene extract Put 180 ml of ethanol / toluene solution (1: 2) in a round bottom flask, weigh approximately 1 g of each sample on a cylindrical filter paper, and dissolve in a solvent using a 6h Soxhlet extractor. The components were extracted, the samples before and after extraction were precisely weighed, and the amount of ethanol / toluene extract was calculated. The residue after extraction was used for subsequent analysis of constituent sugars and galacturonic acid.

(2) Analysis of Constituent Sugar Constituent sugar contained in citrus nanofiber paste was performed according to Laboratory analytical Procedure (Sluiter, A. et al., Technical report NREL / TP-510-42618 (2012)). To 50 mg of the dried sample, 600 μL of a 72% sulfuric acid solution was added and stirred at 30 ° C. for 1 hour. Then, it diluted with 16.8 mL distilled water, and hydrolyzed at 120 degreeC for 1 hour using the autoclave. After the hydrolysis treatment, the sample was neutralized with calcium carbonate, and neutral sugars contained in the sample were measured with a high-performance liquid chromatograph and a differential refractometry detector.

-High- performance liquid chromatographic measurement conditions Column oven temperature: 80 ° C, flow rate: 0.6 mL / min, mobile phase: ultrapure water column: HPX-87P, 300 mm x 7.8 mm, Bio-Rad Laboratories Inc., USA

(3) Analysis of galacturonic acid Pectin which is polygalacturonic acid contained in the citrus nanofiber paste was decomposed into galacturonic acid as a monomer by pectinase (from Aspergillus niger, Sigma-Aldrich Co. LLC, USA). 20 mg of sample and 10 mg of enzyme were added to 25 mL of acetate buffer (pH 4.0) and stirred for 2 days in a 50 ° C. incubator. After the enzyme treatment, galacturonic acid was measured by a high performance liquid chromatograph and a differential refractometry detector.

-High-performance liquid chromatographic measurement conditions Column oven temperature: 60 ° C, flow rate: 0.6 mL / min, mobile phase: 5 mM sulfuric acid column: HPX-87H, 300 mm x 7.8 mm, Bio-Rad Laboratories Inc., USA

  The cellulose concentration can be converted by multiplying the result of glucose concentration by 0.9.

  As shown in Table 2, it was confirmed from the constituent sugar glucose that about 15% and 22% of cellulose existed in the Kawauchi citrus peel nanofibers with and without water exposure, respectively. It was confirmed that the amount of cellulose was relatively increased by the amount of ethanol / toluene extract decreased by water exposure.

<Example 4>
Furthermore, by examining the pre-treatment method of raw materials, an efficient nano-treatment technology using only mechanical treatment was examined.

The raw citrus peel used was a Kawauchi citrus peel that was discharged from the juicer during fruit juice squeezing, drained, and then cut into approximately 1 cm square using a dicer. Next, it was blanched at 95 ° C. for 10 minutes, and after cooling with water, draining was performed. The same amount of water was added to the diced pericarp, and a 0.12 mm comitotrol treatment was performed, followed by sterilization and cooling to produce a Kawachi late citrus peel paste. About this paste sample 4 L, the disc mill process was implemented similarly to Example 1 on the process conditions shown below. When measuring the viscosity, it was diluted to 97% moisture.
Clearance conditions: 1st 150μm

  As a result, it was confirmed by the measurement with a viscometer that the peel was advanced and the viscosity was increased by only one treatment (FIG. 5).

<Example 5>
After the Kawachi citrus peel was treated in boiling water for 10 minutes and then coarsely pulverized by a food processor, a disk mill treatment was carried out in the same manner as in Example 1 under the following treatment conditions. The resulting three-time-treated paste was freeze-dried (dielectric freezer, -30 ° C), shelf-dried 60 ° C, or dried with a drum dryer (120 ° C), and after the solution was dispersed again to a moisture concentration of 95%, the viscosity was measured. did.
Clearance conditions: 180 μm for the first time, 150 μm for the second time, 150 μm for the third time

  As a result, it was confirmed by the measurement with a viscometer that the viscosity recovered by about 70% by shelf drying at 60 ° C (Fig. 6).

<Example 6>
The Kawauchi citrus peel was treated in boiling water for 10 minutes, then exposed to water for 22 hours, and coarsely pulverized by a food processor, and then subjected to disk mill treatment in the same manner as in Example 5. The obtained three-time-treated paste was diluted to a moisture concentration of 97%, frozen at -20 ° C, -30 ° C, and -80 ° C, and the viscosity was measured after thawing.

  As a result, it was confirmed that the viscosity was recovered by 50% or more, and that the recovery of the viscosity tended to increase as the freezing temperature decreased (FIG. 7).

<Example 7>
The paste sample used in Example 4 was treated three times at a pressure of 75 MPa and twice at a pressure of 150 MPa using a high-pressure homogenizer (Panda PLUS 2000, manufactured by GEA Nisosoavi). When measuring the viscosity, it was diluted to 97% water. As a result, it was confirmed by measurement with a viscometer that the viscosity increased as the number of treatments increased, and the viscosity increased as the treatment pressure increased (FIGS. 8 and 9).

  Moreover, as a result of analyzing the functional component for each treatment, most functional components were retained as shown in Table 3.

  Further, the obtained sample was prepared by the following method and observed with an atomic force microscope (JSPM-5200, manufactured by JEOL, hereinafter AFM). As a result, it was defibrated to the nano level as shown in FIG. The fiber width was about 2-5 nm. These results can be confirmed in the same way for Iyokan, Unshu oranges, and Ponkan. The average of the widths of the 20 fibers analyzed by the AFM observation was tabulated. As a result, fibers with a width of 2 to 10 nm were confirmed. As shown in Table 4, the average width was about 2 to 5 nm. In addition, after pulverizing the Kawachi evening citrus membrane using a food processor and treating it three times with a high-pressure homogenizer at a pressure of 75 MPa, fibers with an average of around 3 nm were observed for each treatment as shown in Table 4. It was done.

・ Method of pretreatment of aurapten in nanofiber
(1) About 0.1 g of lyophilized sample was weighed into a plastic centrifuge tube (50 ml), 15 ml of acetone was added, and ultrasonic extraction was performed for 10 minutes.
(2) Filtration using 5C filter paper and washing with acetone and ethanol.
(3) Concentrated to 0.5 ml with a rotary evaporator and made up to 10 ml.
(4) The solution which was made up was used as a sample for analysis through a 0.2 μm filter.

・ Pretreatment method of flavanone and polymethoxyflavone in nanofiber
(1) About 0.05 g of a lyophilized sample was weighed, 5 ml of an extraction solvent (MeOH: DMSO = 1: 1) was added, mixed with a vortex mixer, subjected to ultrasonic extraction for 10 minutes, and left for 1 hour or more.
(2) After centrifugation at 10,000 rpm for 10 minutes, the supernatant was added to a measuring cylinder with a stopper.
(3) 1 ml of extraction solvent was added to the precipitate, mixed with a vortex mixer, and then subjected to ultrasonic extraction for 10 minutes.
(4) After centrifuging at 10,000 rpm for 10 minutes, the supernatant was added to the beaker of (2), 1 ml of extraction solvent was added to the precipitate, mixed again with a vortex mixer, and then subjected to ultrasonic extraction for 10 minutes.
(5) After centrifugation at 10,000 rpm for 10 minutes, the supernatant was taken into the beaker of (2), and distilled water was added to the extract combined with the supernatant so that the solvent concentration was 10% (V / V).
(6) The sample was passed through a solid-phase extraction disk (Bond Elut (C18, 500 mg)) conditioned sequentially with 3 ml of methanol and 6 ml of 10% (V / V) methanol.
(7) After washing with 15 ml of 10% (V / V) methanol, elution with 5 ml of extraction solvent, the volume was adjusted in a 5 ml volumetric flask, and passed through a 0.2 μm filter to obtain a sample for analysis.

・ Analysis conditions LC / MS system: ACQUITY UPLC, Waters Q-TOF micro
○ Column: BEH C18 (1.7μm, 2.1 mm x 100 mm)
○ Column temperature: 40 ℃
○ Detector: PDA
○ Mobile phase conditions, etc.
[Aurapten] Flow rate: 0.3 ml / min, 10 mM ammonium formate-containing water: Methanol = 25:75
[Polymethoxyflavone] Flow rate: 0.25 ml / min, 10 mM ammonium formate-containing water: Acetonitrile = 60:40
[Flavanone] Flow rate: 0.25 ml / min
Eluent A Acetonitrile
Eluent B 10 mM ammonium formate-containing water
Gradient conditions (eluent A): 80% (0 → 4 minutes), 80 → 60% (4 → 5 minutes), 60% (5 → 6 minutes), 60 → 30% (6 → 7 minutes), 30% (7 → 10 minutes), 30 → 80% (10 → 10.5 minutes), 80% (10.5 → 12 minutes)

・ Preparation before AFM observation・ Approximately 10 ml of diluted solution was prepared so as to be a 0.1% solid content solution.
-The above solution was further diluted 10 times, and 1.5 ml was prepared in a 2 ml centrifuge tube.
-Treated with 100 μA ultrasonic conditions for 30 seconds.
-A silicon wafer cut to about 5 mm square was immersed in 1% PEI (polyethyleneimine) for 10 minutes or more, washed with ultrapure water, then blown with N ₂ gas and dried. A silicon wafer was set on a spin coater, and 80 μl of a solution treated with ultrasonic waves was dropped on the substrate. After standing for 1 minute, the spin coater was started at 3000 rpm for 60 seconds to prepare an observation sample.

<Example 8>
The following nanofibers were added to Kawachi citrus finisher juice to a solid content concentration of 0.6% and further diluted 10-fold. This solution was measured every 2 minutes for a total of 30 minutes using a solution stability evaluation apparatus (TURBISCAN MA2000) (light source: pulsed LED 850 nm).
(1) Binfisu standard manufactured by Sugino Machine
(2) Kawachi late citrus outer skin mesocarp high pressure homogenizer treated nanofiber (150MPa 2 pass) (3) Kawachi late citrus capsule high pressure homogenizer treated nanofiber (75MPa 3 pass)

  As a result, the wood pulp-derived Vinfis standard started agglomeration earlier, while nanofibers derived from Kawachi late citrus pericarp mesocarp slightly aggregated, whereas nanofibers derived from gills did not aggregate at all. (FIG. 11).

<Example 9>
The sample of Example 7 in which each citrus peel paste was nano-processed with a high-pressure homogenizer was used immediately after rotating the spindle at 6 rpm for 1 minute using a B-type rotary viscometer (Brookfield DV-III Ultra). Viscosity measurement was performed, followed by viscosity measurement immediately after rotating the spindle for 1 minute at 60 rpm. The data after 1 minute was selected for each, and the TI value was calculated and shown in Table 5. As a result, these TI values were around 7, and it was found that they have a large thixotropic property.

The TI value was measured by the method prescribed in JISK5101-6-2 (pigment test method-6 parts: fluidity-Section 2: rotational viscometer method) and calculated by the following formula.
・ TI value = apparent viscosity at 6rpm / apparent viscosity at 60rpm

<Example 10>
Samples 1 and 2 in Table 6 were commercially available.

  Preparation of samples 3, 4 and 6 in Table 6: Each citrus peel was treated in boiling water for 10 minutes (sample 6 was exposed to water for 24 hours) and then coarsely pulverized with a food processor. Conducted once. Further, it was treated twice at 150 MPa using a high-pressure homogenizer, sterilized at 90 ° C. for 15 minutes, freeze-dried, and then roughly pulverized with a food processor.

  Preparation of sample 5 in Table 6: The paste sample used in Example 4 was treated twice at 150 MPa using a high-pressure homogenizer, sterilized at 90 ° C. for 15 minutes, and then freeze-dried. And coarsely pulverized with a food processor.

Measuring method of water absorption: 1.00 g of each powder of dried samples 1 to 6 was put in a 50 mL tube, 40 g distilled water was added, and the mixture was allowed to stand overnight at room temperature. After centrifuging the tube at 3000 rpm for 30 minutes, the supernatant was discarded, and the powder weight after water absorption (the total weight of the powder and the water absorbed in the powder) was measured. The water absorption was calculated by the following formula.
Water absorption (%) = (powder weight after water absorption-powder weight before water absorption (1.00 g)) / powder weight before water absorption (1.00 g) x 100

  The results are shown in Table 6. As a result of measuring the water absorption using each citrus peel dry powder, all the citrus-derived nanofibers had a water absorption of 1000% or more. In particular, Iyokan and Kawachi Bankan had a water absorption rate of over 2000%.

Claims (11)

2-10 nm wide citrus peel nanofibers,
A nanofiber having a thixotropic index of 2 to 10 when an aqueous dispersion having a solid content concentration of 0.5 to 10% by mass is obtained.   The nanofiber according to claim 1, further comprising at least one selected from the group consisting of aurapten, naringin, nariltin, hesperidin, sinensetin, nobiletin, heptamethoxyflavone, and tangeretin.   The citrus fruits are Kawachi Bankan, Unshu Mandarin, Ponkan, Kiyomi, Shiranui, Iyokan, Orange, Lemon, Lime, Eggplant, Sweet Summer, Hachiman, Bundan, Grapefruit, Kanpei, Atago Fruit Trial 28, Natsumikan, Setuka , Kara, Harumi, Harehime, Haruka, Nantsukai, Navel Orange, Amakusa, Marihime, Hyuga Summer, Tarocco, Daidai, Himetsuki, Encore, Seminole, Kavos, Moro, Jara, Tamami, Golden Citrus, Ansei Kan , Amakusa, Sudachi, Kumquat, Sweet Spring, Rei, Marcot, Tsunoka, Tomoko, Sakwasa, HimeAkari, Nishinoka, Sanhokan, Southern Yellow, Aiome, Chandra Pomero, Orange Hinata, Kishu Mandarin, Hayaka , Bumpeiyu, Yuko, Fukuhara Orange, Aurastar, and Buddha Tangerine. Nanofiber according to claim 1 or 2.   The nanofiber according to any one of claims 1 to 3, which is in a dry powder state or a frozen state.   The nanofiber according to any one of claims 1 to 4, which is in a dry powder form and has a water absorption rate of 1000% or more.   A food or cosmetic composition comprising the nanofiber according to any one of claims 1 to 5.   The composition of Claim 6 which is a thickener, a gelling agent, a shape retention agent, an emulsifier, or a dispersion stabilizer. The manufacturing method of the nanofiber of the citrus fruit peel which has the process of following (1) and (2):
(1) A step of pulverizing citrus peel into a paste,
(2) A step of defibrating the citrus peel paste obtained in step (1).   The manufacturing method according to claim 8, wherein in the step (1), the pulverization is performed with a high-speed shear stirrer.   In the step (2), the defibrating treatment is performed by a stone mill grinder, a high-pressure homogenizer, a refiner, a twin screw extruder, a water jet method, an underwater counter collision method, a bead mill, a ball mill, or a microfluidizer. The manufacturing method as described in.   The manufacturing method as described in any one of Claims 8-10 which uses the citrus peel previously immersed in the water in the said process (1).