JP2024008568A - Heat insulation method of water-containing liquid and oil and fat composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation method of a water-containing liquid which can suppress temporal temperature change of a water-containing liquid, and an oil and fat composition for use in the heat insulation method.

SOLUTION: A heat insulation method of a water-containing liquid includes a coating step of coating a part or all of a liquid surface of a water-containing liquid having a temperature difference with respect to a contact air temperature by an oil and fat composition containing 40-99.9 mass% of oil and fat, and 0.1-60 mass% of one or more emulsifiers selected from the following emulsifiers A, B and C. The emulsifier A: sucrose fatty acid ester where 50 mass% or more of a constituent fatty acid is an unsaturated fatty acid. The emulsifier B: polyglycerol condensed recinoleic acid ester. The emulsifier C: an emulsifier having an HLB of 3 to 8.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a method for keeping a water-containing liquid warm, and an oil and fat composition for use in the heat keeping method.

Water-containing liquids that have a predetermined temperature different from room temperature, such as cold or hot water for drinking purposes, drinks taken out of the refrigerator, green tea in a teapot, or hot water in a bathtub, change to room temperature over time. It is desired that these water-containing liquids having a predetermined temperature be kept at that temperature for a long period of time.

As a method for keeping a water-containing liquid warm, methods disclosed in Patent Documents 1 and 2 are known.

Patent Document 1 states that when virgin olive oil is added to a water-based liquid, it spreads over the surface of the liquid and forms a thin oil film, thereby controlling the temperature change of the liquid over time with a small amount compared to other edible oils. It has been disclosed that it can be suppressed.

Additionally, Patent Document 2 states that when oil, including roasted cooking oil, is added to a water-based liquid, it spreads over the liquid surface to form a thin oil film, thereby reducing the amount of liquid in a small amount compared to other cooking oils. It is disclosed that temperature changes over time can be suppressed.

Japanese Patent Application Publication No. 2013-116076 Japanese Patent Application Publication No. 2013-183638

Virgin olive oil and roasted cooking oil are relatively expensive, so it is desirable to have a heat retention method that can use not only these expensive oils but also relatively inexpensive fats and oils to keep water-containing liquids warm. It will be done.

An object of the present invention is to provide a method for keeping a water-containing liquid warm that can suppress temperature changes over time in a water-containing liquid, and an oil and fat composition for use in the heat-keeping method. In addition, "heat retention" in the present invention means suppressing (delaying) the temperature change (temperature decrease or temperature increase) of the water-containing liquid over time to the contact air temperature.

In order to achieve the above object, the present invention provides the following method for keeping a water-containing liquid warm, an oil and fat composition for use in the heat-keeping method, and a method for increasing the proportion of water-containing liquid that covers the liquid surface (liquid surface occupancy). I will provide a.

In the present invention, the description of X (numerical value) to Y (numeric value) means X or more and Y or less, unless otherwise specified.

[1] By an oil and fat composition containing 40 to 99.9% by mass of fats and oils and 0.1 to 60% by mass of one or more emulsifiers selected from the following emulsifiers A, B, and C. A method for keeping a water-containing liquid warm, which includes a step of covering part or all of the surface of the water-containing liquid that has a temperature difference with respect to the contact air temperature.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleic acid ester Emulsifier C: Emulsifier with HLB 3 to 8 [2] The coating step is performed on the oil and fat composition. The heat retention method according to [1] above, which is a step of covering 20% or more of the area of the liquid surface.
[3] In the coating step, the amount of the oil and fat composition added (g)/area of the liquid surface (cm ² ) is 0.007 or more (g/cm ² ) in the water-containing liquid. The heat retention method according to [1] or [2], which includes the step of adding the water-containing liquid to the oil composition or the step of adding the water-containing liquid to the oil and fat composition in the amount.
[4] The heat retention method according to any one of [1] to [3] above, wherein the water-containing liquid has a temperature higher than the contact air temperature.
[5] The heat retention method according to any one of [1] to [4], wherein the water-containing liquid has a temperature difference of 5° C. or more with respect to the contact air temperature.
[6] The heat retention method according to any one of [1] to [5] above, wherein the oil and fat composition contains the emulsifier A.
[7] The heat retention method according to any one of [1] to [6], wherein the oil and fat composition contains the emulsifier B.
[8] The heat retention method according to any one of [1] to [7] above, wherein the oil and fat composition contains the emulsifier C.
[9] The heat retention method according to [8], wherein the emulsifier C is one or more selected from polyglycerin fatty acid ester, organic acid monoglyceride, sorbitan fatty acid ester, and propylene glycol monoester.
[10] The heat retention method according to any one of [1] to [9] above, wherein the fat or oil is a refined vegetable oil.
[11] The oil and fat composition according to any one of [1] to [10] above for use in the heat retention method according to any one of [1] to [10] above.
[12] A method for increasing the proportion of the liquid surface of a water-containing liquid covered by an oil-fat composition (liquid surface occupancy), wherein the oil-fat composition contains 40 to 99.9% by mass of oil and fat, and the following emulsifier A: A method in which the oil and fat composition contains 0.1 to 60% by mass of one or more emulsifiers selected from Emulsifier B and Emulsifier C.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleate ester Emulsifier C: Emulsifier with HLB 3 to 8

According to the present invention, it is possible to provide a method for keeping a water-containing liquid warm that can suppress temperature changes over time of the water-containing liquid, and an oil and fat composition for use in the heat-keeping method.

FIG. 2 is a diagram showing the results of Test 2.

[How to keep water-containing liquid warm]
A method for keeping a water-containing liquid warm according to an embodiment of the present invention (hereinafter referred to as "the present embodiment") includes 40 to 99.9% by mass of oil and fat, and 1 selected from the following emulsifiers A, B, and C. A coating step in which part or all of the liquid surface of a water-containing liquid having a temperature difference with respect to the contact air temperature is covered with an oil composition containing 0.1 to 60% by mass of seeds or two or more emulsifiers. including.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleate ester Emulsifier C: Emulsifier with HLB 3 to 8

(Coating process)
The method for keeping a water-containing liquid warm according to the present embodiment includes a coating step of covering part or all of the liquid surface of the water-containing liquid, which has a temperature difference with respect to the contact air temperature, with a predetermined oil and fat composition.

A water-containing liquid is a liquid containing water, preferably a liquid containing 50% by mass or more of water, more preferably a liquid containing 60% by mass or more of water, and more preferably 70% by mass or more of water. , more preferably a liquid containing 80% by mass or more of water, still more preferably a liquid containing 90% by mass or more of water, and most preferably a liquid containing 95% by mass or more of water. . Examples of the water-containing liquid include beverages such as cold water, hot water, ginger water, lemonade, yuzu soup, cocoa, soup drinks, tea, alcoholic drinks, carbonated drinks, etc.; or bath water. Particularly preferred are drinks that have a body temperature retaining effect, such as ginger tea, hot lemonade, yuzu soup, and cocoa. Beverages that have a body temperature warming effect refer to drinks that are known to have the effect of warming the body, for example, by improving blood circulation. In this specification, "beverage" refers not only to beverages consisting only of liquid (including cases containing solids dissolved in water), but also to drinks consisting of liquid and solids not dissolved in water. Includes drinks and soups in foods and drinks, such as soup drinks consisting of liquid soup and ingredients (e.g. corn soup, minestrone, etc.), soup drinks (e.g. noodle soup such as ramen, udon, somen, soba, etc.), miso soup , kenchin soup, pork soup, sweet potato soup, shiruko, etc.), and porridge. The solid content dissolved in water includes, for example, powder or extract that is the base of beverages, specifically, powder that is the base of ginger tea, cocoa powder, powder that is the base of soup drinks, concentrated juice, sugars, Examples include salt, soy sauce, wheat flour, starch, polysaccharide thickener, soluble spices, vegetable powder, amino acids, vitamins, antioxidants, and coloring agents. Solids that are not dissolved in water include solid ingredients such as soup drinks and juice drinks, specifically vegetables, grains, fruits, meat, chicken, seafood, eggs, etc., and processed products of these (menma). , kamaboko, tofu, noodles, etc.), solid spices, etc. If the beverage contains solids that are not dissolved in water, the water content of the water-containing liquid is calculated excluding the mass of the solids.

Water-containing liquids are stored in suitable containers, and in the case of beverages, containers include pots, pots, frying pans, mugs, teacups, teacups, bowls, tea bowls (rice bowls), soup bowls, cans, bottles, and water bottles. Examples include. Examples of containers for hot water for bathing include household bathtubs and bathtubs in bathing facilities (public baths, spas, hot springs, heated pools, etc.). The material of the container is not particularly limited, but examples include ceramics, resin, heat-resistant glass, metal, wood, stone, rock, concrete, etc., and containers made of materials with low thermal conductivity (thermal conductivity) are preferable. .

The water-containing liquid having a temperature difference with respect to the contact air temperature may be at any temperature, but preferably 5 °C or more, 10 °C or more, 15 °C or more with respect to the contact air temperature (for example, 20 °C) , 20℃ or higher, 25℃ or higher, 30℃ or higher, 35℃ or higher, 40℃ or higher, 45℃ or higher, 50℃ or higher, 55℃ or higher, 60℃ or higher, 65℃ or higher, 70℃ or higher, 75℃ or higher, 80 It has a temperature difference of 85°C or more, or 90°C or more. That is, it has a temperature that is 5 to 90°C or more higher than the contact air temperature or 5 to 90°C or more lower than the contact air temperature. Further, the water-containing liquid preferably has a temperature higher than the contact air temperature, and more preferably has a temperature higher than the contact air temperature by at least the above temperature difference. If the water-containing liquid is a beverage, it may be a cold beverage at 0-10°C or a hot beverage at 80-100°C, for example. Note that the contact air temperature means, for example, the room temperature or outside temperature at a production site or a supply site of a water-containing liquid, a bathroom, etc., and the gas temperature in a closed container such as a water bottle.

The coating step is a step of covering part or all of the liquid surface of the water-containing liquid with a predetermined oil and fat composition, and the covering step is a step of covering part or all of the liquid surface of the water-containing liquid with a predetermined oil and fat composition. Preferably, the step covers 60% or more, 70% or more, 80% or more, 90% or more, or 100%. Liquid level means the level of a hydrous liquid that is in contact with the surrounding air.

In the coating step, the amount (g) of the predetermined fat composition added/the area (cm ² ) of the liquid surface of the water-containing liquid is 0.005 or more, 0.007 or more, 0.01 or more, 0.02 or more, 0. 03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, 0.09 or more, 0.1 or more, 0.11 or more, 0.12 or more, 0. It is preferable to include a step of adding a predetermined fat composition in an amount of 13 or more or 0.14 or more (g/cm ² ) to a water-containing liquid, or a step of adding a water-containing liquid to the predetermined fat composition in the amount. The upper limit of the amount added is not particularly limited, but it is preferable to obtain a high heat retention effect with a smaller amount, so it is 0.3 or less, 0.2 or less, 0.18 or less, 0.16 or less, 0. It is preferably 15 or less or 0.14 or less (g/cm ² ).

The predetermined oil and fat composition used in the heat retention method according to the present embodiment contains 40 to 99.9% by mass of oil and fat, and one or more emulsifiers selected from the following emulsifier A, emulsifier B, and emulsifier C. Contains 0.1 to 60% by mass.

(Oils and fats)
In this embodiment, as the oil and fat, animal and vegetable oils, oils and fats synthesized from glycerin and fatty acids, fractionated oils thereof, transesterified oils, hydrogenated oils, etc. can be used alone or in combination. Examples of animal oils include beef tallow, milk fat, and fish oil, and include soybean oil, high-oleic soybean oil, rapeseed oil, high-oleic rapeseed oil, cottonseed oil, sunflower oil, high-oleic sunflower oil, safflower oil, high-oleic safflower oil, corn oil, It is preferable to use vegetable oils such as rice oil, sesame oil, olive oil, perilla oil, flaxseed oil, peanut oil, grape seed oil, coconut oil, palm kernel oil, and palm oil. Examples of fats and oils synthesized from glycerin and fatty acids include medium chain fatty acid triglycerides (MCT). Examples of the fractionated oil include fractionated oils of palm oil such as palm olein, palm super olein, palm stearin, and palm midfraction. As the transesterified oil, transesterified oil of palm oil or fractionated oil of palm oil and other liquid fats and oils, or transesterified oil of MCT and vegetable oil, etc. can be used. Examples of hydrogenated oils include hydrogenated oils such as animal and vegetable oils and fractionated oils of animal and vegetable oils, as well as hydrogenated oils such as transesterified oils. Although unrefined fats and oils may be used, it is preferable to use refined fats and oils.

The content of fat and oil in the fat and oil composition is 40 to 99.9% by mass. The lower limit of the oil and fat content is preferably 48% by mass, more preferably 78% by mass, 88% by mass, 93% by mass, or 98% by mass. Further, the upper limit of the oil and fat content is preferably 99.6% by mass, more preferably 99.2% by mass, 92% by mass, 82% by mass, or 52% by mass.

(Emulsifier A)
In one embodiment, the oil and fat composition contains emulsifier A below.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids

The sucrose fatty acid ester in this embodiment is an esterified product of sucrose and a linear fatty acid having 8 to 24 carbon atoms, and 50% by mass or more of the constituent fatty acids are unsaturated fatty acids, but 60 to 100% of the constituent fatty acids are unsaturated fatty acids. It is preferred that % by mass is unsaturated fatty acids, and more preferably 70 to 100% by mass is unsaturated fatty acids. As the unsaturated fatty acid, oleic acid and erucic acid are preferred, and oleic acid is more preferred. Among linear fatty acids having 8 to 24 carbon atoms, fatty acids other than unsaturated fatty acids are saturated fatty acids, and palmitic acid and stearic acid are preferred. As the sucrose fatty acid ester, a commercially available product may be used, or one produced by a conventionally known method may be used. As a commercially available product, for example, Ryoto Sugar Ester O-170 manufactured by Mitsubishi Chemical Corporation can be used as appropriate. Two or more types of sucrose fatty acid esters may be used in combination.

Sucrose fatty acid esters with HLB of 0 to 5 are preferred, sucrose fatty acid esters with HLB of 0 to 3.5 are more preferred, sucrose fatty acid esters with HLB of 0.5 to 2 are still more preferred, and HLB is 0.5. ˜1.5 sucrose fatty acid esters are most preferred. Note that HLB is an abbreviation for Hydrophile-Hydrophobic Balance, and is an indicator of whether an emulsifier is hydrophilic or lipophilic, and takes a value of 0 to 20. The smaller the HLB value, the stronger the lipophilicity. In the present invention, HLB is calculated using the atlas method. In the atlas method, HLB is calculated using the following formula.
HLB=20×(1-S/A)
S: Saponification value A: Neutralization value of fatty acid in ester

(Emulsifier B)
In one embodiment, the oil and fat composition contains the following emulsifier B.
Emulsifier B: Polyglycerin condensed ricinoleate ester

As the polyglycerin condensed ricinoleate ester, a commercially available product may be used, or one produced by a conventionally known method may be used. Commercially available products include, for example, SY Glister CR-310, CR-500, CR-ED, and CRS-75 manufactured by Sakamoto Pharmaceutical Co., Ltd., and Sunsoft No. manufactured by Taiyo Kagaku Co., Ltd. 818DG, 818R, 818SK, 818H, Poem PR-300, PR-400 manufactured by Riken Vitamin Co., Ltd., etc. can be used as appropriate. Two or more types of polyglycerin condensed ricinoleate esters may be used in combination.

A polyglycerin condensed ricinoleate ester having an HLB of less than 3 is preferred, a polyglycerin condensation ricinoleate ester having an HLB of 0 to 2 is more preferred, and a polyglycerin condensation ricinoleate ester having an HLB of 1 to 2 is even more preferred.

Further, polyglycerin condensed ricinoleic acid esters having an average degree of polymerization of 4 to 12 are preferred, and polyglycerin condensed ricinoleic acid esters having an average degree of polymerization of 4 to 10 are more preferred. Note that polyglycerin is produced by polymerizing glycerin, and is obtained as a mixture having various degrees of polymerization. Generally, it is difficult to isolate polyglycerin having a degree of polymerization of 4 or more, so the present invention also allows the polyglycerin structure to be a mixture of various degrees of polymerization. Therefore, in the present invention, the degree of polymerization is the average degree of polymerization in the polyglycerin structure. The degree of polymerization can be calculated, for example, from the following relational expression of the hydroxyl value (OHV), the degree of polymerization (n), and the molecular weight (MW).
MW=74n+18
OHV=56110(n+2)/MW

(Emulsifier C)
In one embodiment, the oil and fat composition contains the following emulsifier C.
Emulsifier C: Emulsifier with HLB 3 to 8

Emulsifier C is an emulsifier with an HLB of 3 to 8, preferably an emulsifier with an HLB of 3 to 5.5 or 6 to 8, more preferably an emulsifier with an HLB of 3 to 5 or 6.5 to 8, and an emulsifier with an HLB of 3 to 5. More preferably, it is an emulsifier of 5 to 5 or 6.5 to 7.5.

The emulsifier C is preferably one or more selected from polyglycerin fatty acid ester, organic acid monoglyceride, sorbitan fatty acid ester, and propylene glycol monoester.

The polyglycerin fatty acid ester is preferably one in which 71% by mass or more of the constituent fatty acids are unsaturated straight chain fatty acids having 16 to 22 carbon atoms, and 75 to 100% by mass of the constituent fatty acids are unsaturated straight chain fatty acids having 16 to 22 carbon atoms. Saturated straight chain fatty acids are more preferred, and 80 to 100% by mass of the constituent fatty acids are unsaturated straight chain fatty acids having 16 to 22 carbon atoms. Examples of unsaturated straight chain fatty acids having 16 to 22 carbon atoms include palmitooleic acid, oleic acid, linoleic acid, linolenic acid, erucic acid, etc., and it is preferable that the fatty acid is one or more selected from these. Preferably, oleic acid and/or erucic acid are more preferable. The constituent fatty acids other than the unsaturated straight chain fatty acids having 16 to 22 carbon atoms are not particularly limited, but saturated straight chain fatty acids having 6 to 22 carbon atoms can be used, such as caproic acid, caprylic acid, capric acid, etc. , lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, etc., and preferably one or more selected from these, with palmitic acid and/or stearic acid being more preferred. As the polyglycerol fatty acid ester, a commercially available product may be used, or one manufactured by a conventionally known method may be used. Commercially available products include, for example,
Poem DO-100V manufactured by Riken Vitamin Co., Ltd., Sunsoft Q-1710S and Sunsoft Q-175S manufactured by Taiyo Kagaku Co., Ltd., etc. can be used as appropriate. Two or more types of polyglycerin fatty acid esters may be used in combination.

Polyglycerin fatty acid esters having an average degree of polymerization of 2 to 12 are preferred, polyglycerin fatty acid esters having an average degree of polymerization of 2 to 8 are more preferred, and polyglycerin fatty acid esters having an average degree of polymerization of 2 to 6 are even more preferred.

Examples of the organic acid monoglyceride include citric acid monoglyceride, succinic acid monoglyceride, lactic acid monoglyceride, acetic acid monoglyceride, and tartaric acid monoglyceride. Preferred are citric acid monoglyceride and succinic acid monoglyceride. Note that 50% by mass or more of the fatty acids constituting the organic acid monoglyceride is preferably an unsaturated fatty acid having 16 to 22 carbon atoms, more preferably oleic acid, linoleic acid, linolenic acid, or erucic acid, and oleic acid , more preferably erucic acid. As the organic acid monoglyceride, a commercially available product may be used, or one produced by a conventionally known method may be used. As a commercially available product, for example, Sunsoft No. manufactured by Taiyo Kagaku Co., Ltd. 623M etc. can be used as appropriate. Two or more types of organic acid monoglycerides may be used in combination.

As propylene glycol monooleate, a commercially available product may be used, or one produced by a conventionally known method may be used. As a commercially available product, for example, Rikemar PO-100V manufactured by Riken Vitamin Co., Ltd. can be used as appropriate.

Sorbitan fatty acid esters are monoesters, diesters, or triesters of sorbitan and fatty acids produced by intramolecular dehydration of sorbitan. The sorbitan fatty acid ester used in this embodiment preferably has a fatty acid having 12 to 24 carbon atoms, and more preferably oleic acid or stearic acid. As the sorbitan fatty acid ester, a commercially available product may be used, or one produced by a conventionally known method may be used. As a commercially available product, for example, Poem O-80V manufactured by Riken Vitamin Co., Ltd. can be used as appropriate. Two or more types of sorbitan fatty acid esters may be used in combination.

Examples of other emulsifiers C include monoglycerides.
As monoglycerides, for example, 50% by mass or more of the constituent fatty acids are preferably unsaturated fatty acids having 16 to 22 carbon atoms, more preferably oleic acid, linoleic acid, linolenic acid, and erucic acid; More preferably, it is erucic acid. As the monoglyceride, a commercially available product may be used, or one manufactured by a conventionally known method may be used. As a commercially available product, for example, Sunsoft No. manufactured by Taiyo Kagaku Co., Ltd. 700P-2, Sunsoft No. 750, Emulgy MU manufactured by Riken Vitamin Co., Ltd., etc. can be used as appropriate. Two or more monoglycerides may be used in combination.

The (total) content of one or more emulsifiers selected from the above-mentioned emulsifier A, emulsifier B, and emulsifier C in the oil and fat composition is 0.1 to 60% by mass. The lower limit of the emulsifier content is preferably 0.4% by mass, more preferably 0.8% by mass, 8% by mass, 18% by mass, or 48% by mass. Further, the upper limit of the emulsifier content is preferably 52% by mass, more preferably 22% by mass, 12% by mass, 7% by mass, or 2% by mass.

The oil and fat composition may contain emulsifiers other than the above-mentioned emulsifiers A to C to the extent that the effects of the present invention are not impaired. Other emulsifiers include, for example, sorbitol fatty acid esters, propylene glycol fatty acid esters, polysorbates, and the like. The content of these emulsifiers can be any amount as long as it does not impair the effects of the present invention, but for example, it can be contained in the oil and fat composition at 10% by mass or less, preferably from 0 to 3% by mass. , more preferably 0 to 1% by mass.

(Other components in the oil and fat composition)
Other components of the oil and fat composition include oil and fat soluble components, specifically antioxidants such as tocopherol, silicone oil, and the like.

[Oil composition]
The oil and fat composition according to the present embodiment is any of the predetermined oil and fat compositions detailed in the above-described present embodiment for use in the heat retention method according to the above-described present embodiment.

[Method of increasing the proportion of water-containing liquid that covers the liquid surface (liquid surface occupancy rate)]
The method of increasing the proportion of the surface of the hydrous liquid (liquid surface occupancy) according to the present embodiment is a method of increasing the proportion of the surface of the hydrous liquid covered by the oil/fat composition (liquid surface occupancy), which comprises: The fat composition contains 40 to 99.9% by mass of fats and oils, and 0.1 to 60% by mass of one or more emulsifiers selected from the following emulsifiers A, B, and C: It is a thing, a method.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleate ester Emulsifier C: Emulsifier with HLB 3 to 8

The definition of each term, the type and content of each component, etc. in the method of increasing the proportion of the surface of the water-containing liquid (liquid surface occupancy) according to the present embodiment are explained in the method for keeping the water-containing liquid warm according to the present embodiment. As explained.

Next, the present invention will be explained with reference to Examples, but the present invention is not limited to these Examples.

(Manufacture of oil and fat composition)
An oil and fat composition was produced by mixing raw materials according to the formulations (mass%) shown in Tables 1 and 2. The raw materials used are as follows.
Refined rapeseed oil (product name: Nissin Canola Oil, manufactured by Nissin Oilio Group Co., Ltd.)
Sucrose oleate ester (trade name “Ryoto Sugar Ester O-170”, manufactured by Mitsubishi Chemical Corporation, HLB approx. 1)
Pentaglycerin condensed ricinoleate ester (trade name "Sunsoft No. 818R", manufactured by Taiyo Kagaku Co., Ltd., HLB less than 3)
Hexaglycerin condensed ricinoleate ester (product name "PR-400", manufactured by Riken Vitamin Co., Ltd., HLB less than 3)
Propylene glycol monooleate (“Rikemar PO-100V”, manufactured by Riken Vitamin Co., Ltd., HLB3.6)
Diglycerin monooleate (trade name "Poem DO-100V", manufactured by Riken Vitamin Co., Ltd., HLB7.3)
Decaglycerin decaoleate (trade name "Sunsoft Q-1710S", manufactured by Taiyo Kagaku Co., Ltd., HLB3)
Organic acid monoglyceride (glycerin citric acid monooleate, trade name "Sunsoft No. 623M", manufactured by Taiyo Kagaku Co., Ltd., HLB7)
Sorbitan fatty acid ester (sorbitan oleate, trade name "Poem O-80V", manufactured by Riken Vitamin Co., Ltd., HLB4.9)
<Used in comparative examples below>
Sucrose stearate 1 (trade name "Ryoto Sugar Ester S-170", manufactured by Mitsubishi Chemical Corporation, HLB approx. 1)
Sucrose stearate 2 (trade name "Ryoto Sugar Ester S-1670", manufactured by Mitsubishi Chemical Corporation, HLB16)

(Test 1)
A container containing 25 g of soy sauce and 5 g of purified rapeseed oil (Comparative Example 1) or 5 g of each of the produced oil and fat compositions (Examples 1 to 15, Comparative Examples 2 to 3), or a container containing only 25 g of soy sauce (Reference Example) ), 300 g of boiling water was added, and the starting temperature (approximately 82 to 85°C) immediately after the addition was measured. The mixture was left at room temperature (20°C), and the temperature was measured 15 minutes after the addition. Tables 1 and 2 show the starting temperature, the temperature after 15 minutes, and the temperature difference (starting temperature - temperature after 15 minutes).
The surface area of the soy sauce water surface (the upper surface exposed to the outside air) in the container is 153.9 cm ² , and the amount of fat or oil composition added per 1 cm ² of area is 5/153.9 ≒ 0.032 g/ It was ^cm2 .

(Test 2)
Add 300 g of boiling water (about 100 ° C.) to a container containing the purified rapeseed oil of Comparative Example 1 or the oil and fat composition (1.1 g, 2.2 g, 5.4 g, or 22 g) produced in Example 2, It was left at room temperature (20°C). Ten minutes after the addition, the diameter of the oil film on the water surface and the approximate area of the oil film were measured or calculated by the following method, and the liquid surface occupancy rate (=approximate area of oil film/surface area of water surface) was calculated. The measurement results and calculation results are shown in Table 3.
The surface area of the water surface (the upper surface exposed to the outside air) in the container was 153.9 cm ² , and the amount of oil or fat composition added per 1 cm ² of area was as shown in Table 3.
<Measurement method of oil film diameter>
Ten minutes after the addition, the oil and fat composition had formed an oil film in a nearly perfect circle, and the diameter (2r) of the oil film on the water surface was measured with a ruler.
<How to calculate the approximate area of the oil slick>
The approximate area of the oil film on the water surface was calculated (πr ² ) assuming that the oil film is a perfect circle.

Claims (12)

An oil or fat composition containing 40 to 99.9% by mass of fats and oils and 0.1 to 60% by mass of one or more emulsifiers selected from the following emulsifier A, emulsifier B, and emulsifier C can reduce contact air. A method for keeping a water-containing liquid warm, which includes a coating step of covering part or all of the surface of the water-containing liquid that has a temperature difference.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleate ester Emulsifier C: Emulsifier with HLB 3 to 8 The heat retention method according to claim 1, wherein the covering step is a step of covering 20% or more of the area of the liquid surface with the oil/fat composition. In the coating step, the oil and fat composition is added to the water-containing liquid in an amount where the amount (g) of the oil and fat composition divided by the area (cm ² ) of the liquid surface is 0.007 or more (g/cm ² ). The heat retention method according to claim 1, comprising the step of adding the water-containing liquid to the amount of the oil and fat composition. The heat retention method according to claim 1, wherein the water-containing liquid has a temperature higher than the contact air temperature. The heat retention method according to claim 1, wherein the water-containing liquid has a temperature difference of 5° C. or more with respect to the contact air temperature. The heat retention method according to claim 1, wherein the oil and fat composition contains the emulsifier A. The heat retention method according to claim 1, wherein the oil and fat composition contains the emulsifier B. The heat retention method according to claim 1, wherein the oil and fat composition contains the emulsifier C. The heat retention method according to claim 8, wherein the emulsifier C is one or more selected from polyglycerin fatty acid ester, organic acid monoglyceride, sorbitan fatty acid ester, and propylene glycol monoester. The heat retention method according to claim 1, wherein the fat or oil is a refined vegetable oil. The oil and fat composition according to any one of claims 1 to 10 for use in the heat retention method according to any one of claims 1 to 10. A method of increasing the ratio of covering the liquid surface of a water-containing liquid (liquid surface occupancy) with an oil and fat composition, the method comprising:
The fat and oil composition contains 40 to 99.9% by mass of fats and oils, and 0.1 to 60% by mass of one or more emulsifiers selected from the following emulsifiers A, B and C: A composition, a method.
Emulsifier A: Sucrose fatty acid ester in which 50% by mass or more of the constituent fatty acids are unsaturated fatty acids Emulsifier B: Polyglycerin condensed ricinoleate ester Emulsifier C: Emulsifier with HLB 3 to 8