JPS623752A - Highly oil absorbing porous powder produced from starch or grain flour as raw material - Google Patents

Abstract

PURPOSE:The titled powder, consisting of starch having a high pregelatination degree and specific surface area and pore diameter satisfying specific conditions, capable of readily powdering a liquid or semisolid fat or oil simply by mixing, having high oil absorption ability and suitable for food, cosmetic, etc. CONSTITUTION:Highly oil absorbing porous powder, obtained by heating starch or grain flour containing >=70wt% starch as a raw material, e.g. with water at >=70 deg.C, to pregelatinize the starch, quickly freezing the resultant pregelatinized material, vacuum freeze-drying the frozen material, pulverizing the freeze-dried material and sieving the resultant powder and having >=80% pregelatinization degree of the starch therein, 1-15mum major axis of powder pores and 3-15m<2>/g specific surface area.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a porous powder made from starch or grain flour and having high oil absorption ability.

BACKGROUND ART Liquid or semi-solid oils and fats have been used in large quantities in an extremely wide range of fields such as foods, cosmetics, and pharmaceuticals. However, liquids and semi-solids are difficult to handle, and
As demand for diversified powder products in various product forms has increased, technology for powdering liquid and semi-solid oils and fats has become necessary.

[Conventional technology and problems]

Several techniques have already been developed for powdering liquid or semi-solid fats and oils. For example, methods of encapsulating fats and oils using gelatin, etc., and methods of emulsifying fats and oils with sugars, dextrins, proteins, emulsifiers, etc. and then spray drying are well known.However, these methods are expensive and expensive. In addition to requiring equipment, it is not suitable for powdering small quantities of a wide variety of oils and fats.

On the other hand, a method is known in which oil-absorbing powder is produced by using starch as a main component and gelatinizing, drying, and pulverizing the starch using appropriate equipment and appropriate conditions.

Extruders and drum dryers are typical devices. However, the starch obtained by such a method is flaky and currently only about 2 ml of liquid oil can be absorbed per 1 g of starch. In addition, a method for producing porous starch with almost no gelatinization using a blowing agent is known, and the porous starch has relatively high oil absorption, but
Insufficient gelatinization results in poor texture in foods.
In cosmetics, etc., there are problems such as a lumpy feeling remaining.

In view of the above-mentioned current situation, the present inventors conducted research focusing on the following points.

(1) Liquid or semi-solid fats and oils can be powdered very simply by simply mixing without the need for expensive equipment.

(2) Very high oil absorption capacity (Ig starch absorbs at least 3 ml of liquid oil and is in powder form).

(3) Starch or grain flour containing 70 weight or more of starch is used as a raw material, and the resulting powder is swollen and hydrated with water at room temperature.

By satisfying these conditions (1) to (3), it is possible to easily powderize liquid or semi-solid fats and oils, and to obtain a powder with high oil absorption performance that can be used in foods and cosmetics. It becomes possible.

[Means for solving the problem] As a result of research, the present inventors found that starch or flour containing 70% by weight or more of starch has a degree of gelatinization of starch of 80% or more, and under certain specific conditions. It was discovered that the above-mentioned three-row property is satisfied when the powder is made into a porous powder, leading to the completion of the present invention.

That is, the present invention is characterized in that the degree of gelatinization of starch in the powder is 80% or more, the pore diameter of the powder is 1 to 15 μm, and the specific surface area is 3 to 15 m/g. , relates to a highly oil-absorbing porous powder made from starch or grain flour containing 70% by weight or more of starch.

In the present invention? Porous powder exhibits high oil absorption when its pore diameter, that is, the diameter of the pores, is within the range of 1 to 15 −. Especially 3~10I! It is desirable that 80% or more of the total number of holes be rn. If the pore diameter is less than 1-1, the oil absorption rate will decrease, and if the pore diameter is larger than 15-, the oil-holding power will decrease, and at the same time, the powder property will decrease. However, some of the porous powders may be destroyed during production, resulting in the presence of pores larger than 15p, or pores smaller than 1-1, but this may occur to the extent that the oil absorption capacity is not reduced. Its existence is not a problem if it is in small quantities. In the present invention, the pore diameter was determined by direct observation using a scanning electron microscope.

The specific surface area of the powder is 3 to 15 m/g, preferably 5 to 13 m/g.
m/g, and those having a specific surface area within this range exhibit high oil absorption. If the specific surface area is less than 3ml/g, the oil absorption capacity is 2.
ml/g or less, and conversely, if it is larger than 15 m/g, the pore diameter becomes too small and the oil absorption property decreases. The specific surface area value in the present invention was measured using an Ohr type specific surface area meter using nitrogen gas.

In the present invention, "highly oil-absorbing porous powder" refers to starch or flour containing 70% by weight or more of starch as a raw material, which has been subjected to various processing, dried, and ground, and has an oil-absorbing ability. 3. Refers to items of 17g or more. The "oil absorption capacity" as used in the present invention is a value obtained by the following measurement method.

Measurement method: Oil-absorbing porous powder 1 dried at 105°C for 1 hour
Take g in a 100 ml glass beaker. Next, rapeseed oil is added dropwise to the oil-absorbing porous powder from a buret while stirring and mixing with a glass rod. The oil absorption capacity is defined as the amount (ml) of rapeseed oil dripped at the time when the powder cannot absorb all the oil and the exuded rapeseed oil starts to adhere to the beaker wall. All operations are performed at 20°C.

Ordinary raw starches, pregelatinized starches, and grain flours have an oil absorption capacity of 0.
5 ml/g or less. On the other hand, the highly oil-absorbing porous powder according to the present invention exhibits an oil-absorbing capacity of at least 3 ml/g or more.

The starch used as a raw material in the present invention includes all edible starches, and specific examples include corn starch, corn starch,
Potato starch, sweet potato starch, rice starch, waste starch,
These include sago starch and tapioca starch. Dextrins hydrolyzed with enzymes or acids may also be used, but as the freshness of the hydrolyzed water increases, the oil absorption decreases, so DEI
O or less is desirable.

Also suitable for use are flours containing 70% by weight or more of starch. Examples include wheat flour, barley flour, rice flour, buckwheat flour, corn flour, as well as potato flour and sweet potato flour.

The above starch or flour containing 70% by weight or more of starch is
Each may be used alone or in combination of two or more. In addition, protein, as long as the oil absorption capacity is not reduced.
Edible ingredients other than starch such as sugars and polysaccharides can be used in combination, but
It is necessary to contain at least 70% by weight of starch.

A preferred method for producing highly oil-absorbing porous powder from starch or flour containing 70% by weight or more of starch is as follows.

First, water or warm water is added to starch or flour containing 70 times more starch or more and heated to 70° C. or higher to gelatinize the starch. At this time, the degree of gelatinization of starch must be at least 80%. If it is less than 80%, a sufficient amount of oil absorption cannot be obtained, and when used in foods, etc., a rough texture may remain, which is not preferable. The ratio of water or warm water to starch or flour containing 70 parts by weight or more of starch is preferably 5 to 20 parts by weight of the former and 95 to 80 parts by weight of the latter.

If the amount of water or hot water is too large or too small than this ratio, the oil absorption will decrease.

Next, the starch thus obtained or the gelatinized grain flour containing 70 times or more of starch is rapidly frozen. For freezing, it is desirable to quickly and completely freeze within 10 minutes at a temperature of -30°C or less. In addition, in this freezing process, it is desirable to spread the gelatinized product thinly or to form it into a thin line in order to increase the freezing rate. Freezing methods include: ■ Spraying or immersing in cryogenic gas such as liquid nitrogen or liquid air, ■ Immersing in brine, ■ Contacting with a cooling metal plate, glass plate, etc.
There are methods such as (2) using cooled air, (2) immersion in cooled ethanol, and all of these methods (1) to (4) can be used.

Subsequently, completely frozen starch or gelatinized grain flour containing 70% by weight or more of starch is dried. The drying process must be performed under conditions that do not melt the ice crystals of the frozen gelatinized product. For example, freeze-vacuum drying is a typical method. As another method, a method of dehydrating with ethanol at a temperature of −1° C. or lower is also effective. The freeze-vacuum drying and freeze-ethanol dehydration described above are carried out until the moisture content of starch or flour containing 70% by weight or more of starch becomes 15% by weight or less. After this,
Furthermore, it is also possible to further reduce the water content by performing heat drying, vacuum drying, etc.

The dried product thus obtained is pulverized by a pulverizer and sieved. The particle size of the powder after drying is not particularly limited, but
It is desirable to set it to about 20 to 100 mesosh.

The method for producing the highly oil-absorbing porous powder of the present invention includes:
In addition to the above-mentioned methods, it can also be produced by a spray drying method or an explosion method such as a puffing machine.

The highly oil-absorbing porous powder of the present invention can absorb and retain more fats and oils than conventional powders. The term "fats and oils" as used herein includes all liquid or semi-solid fats and oils. Examples include soybean oil, corn oil, cottonseed oil, rapeseed oil, palm oil, coconut oil, fish oil, beef tallow, lard, and whale oil, as well as hydrogenated products, transesterified products, and fractionated products of these oils and fats. .

In addition, all liquid or semi-solid oil-soluble substances other than fats and oils can be similarly absorbed.

"Oil-soluble substances" include, for example, oil-soluble surfactants, hydrocarbons, and organic solvents. Examples of the oil-soluble surfactant include monounsaturated fatty acid glycerin ester, monosaturated fatty acid glycerin ester having 8 or less carbon atoms, unsaturated fatty acid sorbitan ester, polyoxyethylene unsaturated fatty acid sorbitan ester, and the like. Examples of hydrocarbons include liquid paraffin and limonene, and examples of organic solvents include propylene glycol, ethanol, methanol and the like. It can also be applied to oil-soluble flavors and the like.

〔Example〕

Example 1 90 parts by weight of water was added to 10 parts by weight of corn starch, and a gelatinized starch having a degree of gelatinization of 90% was produced while stirring with heating. Add this to seven tons of dry ice (approximately -70℃)
The mixture was quickly and completely frozen for 10 minutes, and then freeze-dried in a vacuum. Next, the vacuum dried product was pulverized using a pulverizer, and then sieved to obtain a highly oil-absorbing porous powder that passed through 30 meshes.

Example 2 90 parts by weight of water was added to 10 parts by weight of corn starch, and a starch gelatinized product having a degree of gelatinization of 100% was produced while stirring with heating. Add this to dry ice-acetone (approximately -70°C).
) and then vacuum freeze-dried. Next, the vacuum dried product was pulverized using a pulverizer, and then sieved to obtain a highly oil-absorbing porous powder that passed through 30 meshes.

Example 3 98% water was added to 2 parts by weight of thin wheat flour with a starch content of 75%.
Parts by weight were added, and while heating and stirring, a gelatinized wheat flour with a degree of gelatinization of 98% was obtained. This was quickly frozen with liquid nitrogen and then vacuum freeze-dried. Next, crush this using a crusher,
The powder was sieved to obtain a highly oil-absorbing porous powder that passed through 20 meshes.

Example 4 95 parts by weight of water was added to 5 parts by weight of potato starch,
While heating and stirring, a gelatinized potato starch with a degree of gelatinization of 85% was obtained. 100 g of this starch gelatinized product was immersed in 1 kg of ethanol that had been previously cooled to -70° C. with dry ice, and rapidly frozen for 10 minutes. After rapid freezing, the temperature was raised to -5°C, stirred for 1 hour, and dehydrated. The alcohol was then filtered off and the ethanol was completely removed under vacuum. Finally, it was crushed using a crusher and sieved to obtain a highly oil-absorbing porous powder that passed through 20 meshes.

Example 5 95 parts by weight of water was added to 5 parts by weight of potato starch,
Potato starch α with a degree of mono-gelatinization of 100% while heating and stirring
I got a monster. 100 g of this starch gelatinized product was immersed in 1 kg of ethanol that had been previously cooled to -70°C with dry ice, and rapidly frozen for 10 minutes. After rapid freezing, the temperature was raised to -5°C, stirred for 1 hour, and dehydrated. The alcohol was then filtered off and the ethanol was completely removed under vacuum. Finally, it was crushed using a crusher and sieved to obtain a highly oil-absorbing porous powder that passed through 20 meshes.

Comparative Example 1 90 parts by weight of water was added to 10 parts by weight of corn starch, and a gelatinized starch having a degree of gelatinization of 100% was produced while stirring with heating. This was slowly frozen in a -20°C freezer for 30 minutes, and then vacuum freeze-dried, pulverized, and sieved in the same manner as in Example 1 to obtain a powder passing 30 meshes.

Comparative Example 2 90 parts by weight of water was added to 10 parts by weight of corn starch, and a starch gelatinized product having a degree of gelatinization of 30% was produced while stirring with heating. Next, the mixture was rapidly frozen, vacuum freeze-dried, crushed, and sieved in the same manner as in Example 1 to obtain a powder that passed through 30 meshes.

When this powder was observed using an electron microscope, pores were observed only in a portion of the powder surface (10 to 20 pores), and the specific surface area was extremely small.

Comparative Example 3 90 parts by weight of water was added to 10 parts by weight of corn starch, and a gelatinized starch having a degree of gelatinization of 100% was produced while stirring with heating. This was quickly frozen in liquid nitrogen. Next, this was freeze-dried in vacuum, then ground using a grinder and sieved to obtain a powder that passed through 30 meshes.

Comparative Example 4 99% of water was added to 1 part by weight of thin blade wheat flour with a starch content of 75%.
Parts by weight were added, and while heating and stirring, a gelatinized wheat flour with a degree of gelatinization of 98% was obtained. This was quickly frozen in liquid nitrogen and then vacuum freeze-dried. Next, this was pulverized using a pulverizer and sieved to obtain a powder that passed through 20 meshes.

Test Example 1 The oil absorption capacity, degree of gelatinization, pore diameter, specific surface area, and water solubility of the powders produced in Examples 1 to 5 and Comparative Examples 1 to 4 were measured. The measurement results are shown in Table 1. In addition, the following measurement method was used.

<Measurement of oil absorption capacity> 1 g of powder was placed in a 10 On+1 glass beaker, and rapeseed oil was added dropwise using a buret while stirring and mixing. The amount (ml) of rapeseed oil dropped at the time when the separated fats and oils that could not be completely absorbed began to adhere to the beaker wall was defined as the oil absorption capacity.

<Measurement of degree of gelatinization> The glucoamylase method was used.

<Pore size measurement> Using a scanning electron microscope (JEOL JSM-840),
After gold deposition, it was observed and the diameter of the pores was measured.

Specific surface area measurement〉 Using Ohr type specific surface area meter 21000 manufactured by Shimadzu Corporation,
Measured using nitrogen gas.

Water Solubility> 1 g of the powder was added to 100 ml of water, and after stirring, the amount of water-insoluble white particles remaining was determined by visual observation.

Table 1 Note) Takashi 1: ◎; Completely dissolved.

○: Some insoluble matter remains.

×: Almost insoluble.

〔Effect of the invention〕

The highly oil-absorbing porous powder of the present invention has excellent oil-absorbing properties and can be used in foods,
It has the property of being able to absorb large amounts of liquid or semi-solid oils and fats used in pharmaceuticals, cosmetics, etc., as well as hydrocarbons, oil-soluble surfactants, etc.

Therefore, if the product of the present invention is used, oil-soluble liquid or semi-solid substances (oils and fats, etc.), which were conventionally considered inconvenient to handle, can be
It becomes possible to easily powderize it.

Claims (1)

[Claims] 1. The degree of gelatinization of starch in the powder is 80% or more, the pore diameter of the powder is 1 to 15 μm, and the specific surface area is 3 to 15
7 starch or starch, characterized in that m^2/g
A highly oil-absorbing porous powder made from grain flour containing 0% by weight or more.