Patent Description:
Tempura is a food obtained by adhering a batter, which is composed mainly of wheat flour and water, to ingredients such as seafood and vegetables and then deep-frying the ingredients in oil. The outer coating of tempura has a crisp texture, which is achieved by deep-frying in oil, while the ingredient inside the coating has a juicy taste and texture with umami (pleasant savory taste) trapped inside due to steam-like cooking. These features work together to create a nice unique taste and texture. The tempura coating should preferably have a so-called flower bloom-like, voluminous appearance (fluffiness), while it is required to have a crisp and crunchy texture.

A method generally used for making tempura includes flouring ingredients, then entirely covering the ingredients with a batter obtained by mixing wheat flour with water, and then deep-frying the ingredients in oil. Unfortunately, the batter becomes more viscous as the time elapses from the preparation, which results in low workability as well as a poor coating texture after deep-frying in oil. Therefore, in order to make fluffy tempura with a crisp texture, it is required, for example, to cook quickly after the preparation of a batter, to flour ingredients and adhere the ingredients with the batter in a proper amount, not too much or too little, and to further sprinkle an additional batter during deep-frying in the oil bath (in other words, putting an additional batter on the surface of tempura to increase the volume of the coating during deep-frying), which means that sophisticated skills and complicated procedures are necessary.

There have been proposed tempura batter mixes that have good workability or make it possible to prepare tempura having a coating with a good fluffiness and texture. For example, Patent Literature <NUM> discloses a tempura batter mix including: a heat-treated wheat flour having an R/E ratio of <NUM> to <NUM> as determined with Brabender Extensograph; and an emulsifying agent. Patent Literature <NUM> discloses a batter material that includes a heat-moisture-treated wheat flour having a degree of gelatinization of <NUM>% to <NUM>% and having a viscosity of <NUM> Pa·s to <NUM> Pa·s when the heat-moisture-treated wheat flour is added with <NUM>% by mass of water based on the mass of the four. Patent Literature <NUM> discloses that a mix for deep-frying includes a deep-frying batter composition containing a compression-treated starch and that the mix is used in the form of a batter with a viscosity of about <NUM> to about <NUM>,<NUM> mPa·s. Patent Literature <NUM> discloses a tempura batter mix flour containing modified rice flour that is produced by applying at least one of compressive force, impact force, frictional force, and shearing force to rice grains or a rice flour and has a degree of swelling of <NUM> or more and a maximum gelatinization viscosity of <NUM> BU or less as determined by Amylograph. Patent Literature <NUM> also discloses that a batter is prepared to have a viscosity of <NUM> to <NUM>,<NUM> mPa when adding water thereto. Patent Literature <NUM> discloses a deep-frying batter composition including a batter material and a composite including crystalline cellulose and propylene glycol alginate. Patent Literature <NUM> also discloses that the viscosity of the batter used for tempura is adjusted to fall within the range of <NUM> to <NUM>,<NUM> mPa·s.

Further mixes for preparing tempura batter, which comprise soft wheat flour, are known from <CIT> and <CIT>.

Unfortunately, the conventional batter material containing heat-treated wheat flour still remains unsatisfactory for simple preparation of tempura with a good appearance and texture, for example, because when deep-frying in oil without further sprinkling an additional batter, it results in insufficient fluffiness. In addition, the conventional batter material has a low adhesion property to non-floured ingredients and thus has a problem with workability.

The present invention provides a tempura batter mix that has a good adhesion property to ingredients and makes it possible to easily prepare tempura having a coating with a crisp texture and a fluffy voluminous appearance only by deep-frying in oil after dipping in a batter.

Specifically, the present invention provides a tempura batter mix comprising:.

The tempura batter mix of the present invention has a good adhesion property to ingredients. The tempura batter mix of the present invention can well adhere even to non-floured ingredients while the mix does not adhere to the ingredients in an excessive amount, but adheres in a suitable amount. The tempura batter mix of the present invention also makes it possible to form a tempura coating with a crisp texture and a flower bloom-like, voluminous appearance (fluffiness) only by deep-frying in oil after dipping in batter. According to the tempura batter mix of the present invention, it is capable of easily preparing fluffy tempura with a good texture, which would otherwise require sophisticated skills and complicated procedures in the conventional art.

The tempura batter mix of the present invention comprises a heat-moisture-treated soft wheat flour having a degree of gelatinization of <NUM> to <NUM>% and having a viscosity of <NUM> to <NUM> Pa·s when the heat-moisture-treated soft wheat flour is added with <NUM>% by mass of water based on the mass of the flour; and at least one emulsifying agent selected from the group consisting of a polyglycerol fatty acid ester, a sucrose fatty acid ester, lecithin, and an organic acid monoglyceride.

In the tempura batter mix of the present invention, the heat-moisture-treated soft wheat flour has a degree of gelatinization of <NUM>% to <NUM>%, preferably <NUM>% to <NUM>%, more preferably <NUM>% to <NUM>% and has a viscosity of <NUM> to <NUM> Pa·s, preferably <NUM> to <NUM> Pa·s, when the heat-moisture-treated wheat flour is added with <NUM>% by mass of water based on the mass of the flour. If the heat-moisture-treated soft wheat flour has a degree of gelatinization of less than <NUM>% or has a viscosity of less than <NUM> Pa·s when the heat-moisture-treated soft wheat flour is added with <NUM>% by mass of water based on the mass of the flour, the resulting batter may have an insufficient viscosity and a low adhesion property, failing to sufficiently improve the fluffiness or voluminous appearance of the tempura coating after deep-frying in oil. On the other hand, if the heat-moisture-treated soft wheat flour has a degree of gelatinization of more than <NUM>% or has a viscosity of more than <NUM> Pa·s when the heat-moisture-treated soft wheat flour is added with <NUM>% by mass of water based on the mass of the flour, the resulting batter may have a high viscosity and a too high adhesion property, resulting in an insufficient appearance or texture of the tempura coating after deep-frying in oil.

A raw wheat flour for the heat-moisture-treated soft wheat flour used in the present invention is not particularly limited, as long as, after the heat-moisture treatment, the wheat flour has a degree of gelatinization in the above range and achieves a viscosity in the above range.

The heat-moisture-treated soft wheat flour for use in the present invention can be produced by a process including: subjecting a raw wheat flour to a heat-moisture treatment, which includes adding water or water vapor to the flour and heating the flour; then drying the treated flour; and optionally grinding the dried flour. The heating medium is preferably superheated water vapor or saturated water vapor. Specifically, the heat-moisture-treated wheat flour is preferably produced by bringing superheated water vapor or saturated water vapor into direct contact with the raw wheat flour to heat it. As a more specific example, the heat-moisture-treated wheat flour can be produced by a process including: placing the raw wheat flour directly in a closed container heated by heating means such as a jacket; and, while stirring as needed, blowing superheated water vapor or saturated water vapor into the closed container to heat the raw wheat flour. The heating conditions are preferably a temperature of <NUM> to <NUM> for a time of about <NUM> second to about <NUM> minutes. The heating conditions may be appropriately controlled so as to produce a heat-moisture-treated wheat flour with a desired degree of gelatinization. After the heat-moisture treatment, the drying may be performed by shelf drying, hot air drying, fluidized bed drying, or other drying methods. After drying, the grinding may be performed by various means such as roll grinding, and pin mill grinding.

For ease of preparation of the batter, the heat-moisture-treated soft wheat flour for use in the present invention preferably has an average particle size of less than <NUM>, more preferably <NUM> to <NUM>, even more preferably <NUM> to <NUM>. The heat-moisture-treated soft wheat flour with too large a particle size may be difficult to disperse in water in the process of preparing the batter. In the description, the average particle size of the heat-moisture-treated soft wheat flour means the volume average diameter measured by laser diffraction/scattering method using a particle size distribution analyzer. The particle size distribution analyzer may be, for example, Microtrack MT3000II (manufactured by NIKKISO CO. In order to adjust the average particle size of the heat-moisture-treated wheat flour to the above range, the heat-moisture-treated soft wheat flour after heating or grinding may be classified into desired sizes using known means such as a sieve or a classifier.

The content of the heat-moisture-treated soft wheat flour in the tempura batter mix of the present invention is preferably from <NUM> to <NUM>% by mass, more preferably from <NUM> to <NUM>% by mass, based on the total mass of the mix. If the content of the heat-moisture-treated soft wheat flour is less than <NUM>% by mass, the resulting batter may tend to have a low adhesion property to ingredients. On the other hand, if the content of the heat-moisture-treated soft wheat flour is more than <NUM>% by mass, the resulting batter may take a relatively long time to cook thoroughly and may tend to form a coating with a relatively hard texture after deep-frying in oil.

In the tempura batter mix of the present invention, the emulsifying agent is one or a combination of two or more selected from the group consisting of a polyglycerol fatty acid ester, a sucrose fatty acid ester, lecithin, and an organic acid monoglyceride. In this regard, the polyglycerol fatty acid ester is an ester of a fatty acid and polyglycerol, which is a polymer of glycerol. The sucrose fatty acid ester is an ester of a fatty acid and sucrose. Lecithin is a triglyceride with one fatty acid replaced by a phosphoric acid compound. The organic acid monoglyceride is an ester of an organic acid and glycerin. Examples of the organic acid include acetic acid, lactic acid, citric acid, succinic acid, and diacetyltartaric acid, among which citric acid is preferred. The content of the emulsifying agent in the tempura batter mix of the present invention is preferably from <NUM> to <NUM>% by mass, more preferably from <NUM> to <NUM>% by mass, even more preferably from <NUM> to <NUM>% by mass, based on the total mass of the mix. If the content of the emulsifying agent is less than <NUM>% by mass, the resulting tempura coating after deep-frying in oil may tend to be less fluffy or to have a hard texture. On the other hand, if the content of the emulsifying agent is more than <NUM>% by mass, the resulting batter may tend to have a low adhesion property to ingredients.

In addition to the heat-moisture-treated soft wheat flour and the emulsifying agent, an oil/fat-treated starch is added to the tempura batter mix of the present invention so that the resulting tempura coating can have a further improved adhesion property and fluffiness. The oil/fat-treated starch refers to a starch with a small amount of oil and/or fat adhering to the surface thereof. The oil/fat-treated starch for use in the present invention is preferably prepared by mixing <NUM> parts by mass of starch and <NUM> to <NUM> parts by mass of oil and/or fat homogenously and then drying the mixture. If necessary, the mixture may be heat-treated before or after drying.

The type of starch as a raw material for the oil/fat-treated starch is not particularly limited, examples of which include unmodified starches such as corn starch, waxy corn starch, tapioca starch, potato starch, wheat starch, and rice starch, and modified starches such as gelatinization products, etherification products, esterification products, crosslinking products, and oxidation products of these starches. Any one of these starches may be used alone or two or more in combination. The type of oil and/or fat to be mixed with the raw starch is not particularly limited as long as it is an edible type, examples of which include soybean oil, rapeseed oil, cottonseed oil, safflower oil, sunflower oil, rice oil, corn oil, palm oil, perilla oil, beef tallow, and lard. Any one of these may be used alone or two or more in combination. An oil-rich grain flour, such as non-defatted soy flour, may also be used as a partial or entire alternative to the edible oil and/or fat.

The content of the oil/fat-treated starch in the tempura batter mix of the present invention is <NUM> to <NUM>% by mass, preferably from <NUM> to <NUM>% by mass, based on the total mass of the mix. If the content of the oil/fat-treated starch is more than <NUM>% by mass, the effect of improving the fluffiness or texture of tempura coating may tend to decrease.

In addition to the materials described above, the tempura batter mix of the present invention may contain a grain flour and/or starch. The grain flour is preferably wheat flour (non-heat-moisture-treated wheat flour). Examples of the wheat flour include soft flour, moderate flour, semi-hard flour, hard flour, and durum wheat flour, among which soft flour is preferred. Examples of the grain flour other than wheat flour include whole wheat flour, barley flour, rye flour, rice flour, sorghum flour, and corn flour. Any one of these flours may be used alone or two or more in combination. Examples of the starch include unmodified starches and modified starches (non-oil/fat-treated starches) listed above as raw materials for the oil/fat-treated starch. The tempura batter mix of the present invention may contain one or a combination of two or more of the above grain flours and starches. The content of the grain flour and/or the starch in the tempura batter mix of the present invention may be from <NUM> to <NUM>% by mass, preferably from <NUM> to <NUM>% by mass, based on the total mass of the mix.

If necessary, the tempura batter mix of the present invention may further contain other materials commonly used in tempura batter mixes, such as materials selected from, for example, baking powders; egg powders such as egg white powders and whole egg powders; proteins; thickening agents such as thickening polysaccharides; seasonings such as salt, soy sauce powders, fermented seasonings, saccharides and amino acids; spices; flavors; nutrients such as vitamins; colorants; and powdered oils and fats. The type and amount of these other materials may be adjusted as appropriate depending on the desired properties of tempura and other factors.

The tempura batter mix of the present invention can be produced by mixing the heat-moisture-treated soft wheat flour, the emulsifying agent, the grain flour and/or the starch, and the oil/fat-treated starch and other materials. The tempura batter mix of the present invention may be, but not limited to, in the form of a powder or granules.

A process of making tempura using the tempura batter mix of the present invention may include previously preparing a batter containing the batter mix of the present invention, adhering the batter to an ingredient, and then deep-frying the ingredient in oil. The batter for use in making tempura can be prepared, for example, by adding <NUM> to <NUM> parts by mass, preferably <NUM> to <NUM> parts by mass, more preferably <NUM> to <NUM> parts by mass of a liquid such as water to <NUM> parts by mass of the batter mix of the present invention, and mixing them. It should be noted that the amount of the liquid such as water may be adjusted depending on the type of ingredients for tempura. In this process, the viscosity of the batter is preferably adjusted to <NUM> to <NUM> Pa·s, more preferably <NUM> to <NUM> Pa·s. The batter with a viscosity in the range can have an improved adhesion property to ingredients and can form a fluffier tempura coating. In the description, the viscosity of the batter refers to a value obtained by measuring the viscosity of the batter having a temperature of <NUM> to <NUM> using a B-type viscometer.

Examples of the ingredient include, but are not limited to, seafood such as prawn and shrimp, squid, and sea-gudgeon, meat such as chicken, pork, and beef, and vegetables such as potatoes, eggplants, pumpkins, carrots, onions, and mushrooms, among which seafood and vegetables are preferred. The ingredient may be floured before the batter is adhered to the ingredient, although it is not essential.

The process of adhering the batter to the surface of the ingredient may include dipping the ingredient in the batter or applying or spraying the batter on the ingredient. According to conventional methods, the ingredient adhered with the batter may then be deep-fried in oil at <NUM> to <NUM> for about <NUM> to about <NUM> minutes to make tempura.

The tempura prepared using the tempura batter mix of the present invention is of high quality, having a coating with a crisp texture and a fluffy appearance, even without flouring the ingredient in advance or without further sprinkling an additional batter during deep-frying in oil.

In the description, the degree of gelatinization of the heat-moisture-treated wheat flour, the viscosity with respect to the heat-moisture-treated wheat flour, and the viscosity of a batter are values determined as described below.

The degree of gelatinization (also called the degree of pregelatinization) is measured by β-amylase-pullulanase method or β-amylase-amyloglucosidase method, which is conventional in the art. Hereinafter, the procedure of β-amylase-amyloglucosidase method will be described.

The following formula is used to calculate the degree of gelatinization.

For the measurement of the viscosity with respect to a heat-moisture-treated wheat flour when adding thereto <NUM>% by mass of water based on the mass of the flour, <NUM> of a heat-moisture-treated wheat flour and <NUM> of cold water at about <NUM> are prepared.

For the measurement of the viscosity of a batter, the tempura batter mix of the present invention and cold water are prepared (<NUM> to <NUM> parts by mass of cold water at about <NUM> relative to <NUM> parts by mass of the mix).

The cold water is poured into a bowl (manufactured by Hobart), and the flour is added onto the cold water. The flour and the water are mixed thoroughly by appropriately stirring with a wire whip (manufactured by Hobart). Subsequently, they are stirred firstly for <NUM> seconds and secondly for <NUM> seconds with a mixer (manufactured by Hobart).

Ten minutes after stirring with the mixer, the viscosity of the resulting mixture is measured using a BM-type viscometer.

Hereinafter, the present invention will be more specifically described with reference to examples. It will be understood that the examples are not intended to limit the present invention.

Soft wheat flour (Flour, manufactured by Nisshin Flour Milling Inc. ) was introduced into a closed high-speed mixing machine with its temperature maintained by using a jacket and saturated water vapor was introduced at different temperatures for different blowing periods of time into the mixing machine to carry out heat-moisture treatment, to thereby obtain heat-moisture-treated wheat flours of Reference Examples <NUM> to <NUM>. Table <NUM> shows the degree of gelatinization of each heat-moisture-treated soft wheat flour and the viscosity thereof when adding thereto <NUM>% by mass of water based on the mass of the flour. Each heat-moisture-treated soft wheat flour had an average particle size in the range of <NUM> to <NUM>.

Tempura batter mixes of REFERENCE Preparation Examples <NUM> to <NUM> were each prepared by mixing the materials shown in Table <NUM>.

A batter was prepared by mixing <NUM> of each of the tempura batter mixes of Preparation Examples <NUM> to <NUM> with <NUM> cc of water. Deshelled prawn with tail (<NUM> per prawn) were dipped in each batter to be adhered well. The batter-adhered prawns were deep-fried for <NUM> minutes in salad oil heated at <NUM>. The obtained tempura pieces were taken out of the oil bath, drained oil off, and then allowed to stand at room temperature (about <NUM>) for <NUM> minutes. Subsequently, the quality of the tempura pieces was evaluated by <NUM> panelists based on the evaluation criteria shown in Table <NUM>, and then the scores were averaged. Table <NUM> shows the results.

Tempura batter mixes of Preparation Examples <NUM> to <NUM> were each prepared by mixing the raw materials shown in Table <NUM>.

As in Test Example <NUM>, prawn tempura pieces were prepared using each of the tempura batter mixes of Preparation Examples <NUM> to <NUM>. The quality of the prepared tempura pieces was evaluated as in Test Example <NUM>. Table <NUM> shows the results. Note that Table <NUM> shows again the results of Preparation Example <NUM>.

Tempura batter mixes of Preparation Examples <NUM> to <NUM> were each prepared by mixing the raw materials shown in Table <NUM>. The oil/fat-treated starch used in these preparation examples was produced by adding <NUM> parts by mass of salad oil to <NUM> parts by mass of phosphate-crosslinked tapioca starch (manufactured by Matsutani Chemical Industry Co. ), mixing them uniformly, and then drying the mixture.

Claim 1:
A tempura batter mix comprising:
<NUM> to <NUM>% by mass of a heat-moisture-treated soft wheat flour having a degree of gelatinization of <NUM> to <NUM>% and having a viscosity of <NUM> to <NUM> Pa·s when the heat-moisture treated wheat flour is added with <NUM>% by mass of water at <NUM> based on the mass of the flour;
<NUM> to <NUM>% by mass of at least one emulsifying agent selected from the group consisting of a polyglycerol fatty acid ester, a sucrose fatty acid ester, lecithin, and an organic acid monoglyceride, and. further comprising <NUM> to <NUM>% by mass of an oil/fat-treated starch.