JP2004089075A - Method for producing freeze-dried deep-fried prawn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing freeze-dried deep-fried prawns which are useful as ingredient materials for instant noodles, etc., surely reconstituted with hot water in state of excellent palatability in several minutes, have reduced shrinkage and curve of prawns after heat treatment and freeze drying, have a slight fall of coating and are not broken during transportation. <P>SOLUTION: The freeze-dried deep-fried prawns are produced by subjecting raw material prawns passed through pretreatment processes including a process for removing at least head parts and shells and a tendon cutting process to each process of boiling, cooling and attaching dust, batter and residue of deeply fried Tempura batter (bits of fried Tempura batter) and freeze-drying the prawns. The hydration ratio reconstitution with hot water at 90-100°C is 230-300% to surely reconstitute the freeze-dried deep-fried prawns into a state of excellent palatability with hot water. <P>COPYRIGHT: (C)2004,JPO

Description

【０００８】
【実施例】
以下、実施例により本発明をより具体的に説明するが、本発明はこれらの実施例により何ら限定されるものではない。
【０００９】
実施例１
本発明のＦＤエビ天ぷら（テスト品）を以下の工程により作製した。
原料エビ→洗浄→頭部除去→サイズ及びグレイド選別→皮むき（殻の除去）→洗浄→ポリリン酸ナトリウムの９％水溶液に約５時間浸漬→水切り→筋切り・伸ばし→約９５℃の熱湯中で約３分間ボイル→冷却→澱粉、卵白粉、食塩、米粉よりなるミックスパウダーを用いた打ち粉付け→水で湿らせた卵白粉を用いたバッター付け→エビ表面に揚げ玉を付着させる天花付け→トレー並べ→予備冷凍→ＦＤ（凍結乾燥）→梱包。
上記工程中、予備冷凍工程は、冷凍機を用いて−２５℃で１０時間冷却することにより行った。続いて、予備冷凍したエビを凍結乾燥器に移し、１Ｔｏｒｒの減圧下で、初期温度８０℃から段階的に温度を下げ、最終的に４０℃になるように設定し、合計で２０時間、ＦＤ（凍結乾燥）を行った。
別に、次のように通常の製法で作製したエビ天ぷらをＦＤ加工しコントロール品とした。
原料エビ→洗浄→頭部除去→サイズ及びグレイド選別→皮むき（殻の除去）→洗浄→水切り→筋切り・伸ばし→澱粉、卵白粉、食塩、米粉よりなるミックスパウダーを用いた打ち粉付け→水で湿らせた卵白粉を用いたバッター付け→エビ表面に揚げ玉を付着させる天花付け→油揚げ（１６０℃で３分間）→トレー並べ→予備冷凍→ＦＤ（凍結乾燥）→梱包。
上記テスト品とコントロール品の工程上の相違は、コントロール品ではテスト品におけるポリリン酸ナトリウム水溶液に浸漬する工程及びボイル工程とそれに続く冷却工程を欠いており、テスト品ではコントロール品における油揚げ工程を欠いている点にある。
続いて、上記テスト品とコントロール品について次のようなテストを行った。
★湯戻し加水率テスト
まず、テスト品及びコントロール品の重量（湯戻し前重量）を測定し、次いで両者を９５℃の熱湯に３分間入れて湯戻しした後の重量（湯戻し後重量）を測定した。
そして次の式により「湯戻し加水率（％）」を算出した。この操作を各々５検体について行った。結果を表２、表３に示す。
湯戻し加水率（％）＝〔湯戻し後重量（ｇ）／湯戻し前重量（ｇ）〕×１００
【表２】

【表３】

表２、表３の結果から明らかなように、テスト品はコントロール品に比べて加水率が平均約８０％高く、より柔らかな状態に湯戻しできることが分る。
★湯戻し後の官能評価テスト
テスト品及びコントロール品を９５℃の熱湯に３分間入れて湯戻しし、食感をパネラー５名により３段階で評価した。評価結果を表４に示す。なお、評価基準は次の通りである。
○…硬い部分がなく、良好な食感である。
△…部分的に硬い箇所があるが、概ね良好な食感である。
×…全体的に硬く、食感がよくない。
【表４】

表４の結果から、テスト品の方がコントロール品よりも柔らかく、食感のよい状態に湯戻しできることは明らかである。
なお、テスト品とコントロール品の湯戻し後の差異は、上記テストの結果だけでなく外観上からも歴然としているので、図１として両者のカラー写真のコピーを示すと共に、元のカラー写真を物件提出した。
【００１０】
【発明の効果】
本発明によれば、熱湯により数分間で確実に食感のよい状態に湯戻りし、熱処理後及び凍結乾燥後のエビの縮み・湾曲が少なく、衣落ちも少なく、かつ輸送時に壊れることがない、即席麺などの具材として非常に有用な、凍結乾燥法によるエビ天ぷら及びその製造方法を提供できる。
【図面の簡単な説明】
【図１】実施例１のテスト品及びコントロール品の湯戻し後の写真。
（ａ）テスト品
（ｂ）コントロール品[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an FD (freeze-dried) shrimp tempura that can be used for ingredients of instant noodles and the like, and a method for producing the same.
[0002]
[Prior art]
For example, Japanese Patent Publication No. 8-4463 discloses a method for producing instant noodles and packed noodles mainly made of vegetables by a freeze-drying method, but there is no description about shrimp.
Japanese Patent Laid-Open No. 9-84569 discloses a method for producing frozen shrimp tempura in which headless shrimp is fried in oil and then frozen, but the freeze-drying method is not employed, and this shrimp Tempura is thawing cooked in a microwave oven and is not an invention relating to ingredients for instant noodles.
In addition to the above, Japanese Patent Application Laid-Open No. 6-121645 discloses a method for producing tempura as frozen food, and Japanese Patent Application Laid-Open No. 9-275842 discloses a frozen food containing shrimp containing phosphate and the like, Japanese Patent Application Laid-Open No. 2002-196 describes a frozen tempura and a method for producing the same, but neither describes a freeze-drying.
Ingredients for instant noodles by freeze-drying are known before the filing of this application. As far as the present inventors know, nothing has been put into practical use.
[0003]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems of the prior art, reliably returns hot water in a few minutes with hot water, reduces shrimp shrinkage / curvature after heat treatment and freeze-drying, and reduces clothes loss. Another object of the present invention is to provide a shrimp tempura by freeze-drying and a method for producing the shrimp tempura that are very useful as ingredients such as instant noodles that do not break during transportation.
[0004]
[Means for Solving the Problems]
The above problems are solved by the following inventions 1) to 5).
1) FD shrimp tempura produced by a freeze-drying method and having a "hot water rehydration rate" of 230 to 300% with hot water at 90 to 100 ° C that surely returns to a good texture with hot water.
2) Shrimp raw materials that have undergone at least the pretreatment process including the head and shell removal process and the muscle cutting process are freeze-dried through the steps of boiling, cooling, dusting, battering, and topping (fried balls). The manufacturing method of FD shrimp tempura characterized by the above-mentioned.
3) The method for producing FD shrimp tempura according to 2), wherein, in the pretreatment step of raw material shrimp, it is immersed in a 1 to 10% by weight phosphate aqueous solution and refrigerated for 3 to 6 hours, followed by draining and muscle cutting. .
4) The method for producing FD shrimp tempura according to 3), wherein the phosphate is sodium polyphosphate.
5) The method for producing FD shrimp tempura according to any one of 2) to 4), wherein the FD shrimp tempura is heated to 50 to 80 ° C. during freeze-drying.
[0005]
Hereinafter, the present invention will be described in detail.
The raw shrimp used in the present invention may be raw shrimp or frozen shrimp. However, when using frozen shrimp, it is preferable to thaw slowly over several hours at room temperature or low temperature without thawing suddenly by heating in order to thaw without damaging the shrimp tissue as much as possible.
In general, shrimp pretreatment steps include cleaning of raw shrimp, removal of head / shell / back (if necessary), size / grading, and cutting / stretching. Size / grading is a process to reduce product variation, and muscle cutting / stretching is a process to reduce shrimp shrinkage / curvature after heat treatment and freeze-drying. A known method of extending after inserting sharp blades such as knives in several places may be adopted.
In the present invention, it is desirable to add a treatment step with an aqueous solution of phosphate, carbonate or the like prior to the muscle cutting step in addition to the above-described normal step. This treatment step is performed to improve the return of hot water by hot water, and includes sodium polyphosphate, potassium polyphosphate, sodium pyrophosphate, potassium pyrophosphate, sodium metaphosphate, potassium metaphosphate, sodium bicarbonate, sodium carbonate. The shrimp is immersed in an aqueous solution such as sodium malate and refrigerated for 3 to 6 hours to inflate the shrimp as much as possible, and then drained (dehydrated). Of these, sodium polyphosphate is effective. The concentration of the aqueous solution is 1 to 10% by weight, preferably 7 to 9% by weight.
[0006]
Shrimp pretreated as described above are boiled and then cooled. It is desirable that the boil process is performed by dipping in hot water at around 90 to 95 ° C. for about 1 to 5 minutes, preferably about 1 to 3 minutes.
The adoption of this boil process is a feature of the present invention that is different from the prior art, and the prior art has a process of frying with oil at 160 to 180 ° C. to make tempura, and the flavor, texture, etc. of ingredients However, in the present invention, since the above boil process is employed instead of frying with oil, the processing temperature can be greatly lowered, and the flavor and texture of ingredients are hardly impaired.
Subsequently, dusting, battering, and tempering (fried balls) are performed. Usually, mixed powder consisting of starch, egg white powder, salt and rice flour is used for dusting, and egg white powder is used for battering. And water. These steps may employ known means.
[0007]
Finally, freeze-drying (FD) is performed. Freeze-drying is performed by cooling to about −25 ° C. or less and freezing (this process is usually referred to as pre-freezing), and holding at a temperature of 40 to 80 ° C. for 15 to 25 hours under a reduced pressure of about 1 Torr or less. By sublimating. By such an operation, heat can be applied to the dusting powder or batter powder to make it easy to eat.
A comparison table of materials and processes between the present invention and the technique described in the publication described in the section of the prior art is shown below. In addition, the case where there existed a material and a process was set to "(circle)", and the case where there was no was set to "-".
[Table 1]

[0008]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited at all by these Examples.
[0009]
Example 1
The FD shrimp tempura (test product) of the present invention was produced by the following steps.
Raw material shrimp → Cleaning → Head removal → Size and grade selection → Peeling (shell removal) → Cleaning → Soaking in 9% aqueous solution of sodium polyphosphate for about 5 hours → Draining → Stretching and stretching → In hot water at about 95 ℃ Boil for about 3 minutes → Cooling → Dashing using a mixed powder consisting of starch, egg white powder, salt and rice flour → Battering using egg white powder moistened with water → Attaching fried balls to the shrimp surface → Tray arrangement → preliminary freezing → FD (freeze drying) → packing.
During the above steps, the preliminary freezing step was performed by cooling at −25 ° C. for 10 hours using a refrigerator. Subsequently, the pre-frozen shrimp was transferred to a lyophilizer, and under a reduced pressure of 1 Torr, the temperature was gradually reduced from an initial temperature of 80 ° C., and finally set to 40 ° C., for a total of 20 hours. (Freeze drying) was performed.
Separately, shrimp tempura prepared by a normal manufacturing method as follows was subjected to FD processing to obtain a control product.
Raw material shrimp → Washing → Head removal → Size and grade selection → Peeling (shell removal) → Washing → Draining → Stretching and stretching → Dusting using mixed powder consisting of starch, egg white powder, salt and rice flour → Battering using egg white powder moistened with water → Apricot with fried balls attached to shrimp surface → Deep-fried (3 minutes at 160 ° C) → Tray arrangement → Pre-freezing → FD (Freeze drying) → Packing.
The difference in the process between the test product and the control product is that the control product lacks the sodium polyphosphate aqueous solution process and the boil process followed by the cooling process in the test product, and the test product lacks the frying process in the control product. There is in point.
Subsequently, the following test was performed on the test product and the control product.
★ Hot water rehydration test First, weigh the test product and the control product (weight before reconstitution), and then put both in 95 ° C hot water for 3 minutes to reconstitute the water (weight after reconstitution). It was measured.
And "hot water rehydration rate (%)" was calculated by the following formula. This operation was performed for 5 samples each. The results are shown in Tables 2 and 3.
Water reconstitution rate (%) = [weight after reconstitution (g) / weight before reconstitution (g)] × 100
[Table 2]

[Table 3]

As is apparent from the results of Tables 2 and 3, it can be seen that the test product has an average water content of about 80% higher than that of the control product and can be reheated to a softer state.
★ Sensory evaluation after reconstitution with hot water The test product and the control product were placed in hot water at 95 ° C. for 3 minutes to reconstitute with hot water, and the texture was evaluated by 5 panelists in 3 stages. The evaluation results are shown in Table 4. The evaluation criteria are as follows.
○: There is no hard part and a good texture.
Δ: Although there are some hard portions, the texture is generally good.
X: It is hard overall and the texture is not good.
[Table 4]

From the results of Table 4, it is clear that the test product is softer than the control product and can be reheated to a good texture.
The difference between the test product and the control product after re-heating is obvious not only from the result of the above test but also from the appearance. Therefore, a copy of both color photographs is shown in FIG. submitted.
[0010]
【The invention's effect】
According to the present invention, hot water surely returns to a good texture in a few minutes with hot water, shrimp shrinkage / curvature after heat treatment and lyophilization is small, there is little clothing loss, and it does not break during transportation It is possible to provide shrimp tempura by freeze-drying and a method for producing the same, which are very useful as ingredients such as instant noodles.
[Brief description of the drawings]
FIG. 1 is a photograph of a test product and a control product of Example 1 after reheating.
(A) Test product (b) Control product

Claims (5)

FD shrimp tempura produced by freeze-drying method and having a "hot water rehydration rate" of 230 to 300% with hot water at 90 to 100 ° C, which surely returns to a good texture with hot water. The raw shrimp that has undergone at least the pretreatment process including the head, shell removal process, and the muscle cutting process are freeze-dried through each process of boiling, cooling, dusting, battering, and topping (fried balls). FD shrimp tempura manufacturing method characterized. 3. The method for producing FD shrimp tempura according to claim 2, wherein in the pretreatment step of raw material shrimp, it is immersed in a 1 to 10% by weight phosphate aqueous solution and refrigerated for 3 to 6 hours, followed by draining and muscle cutting. The method for producing FD shrimp tempura according to claim 3, wherein the phosphate is sodium polyphosphate. The method for producing FD shrimp tempura according to any one of claims 2 to 4, wherein the FD shrimp tempura is heated to 50 to 80 ° C during freeze-drying.

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