JP3882094B2 - How to prevent browning of cooked barley - Google Patents

Description

上記のような前処理した大麦類は、乾物製品として製品化する場合には、前処理した大麦類を凍結乾燥することが望ましい。
【００２５】
また前処理した大麦類をそのまま製品化する場合（容器に充填）には、下記のような加工を加えることが望ましい。
１）米と炊飯して無菌包装する。
２）米と混ぜて加圧加熱殺菌する。
【００２６】
次に、褐変原因物質を減少もしくは除去する処理を大麦類に施す場合について説明する。
Ａ）原料の選別
元来、ポリフェノール含量の少ない原料を選別することが望ましい。そして炊飯しても褐変しない範囲として、全ポリフェノール量が約１０ｍｇｗ／ｗ％以下がよいと考えられる。この全ポリフェノール量は大麦からメタノール水溶液により簡単に抽出される成分をＦｏｌｉｎ−Ｄｅｎｉｓ法により定量した値であって、測定に影響を及ぼすアミノ酸は予め除いておいた場合の量である。
Ｂ）搗精度の基準
搗精度は高いほど好ましい（６５％以上）。なお製品の搗精度について、当社の製品を例にとって記述する。
【００２７】
パリエスペシャル ：４５％、米粒麦（黒条線除去）：５５％、押麦 ：５５〜６０％、なおその際の原料の分類について下記表２に基づいて説明する。
【００２８】
【表２】

Ｃ）煮沸による熱処理
大麦を煮沸（沸騰水中に大麦を入れて加熱）処理し、これを炊飯すると褐変が抑制される。ただし、全ポリフェノール量は１０ｍｇｗ／ｗ％以下が好ましく、全ポリフェノール量の多い大麦の場合には、煮沸中に逆に褐変する。
【００２９】
大麦中の全ポリフェノール量は少ない方が好ましく、約１０ｍｇｗ／ｗ％以下が良好であった。また大麦類をこの量を満足するように搗精した大麦を煮沸することもできる。さらに、大麦類をこの量を満足するように煮沸して得てもよい。
【００３０】
煮沸処理は沸騰水中で５〜１５分が好ましく、５分以内では効果が弱く、１５分以上実施しても大差なくなる。また時間が長いほど大麦の歩留りも悪くなる。煮沸前に対して煮沸後の歩留りは次の通りである。
【００３１】
５分 ： ９０〜９５％、１０分 ： ８５〜９０％、１５分 ： ８０〜８５％、この煮沸による褐変抑制の原理は、加熱中にポリフェノール類が大麦類から溶出して除かれるために褐変が起こりにくくなるものと考えられる。すなわち、沸騰時間と歩留り低下のバランスから５〜１５分の加熱時間が適当である。
Ｄ）酵素処理
大麦類を酵素水溶液に浸漬（加温）することにより、褐変が抑制される。
【００３２】
この方法による褐変の抑制原理は煮沸処理と同じである。すなわち、酵素により大麦類の組織が崩れ、これに伴ってポリフェノール成分が溶出し、除かれることになる。したがって大麦類の歩留りも低下する。上記酵素としてはプロテアーゼ（蛋白質分解酵素）が好ましい。これはポリフェノール成分が蛋白質と親和性が強く、蛋白質組織と結合していることに由来するものと思われる。プロテアーゼの中では植物起源のパパインあるいはブロメラインが好ましい。
【００３３】
なお、上記酵素には−ＳＨ基が存在し、この官能基による褐変の抑制効果が推定される。酵素処理の好ましい条件は次の通りである。
【００３４】
対象：全ポリフェノール量が約１０ｍｇｗ／ｗ％以下の大麦類ただし、酵素処理後にこの量を満足するように処理してもよい。
【００３５】
濃度：０．１〜０．５％（歩留り低下とのバランス）
処理時間：３０〜５０℃で１〜６時間上記のようにして煮沸処理や酵素処理を施した大麦類には大量の水分が吸水されているため、処理後の大麦類を凍結乾燥して用いることが必要である。もし凍結乾燥しない場合には、米とともに炊飯して無菌包装したり、米と混ぜて加圧加熱殺菌する。
Ｅ）搗精方法
図２のように蒸煮工程を施した大麦類の場合、最終製品の搗精度を高められるとともに、黒条線を効率よく取り除くことができ、褐変の抑制される大麦類を得ることができる。このときの蒸煮方法としては、蒸気（約１００℃）を直接大麦に１０〜１５分間吹き付ける条件が良好である。これは、蒸煮により麦粒表面が糊化され、固くなり、表層より均一に削られるため、ポリフェノール成分の多い糊粉層が除かれることに起因する。しかしながら蒸煮工程を施さない大麦類の場合は表層より均一に削られることがなく、黒条線も除かれにくい。さらに蒸煮工程を施した場合には、施さない場合に比べて黒条線の除去率は約２倍に増加する。
【００３６】
【発明の実施の形態】
以下この発明の炊飯した大麦類の褐変防止方法の実施の形態を、実施例に基づいて詳細に説明する。
【００３７】
【実施例１】
（試料１）大麦類としていずれも茨城県産（大粒）米粒麦（株式会社はくばく製 搗精度５５％）を使用し、下記成分を水に混合、溶解させた前処理溶液を大麦に対して２倍量添加し、４０℃、１時間浸漬した。
前処理溶液：β−サイクロデキストリン １．５０％、メチルセルロース ０．０２％、 パパイン ０．５０％、グルタチオン（還元型） ０．１０％
（試料２）前処理溶液として水を使用し、上記大麦を４０℃、１時間浸漬した。
（試料３）前処理を施さなかった。
【００３８】
上記試料を使用して麦ごはんを炊飯し、１２時間、６０℃で保温を行なった。そして各試料を官能試験により評価したものを表３に示す。官能検査でのパネル員の選定は、食味を５年以上経験した熟練者を選んだ。
【００３９】
なお評価方法は１点を対照試料とし、他の２点を対照と比較させて評価させ、完全ランダマイズして実施した。点数は試料３を対照（０）として集計し直し、平均値で表わした。これらを評価した官能検査用紙を表４に示す。
【００４０】
（以下余白）
【００４１】
【表３】

（以下余白）
【００４２】
【表４】

【００４３】
【実施例２】
（試料１）大麦類としていずれもカナダ産（小粒）米粒麦（株式会社はくばく製搗精度５５％）を使用し、沸騰水中で５分間加熱し、冷却を兼ねて水洗した。
（試料２）試料１と同様の処理を施した。ただし加熱は１０分間とした。
（試料３）加熱処理を施さなかった。
【００４４】
上記試料を使用して麦ごはんを炊飯し、１２時間、６０℃で保温を行なった。そして各試料を官能試験により評価したものを表５に示す。
【００４５】
【表５】

【００４６】
【実施例３】
（試料１）大麦類としていずれもカナダ産（小粒）のものを使用し、搗精度を７０％に調製した。続いて蒸煮を１５分間（約１００℃）施し、水分含量が１３％になるまで乾燥させた。これを再搗精し、５５％の搗精度とした。
（試料２）搗精中に蒸煮を施さず、５５％の搗精度としたもの。
（試料３）７０％の搗精度としたもの。
【００４７】
上記試料を使用して麦ごはんを炊飯し、１２時間、６０℃で保温を行なった。そして各試料を官能試験により評価したものを表６に示す。
【００４８】
【表６】

【００４９】
【発明の効果】
この発明の炊飯した大麦類の褐変防止方法によれば、褐変の成分を充分に取り除くことができ、炊飯した場合に褐変するという問題を根本的に解消することが可能であり、しかも大麦類の重要なミネラル成分や食物繊維を除去してしまったり、かつ製品の歩留りが低下してコストが大幅に上昇してしまうという欠点のない麦ごはんを提供することができるようになった。
【図面の簡単な説明】
【図１】この発明の炊飯した大麦類の褐変防止方法で得た大麦類を麦ごはんとして食する過程を示すブロック図である。
【図２】この発明の炊飯した大麦類の褐変防止方法を適用して大麦類を得る工程を示すブロック図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for preventing the browning of barley, wherein “barley rice” is cooked under the same conditions as those for cooking conventional cooked rice, and further the browning of barley is prevented when kept warm.
[0002]
[Prior art]
Traditionally, barley has been recommended to be eaten every day because it is rich in various mineral components and dietary fiber, but it has the disadvantage that it is difficult to cook or easily brown, and is commonly used The current situation is not to say. Moreover, it is often used by adding about 10 to 30% to the cooked rice, but there is a problem that there is resistance to eating because the color when browning is significantly different from the cooked rice. .
[0003]
In order to solve the above-mentioned problems, conventionally, the black line attached to the center of barley that is thought to affect browning is removed by dividing the barley into two at the black line and finening it. To be done.
[0004]
In addition, it is thought that browning has an effect on the barley hull and its inner layer, and in order to remove these reliably, drought components are also removed by greatly increasing the culling accuracy. Yes.
[0005]
[Problems to be solved by the invention]
However, in the case where the black stripes attached to the center of barley are removed by splitting into two at the black stripes and scouring, the influence of the black stripes can be prevented, but other parts Browning could not be prevented, and it was not a sufficient solution.
[0006]
In addition, in order to remove barley husk and its inner layer, the accuracy of culling and removal of browning components, the problem of browning when cooked is not fundamentally solved. However, there are disadvantages that most of the important mineral components of barley are removed, and that the yield of the product is lowered and the cost is significantly increased.
[0007]
Therefore, the present inventors studied how the browning phenomenon of barley occurs and obtained the following conclusion. The main cause of browning is polyphenols, and browning substances are produced by their oxidation and polymerization. There are two types of barley: polyphenol components that are easily extracted with aqueous methanol and polyphenol components that are not easily extracted by binding to proteins and fibers, and browning cannot be suppressed even if the former is removed. I found out. It is also found that the barley is steamed once during milling, and the surface of the wheat grain is gelatinized and then milled again to increase the milling accuracy while evenly shaving from the surface layer and browning is suppressed in cooking rice. It was. That is, in order to fundamentally suppress browning, it is necessary to reduce the polyphenol component that is easy to extract as much as possible and to stop the oxidation / polymerization reaction of the polyphenol component that is difficult to extract.
[0008]
The present invention can remove browning components, suppress oxidation and polymerization reactions, and can fundamentally eliminate the problem of browning when cooked, and is an important mineral in barley It has become possible to provide a method for preventing browning of cooked barley without the disadvantages of removing components and reducing the yield of the product and significantly increasing costs.
[0009]
[Means for Solving the Problems]
In other words, the method for preventing browning of cooked barley according to the present invention is characterized in that the treatment for reducing or removing browning-causing substances is applied to barley.
[0010]
The method for preventing browning of cooked barley according to the present invention is characterized by using barley with a polyphenol content of about 10 mgw / w% or less.
[0011]
The method for preventing browning of cooked barley according to the present invention is characterized in that the polyphenol content is about 10 mgw / w% or less by performing heat treatment such as boiling the barley.
[0012]
The method for preventing browning of cooked barley according to the present invention is characterized in that the polyphenol content is adjusted to about 10 mgw / w% or less by subjecting the barley to a treatment for reducing or removing browning-causing substances by enzyme treatment.
[0013]
The method for preventing browning of cooked barley according to the present invention is characterized by using barley having a koji accuracy of 65% or more.
[0014]
The method for preventing browning of cooked barley according to the present invention is characterized by using barley having a koji accuracy of 65% or more by subjecting the barley to a treatment such as steaming and then scouring.
[0015]
In this invention, it is also possible to combine with impregnation of barley with an oxidation / polymerization inhibitor. As this oxidation / polymerization inhibitor, β- cyclodextrin, methylcellulose, curdlan, gelatin, and glutathione (reduced type) are used. The basic browning is caused by the oxidation of the phenolic hydroxyl group (—OH) of the polyphenol component. Therefore, the reactivity of the —OH group may be suppressed. The preferred concentration (w / w%) of the aqueous solution when this is used as a pretreatment liquid or a rice cooking water solution is as follows.
[0016]
β- cyclodextrin: 1.00-1.50%
Above this, it becomes difficult to dissolve and the suppression effect does not change.
[0017]
It is considered that the reaction stops because the —OH group is encapsulated by the inclusion action which is a characteristic of β- cyclodextrin.
[0018]
Methylcellulose: 0.01-0.05%
More than this, viscosity increase curdlan: 0.20 to 0.50%
Above this, the high molecular weight compounds such as increased viscosity methylcellulose and curdlan are combined with polyphenols through hydrogen bonding, and the reaction of —OH groups stops.
[0019]
Gelatin: 0.05-2.00%
Viscosity increases beyond this Polyphenols bind to hydrophobic regions derived from the aromatic ring of gelatin (protein), and then hydrogen bonds develop to form stronger bonds, which associate and crosslink with each other. The reaction of the —OH group stops.
[0020]
Glutathione (reduced form): 0.05-1.00%
Above this, it will be colored in reverse. Also, below the range, there is no browning suppression effect (weak).
[0021]
This structure is a peptide in the form of glutamic acid-cysteine-glycine. The reaction is stopped when the -SH group derived from cysteine binds and associates with polyphenols.
Next, barley can be prevented from browning through a treatment step as shown in FIG. As pretreatment (immersion) conditions for treating barley with a pretreatment liquid containing an oxidation / polymerization inhibitor, it is desirable to react at room temperature to about 40 ° C. for 1 to 12 hours. Basically, it is assumed that the inhibitor in the pretreatment solution is adsorbed (absorbed) by barley. The same applies to the case of water for cooking rice. In addition, the influence on the browning suppression of the rice cooking by the pre-processing liquid in that case and the water for rice cooking is as Table 1 below.
[0023]
(The following margin)
[0024]
[Table 1]

When the pretreated barley as described above is commercialized as a dry product, it is desirable to freeze-dry the pretreated barley.
[0025]
When pre-treated barley is produced as it is (filled in a container), it is desirable to add the following processing.
1) Cook with rice and aseptically package.
2) Mix with rice and sterilize under heat and pressure.
[0026]
Next, the case where the process which reduces or removes a browning cause substance is performed to barley is demonstrated.
A) Selection of raw materials It is desirable to select raw materials with a low polyphenol content. And as a range which does not brown even if it cooks, it is thought that about 10 mgw / w% or less of the total polyphenol amount is good. This total polyphenol amount is a value obtained by quantifying components easily extracted from barley with an aqueous methanol solution by the Folin-Denis method, and is an amount when amino acids that affect the measurement are removed in advance.
B) The standard wrinkle accuracy of the wrinkle accuracy is higher (65% or more). The accuracy of the product will be described using our product as an example.
[0027]
Palier special: 45%, rice grain wheat (black strips removed): 55%, oats: 55-60%, and the classification of raw materials at that time will be described based on Table 2 below.
[0028]
[Table 2]

C) Heat treatment by boiling The barley is boiled (barley is put in boiling water and heated), and when this is cooked, browning is suppressed. However, the total polyphenol content is preferably 10 mgw / w% or less, and in the case of barley with a large total polyphenol content, it browns during boiling.
[0029]
The amount of total polyphenols in barley is preferably small, and about 10 mgw / w% or less was good. It is also possible to boil barley that has been refined to satisfy this amount. Further, barley may be boiled to satisfy this amount.
[0030]
The boiling treatment is preferably 5 to 15 minutes in boiling water, and the effect is weak within 5 minutes. The longer the time, the worse the barley yield. The yield after boiling is as follows compared to before boiling.
[0031]
5 minutes: 90-95%, 10 minutes: 85-90%, 15 minutes: 80-85%, the principle of browning suppression by boiling is because polyphenols are eluted and removed from barley during heating. Is considered to be difficult to occur. That is, a heating time of 5 to 15 minutes is appropriate from the balance of boiling time and yield reduction.
D) Browning is suppressed by immersing (heating) enzyme-treated barley in an aqueous enzyme solution.
[0032]
The principle of browning suppression by this method is the same as that of boiling treatment. That is, the barley tissue is destroyed by the enzyme, and the polyphenol component is eluted and removed accordingly. Therefore, the yield of barley is also reduced. As the enzyme, a protease (proteolytic enzyme) is preferable. This is probably because the polyphenol component has a strong affinity for proteins and binds to protein tissues. Among proteases, papain or bromelain derived from plants is preferable.
[0033]
In addition, -SH group exists in the said enzyme, The inhibitory effect of the browning by this functional group is estimated. Preferred conditions for the enzyme treatment are as follows.
[0034]
Subject: Barley with a total polyphenol content of about 10 mgw / w% or less However, it may be processed to satisfy this amount after enzyme treatment.
[0035]
Concentration: 0.1 to 0.5% (balance with yield reduction)
Treatment time: 1 to 6 hours at 30 to 50 ° C. Since a large amount of water is absorbed in the barley subjected to boiling treatment and enzyme treatment as described above, the treated barley is lyophilized and used. It is necessary. If not freeze-dried, cook with rice and aseptically wrap, or mix with rice and pasteurize with heat and pressure.
E) Method of milling In the case of barley that has undergone a steaming process as shown in Fig. 2, it is possible to obtain a barley that can improve the kneading accuracy of the final product and can efficiently remove the black stripes and suppress browning. Can do. As a steaming method at this time, the condition of spraying steam (about 100 ° C.) directly onto barley for 10 to 15 minutes is good. This is due to the fact that the surface of the wheat grain is gelatinized and hardened by steaming, and is evenly shaved from the surface layer, so that the paste powder layer having a high polyphenol component is removed. However, in the case of barley that is not subjected to a steaming step, it is not evenly cut from the surface layer, and the black stripes are difficult to remove. Further, when the steaming process is performed, the removal rate of the black stripes increases about twice as compared with the case where the steaming process is not performed.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the method for preventing browning of cooked barley according to the present invention will be described in detail based on examples.
[0037]
[Example 1]
(Sample 1) As a barley, the Ibaraki-grown (large grain) rice grain wheat (hakaku made cocoon accuracy 55%) is used. Double amount was added and immersed for 1 hour at 40 ° C.
Pretreatment solution: β- cyclodextrin 1.50%, methylcellulose 0.02%, papain 0.50%, glutathione (reduced form) 0.10%
(Sample 2) Water was used as a pretreatment solution, and the barley was soaked at 40 ° C. for 1 hour.
(Sample 3) No pretreatment was performed.
[0038]
Using the above sample, rice was cooked and kept at 60 ° C. for 12 hours. Table 3 shows the results of evaluation of each sample by a sensory test. The panel members were selected for the sensory test by skilled workers who had more than 5 years of experience.
[0039]
The evaluation method was performed by using one point as a control sample and comparing the other two points with the control for evaluation and complete randomization. The score was recounted using Sample 3 as a control (0) and expressed as an average value. Table 4 shows sensory test papers for evaluating these.
[0040]
(The following margin)
[0041]
[Table 3]

(The following margin)
[0042]
[Table 4]

[0043]
[Example 2]
(Sample 1) As barley, Canadian (small) rice barley (Hakubaku Seibu Precision Co., Ltd. 55%) was used, heated in boiling water for 5 minutes, and washed with water for cooling.
(Sample 2) The same treatment as that of Sample 1 was performed. However, heating was performed for 10 minutes.
(Sample 3) Heat treatment was not performed.
[0044]
Using the above sample, rice was cooked and kept at 60 ° C. for 12 hours. And what evaluated each sample by the sensory test is shown in Table 5.
[0045]
[Table 5]

[0046]
[Example 3]
(Sample 1) Canadian barley (small grain) was used as the barley, and the koji accuracy was adjusted to 70%. Subsequently, steaming was performed for 15 minutes (about 100 ° C.), and dried until the water content became 13%. This was re-refined to a wrinkle accuracy of 55%.
(Sample 2) No steaming in the semen and 55% accuracy.
(Sample 3) 70% accuracy.
[0047]
Using the above sample, rice was cooked and kept at 60 ° C. for 12 hours. Table 6 shows the results of evaluation of each sample by a sensory test.
[0048]
[Table 6]

[0049]
【The invention's effect】
According to the method for preventing browning of cooked barley according to the present invention, the browning component can be sufficiently removed, and the problem of browning when cooked rice can be fundamentally solved. It has become possible to provide rice without the disadvantages of removing important mineral components and dietary fiber and drastically increasing costs by reducing product yield.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a process of eating barley obtained by the method for preventing browning of cooked barley according to the present invention as barley rice.
FIG. 2 is a block diagram showing a process for obtaining barley by applying the method for preventing browning of cooked barley according to the present invention.

Claims (4)

A method for preventing browning of cooked barley, characterized by using barley that has been subjected to heat treatment by boiling barley and having a polyphenol content of 10 mgw / w% or less. A method for preventing browning of cooked barley, characterized by using barley that has been subjected to a treatment for reducing or removing browning-causing substances by enzyme treatment and having a polyphenol content of 10 mgw / w% or less. The method for preventing browning of cooked barley according to any one of claims 1 and 2, comprising using barley having a koji accuracy of 65% or more. Cooked barley, characterized by using barley with 65% or higher mashing accuracy after scouring the barley after steaming or enzymatic treatment to reduce or remove browning-causing substances To prevent browning.

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