【発明の詳細な説明】[Detailed description of the invention]
この発明はレトルト食品の製造法に関する。
古来より食品の保存には多くの努力が積み重ね
られて来ているが、例えばAF2問題が記憶に新し
いように、今日尚少くない問題が残されている。
食品を容器内に密封し、この包装体が確実に保
存されるための条件で、100℃を越える高い温度
で一定時間加熱する、いわゆるレトルト殺菌は、
低温殺菌（パスツーリゼーシヨン）に比べて、優
れた方法である、と一般に認識されている。すな
わち、レトルト殺菌は低温殺菌に比べて、耐熱性
菌（ボツリヌス菌）に対する安全性が高いだけで
なく、殺菌時間は著しく短かくて済み、且つ、一
般に食品成分の加熱による劣化が少ない特性があ
る為である。
しかしながら、レトルト加熱をして食品の劣化
がおこりにくい、というのはすべての食品に対し
ていえることではない。例えば、レトルト加熱を
経た従来の大豆蛋白のゲルは、100℃以下で加熱
した場合に比べて、ゲル強度が著しく低下し、ゲ
ルが脆くなる欠点があつた。また100℃以下の加
熱であつても、塩分をも含む場合の得られる大豆
蛋白ゲルは、塩の種類や使用量によつて、かなり
ゲル強度が低下する欠点もある。大豆蛋白のもつ
このような欠点は、とりもなおさず、大豆蛋白を
主体とするゲル状食品或は大豆蛋白を結着剤とし
て使用する食品の保存性や、添加物調味料の制約
に及び、商品価値を高める為の障害となる。
本発明者は、しかしながら、特殊な分離手段に
よつて得た大豆蛋白は、レトルト加熱に耐性のあ
るゲルが得られること、しかも含塩状態のゲル状
レトルト食品にすると、低温加熱によつて得た含
塩状態のゲル状食品にした場合よりむしろ優れて
いることを見出した。
該分離手段とは、大豆または脱脂大豆をPH6.0
〜7.0の水性溶媒で抽出する第１段の分画、第１
段の分画で得た可溶性画分をPH5.0〜5.6に移行さ
せる第２段の分画、及び第２段の分画で得た可溶
性画分をPH4.0〜4.8に移行させる第３段の分画と
からなるもの（特願昭54−60899）で、この発明
は該第３段における不溶性画分の中和固形物を含
水状態で含む食品を、Fo値が４以上の条件下に
レトルト加熱することを骨子とする蛋白レトルト
食品の製造法である。
以下の説明では、第ｘ段における可溶性画分と
不溶性画分を、各々Sx成分、Px成分と略記する
こととする。
第１段分画は、大豆または脱脂大豆をPH6.0〜
7.0の水性溶媒で抽出することにより行なう。こ
の分画は、一般の分離大豆蛋白の製造において使
用する水性溶媒のPHが通常微アルカリ性であるこ
とを除けば、通常行なわれている方法でよい。分
画PHが７を越えて高くなると、P3成分のレトルト
耐性が著しく低下する。好ましくはPH6.5以下で
ある。一方分画PHが６に満たないと、次段で得る
P2成分の収量が低下し、著しくは第１段分画と第
２段分画のPH域が重複してしまうので、第１段の
分画を省いたと同様の結果となる。第１段の分画
が行なわれないで、この発明の第２段の分画がい
きなり行なわれると、この発明で副生するP1成分
とP2成分の分離が困難となり、付加価値が高くな
らない。すなわち、この発明で副生するP1成分
は、特に中和する操作を必要とすることなく、近
年食品素材として多くの用途が開発されてきた大
豆多糖類含有物として利用でき、またこの発明で
副生するP2成分は、従来の通常の製法（抽出、PH
４〜５付近での沈澱）によつて得る分離大豆蛋白
と同様の性質を持つている、のであるが、この発
明の第１段の分画を省略したのでは、P1成分とP2
成分が分離しないで不溶性画分となり、これから
P2成分を分取しようとしてPHを再び上昇させても
粘度が上昇して作業が著しく困難となるからであ
る。なお第１段の分画において一般の分離大豆蛋
白の製造と同様、亜硫酸ソーダ、亜硫酸水素ナト
リウム等の還元剤を加えたり、数次の洗浄を行つ
て抽出効率を上げることを行つてもよい。
第２段の分画はS1成分に酸を加えPH5.0〜5.6に
移行させて行なう。この段の該PH域においてはP2
成分の沈降性が弱いので、他段におけるよりも分
離効果をより強力にするような分画操作とするの
がよい。この段における領域よりもPH値が高くな
ると、P3成分のレトルト耐性が低下する。また該
領域よりもPH値が低くなると、第３段のPH域に近
接し、P3成分の収量が低下する。該領域の中で
も、最も好ましいPH域は5.3〜5.5である。
第３段の分画は、S2成分に酸を加えPHを4.0〜
4.8に移行させて行なう。この段のPH域の外では
P3成分の収量が低い。
このようにして得たP3成分は、略中和し、この
固形物含水状態で含む食品をFo値が４以上の条
件下にレトルト加熱して蛋白レトルト食品を得
る。
P3成分は、中和または加熱ゲル化させる前に、
乾燥又は凍結等の保存手段を講じることができ
る。P3成分は、従来得られていた分離大豆蛋白に
比べて塩可溶性が高い性質があるが、加熱ゲル化
する前に加熱処理をすると、その加熱の程度にも
よるが、塩可溶性の性質が低下することがあるの
で、保存手段は加熱を伴わないものがより好まし
い。
P3成分の中和固形物を含む食品は該中和固形物
単独でもよいのはもちろんであるが、適宜、卵蛋
白、魚肉蛋白、畜肉蛋白、グルテン等の少量の蛋
白、小麦粉、でんぷん等の澱粉性物質、油脂、調
味料、香辛料、着色料等を混じて均質化したもの
の他、組織状蛋白繊維状蛋白、魚肉、畜肉等と混
じた食品であつてもよい。
F0値とは、一定濃度の芽胞を殺滅するのに必
要な一定温度の加熱時間を表わし、250〓（121
℃）における致死時間を分であらわしたもので、
他の温度であつても250〓に換算して表わされ
る。F04は一般にボツリヌス菌芽胞の最大熱抵抗
値で換算され121℃４分に対応する例をあげると
105℃100分、110℃32分、115℃10分、125℃12
分、130℃30秒程度であるが、同じ装置で110℃32
分と115℃10分加熱する場合は後者の方が時間
的・エネルギー的に実用的であり、約115℃以上
の温度が採用されるのが一般である。
レトルト容器としては、缶、耐熱性フイルム等
が挙げられ、密封した状態で加熱する。
かくして、保存性が良好で、且つ、良好なゲル
強度の製品を得ることができる。
以下この発明を実施例で説明する。
実施例 １
低変性脱脂大豆10Kgに対して、11倍量の水を加
え、40℃で30分間の抽出（PH6.5）を行ない、P1
成分を分離した後、豆乳（S1成分）に塩酸溶液を
加えてPH5.5に調整して遠心分離（1000G、10
分）し、P2成分を系外に除いて、S2成分にさらに
塩酸溶液を加えてPH4.5に調整し、遠心分離
（100G、10分）によつてP3成分を得た、P3成分
は、水酸化ナトリウム溶液を加えてPH7.0に中和
し、噴霧乾燥した。
噴霧乾燥した粉状物は、次にその１重量部に対
し、食塩を溶解した又は加えていない水４重量部
を加えて均質化し、耐熱性のあるフイルムケーシ
ング（折巾3.5cm）中に充填し、これを120℃
F04.5の加熱を行つたところ、ゲル状蛋白食品が
得られた。
比較として、PH8.0及びPH4.5の二段のPH分画と
し中和後加熱処理する他は、同様に粉状物を得、
その粉状物から、加熱条件を90℃40分又は120℃
F04.5とする他は、同様にゲル状蛋白食品を得
た。
各ゲル状蛋白食品について、岡田式ゼリー強度
計（プランジヤーφ0.5cm）によるゼリー強度測
定（４検体平均値）の結果を下表に示す。
This invention relates to a method for producing retort food. Many efforts have been made to preserve food since ancient times, but many problems still remain today, such as the AF 2 problem, which is still fresh in our minds. Retort sterilization involves sealing food in a container and heating it at a high temperature of over 100℃ for a certain period of time under conditions to ensure that the package is preserved.
It is generally recognized as a superior method compared to pasteurization. In other words, compared to pasteurization, retort sterilization is not only safer against heat-resistant bacteria (Clostridium botulinum), but the sterilization time is significantly shorter, and food ingredients are generally less susceptible to deterioration due to heating. It is for this purpose. However, it cannot be said that all foods are less susceptible to deterioration when heated in a retort. For example, conventional soybean protein gels that have been heated in a retort have the disadvantage that the gel strength is significantly lower and the gel becomes brittle compared to when heated at 100°C or lower. Furthermore, even when heated at 100°C or lower, the resulting soybean protein gel that also contains salt has the disadvantage that the gel strength is considerably reduced depending on the type and amount of salt used. These drawbacks of soybean protein affect the preservability of gel-like foods based on soybean protein or foods that use soybean protein as a binder, and limit the use of additives and seasonings. This becomes an obstacle to increasing product value. However, the present inventor found that soybean protein obtained by special separation means can be used to obtain a gel that is resistant to retort heating, and that when it is made into a salt-containing gel-like retort food, it can be obtained by low-temperature heating. It was found that this product is actually better than a gel-like food containing salt. The separation means means to separate soybeans or defatted soybeans at a pH of 6.0.
1st stage fractionation, extracted with an aqueous solvent of ~7.0
A second stage fractionation in which the soluble fraction obtained in the second stage fractionation is shifted to a pH of 5.0 to 5.6, and a third stage in which the soluble fraction obtained in the second stage fractionation is shifted to a pH of 4.0 to 4.8. This invention consists of a step of fractionation (Japanese Patent Application No. 54-60899), and the present invention is directed to a food containing the neutralized solids of the insoluble fraction in the third step in a hydrated state under conditions where the Fo value is 4 or more. This is a method for producing retort protein foods that consists of heating in a retort. In the following explanation, the soluble fraction and insoluble fraction in the xth stage will be abbreviated as Sx component and Px component, respectively. The first stage fractionation uses soybeans or defatted soybeans from pH6.0 to
This is done by extraction with a 7.0 aqueous solvent. This fractionation may be carried out by any conventional method, except that the pH of the aqueous solvent used in general production of isolated soybean protein is usually slightly alkaline. When the fractional PH becomes higher than 7, the retort resistance of the P3 component decreases significantly. Preferably the pH is 6.5 or less. On the other hand, if the fractional pH is less than 6, it will be obtained in the next step.
The yield of the P2 component decreases, and the PH ranges of the first-stage fraction and second-stage fraction overlap significantly, resulting in the same results as if the first-stage fraction were omitted. If the second stage fractionation of this invention is suddenly performed without performing the first stage fractionation, it will be difficult to separate the P 1 component and P 2 component produced by this invention, and the added value will be high. It won't happen. In other words, the P1 component produced as a by-product in this invention can be used as a soybean polysaccharide-containing substance, which has been developed for many uses as a food material in recent years, without requiring any particular neutralization operation. The P2 component produced as a by-product is produced using conventional manufacturing methods (extraction, PH
However, if the first step of this invention is omitted, the P1 component and P2
The components do not separate and become an insoluble fraction, and from now on
This is because even if the pH is increased again in an attempt to separate the P2 component, the viscosity will increase, making the work extremely difficult. In addition, in the first stage fractionation, as in the production of general isolated soybean protein, a reducing agent such as sodium sulfite or sodium bisulfite may be added, or several washings may be performed to increase the extraction efficiency. The second stage of fractionation is carried out by adding acid to the S1 component and shifting the pH to 5.0 to 5.6. In the PH range of this stage, P 2
Since the sedimentation properties of the components are weak, it is preferable to perform a fractionation operation that makes the separation effect stronger than in other stages. When the PH value becomes higher than the region in this stage, the retort resistance of the P3 component decreases. Furthermore, when the PH value is lower than this range, it approaches the third stage PH range, and the yield of the P3 component decreases. Among these ranges, the most preferred PH range is 5.3 to 5.5. In the third stage of fractionation, acid is added to the S2 component to adjust the pH to 4.0~
I will move it to 4.8. Outside this PH range
The yield of P3 component is low. The P3 component thus obtained is substantially neutralized, and the food containing this solid water-containing state is heated in a retort under conditions where the Fo value is 4 or more to obtain a protein retort food. Before neutralization or heat gelling, the P3 component is
Preservation measures such as drying or freezing can be taken. Component P3 has a property of being highly salt-soluble compared to conventionally obtained isolated soybean protein, but if it is heat-treated before heat-gelling, its salt-solubility properties may be reduced, depending on the degree of heating. Therefore, it is more preferable to use a preservation method that does not involve heating. It goes without saying that foods containing neutralized solids of the three components P3 may contain the neutralized solids alone, but they may also contain a small amount of protein such as egg protein, fish protein, livestock protein, gluten, wheat flour, starch, etc. In addition to homogenized foods mixed with starchy substances, fats and oils, seasonings, spices, colorants, etc., the food may also be foods mixed with textured protein, fibrous protein, fish meat, livestock meat, etc. The F 0 value represents the heating time required at a certain temperature to kill a certain concentration of spores, and is 250〓 (121
It is expressed in minutes as the lethal time at
Even at other temperatures, it is expressed in terms of 250〓. F 0 4 is generally calculated as the maximum thermal resistance value of Clostridium botulinum spores and corresponds to 121℃ for 4 minutes.
105℃ 100 minutes, 110℃ 32 minutes, 115℃ 10 minutes, 125℃ 12
minutes, 130℃ for 30 seconds, but with the same equipment it is heated to 110℃32
When heating at 115°C for 10 minutes, the latter is more practical in terms of time and energy, and a temperature of approximately 115°C or higher is generally used. Examples of retort containers include cans, heat-resistant films, and the like, which are heated in a sealed state. In this way, a product with good storage stability and good gel strength can be obtained. This invention will be explained below with reference to Examples. Example 1 11 times the amount of water was added to 10 kg of low-denatured defatted soybeans, and extraction was performed at 40°C for 30 minutes ( PH6.5 ).
After separating the components, add hydrochloric acid solution to soy milk (S 1 component) to adjust the pH to 5.5 and centrifuge (1000G, 10
The P2 component was removed from the system, the pH was adjusted to 4.5 by adding hydrochloric acid solution to the S2 component, and the P3 component was obtained by centrifugation (100G, 10 minutes). The three components were neutralized to pH 7.0 by adding sodium hydroxide solution and spray-dried. Next, the spray-dried powder was homogenized by adding 4 parts by weight of water with or without salt to 1 part by weight, and filled into a heat-resistant film casing (width 3.5 cm). and heat this to 120℃
When heated at F 0 4.5, a gel-like protein food was obtained. For comparison, a powder was obtained in the same manner, except that it was subjected to two-step PH fractionation of PH8.0 and PH4.5, and was heat-treated after neutralization.
From the powder, the heating conditions are changed to 90℃ for 40 minutes or 120℃.
A gel protein food was obtained in the same manner except that F 0 was 4.5. The results of jelly strength measurement (average value of 4 samples) using an Okada jelly strength meter (plunger φ0.5 cm) for each gel protein food are shown in the table below.
【表】
＊ 全配合物に対する食塩の重量％
測定結果が示すように、対照粉状物を用いた製
品は、塩無添加の状態で、高温加熱によつてゲル
強度が劣化するが、本例製品のゲル強度は良好で
あり、加塩状態においても良好であつた。
実施例 ２
実施例１において食塩にかえて塩化カルシウム
を用いた結果を下表に示す。[Table] * Weight % of salt in total formulation
As the measurement results show, the gel strength of the product using the control powder deteriorates when heated at high temperature without salt, but the gel strength of the product of this example is good, and it does not deteriorate in the salted state. It was also good. Example 2 The results of using calcium chloride instead of common salt in Example 1 are shown in the table below.
【表】
実施例 ３
実施例１で得たP3成分は、同様に中和し、水分
約75％に調節し、２週間の凍結保存後、その360
ｇに、水50ｇ、大豆精製油65ｇ、馬でん25ｇ、玉
ねぎ５ｇ、食塩５ｇ、砂糖５ｇ、その他調味料、
香辛料及び色素計５ｇを加え、家庭用ジユーサー
内で均一なペースト状になるまで混合した。この
ペーストを折り巾3.5cmのケーシングに充填後120
℃15分の加熱をして大豆ソーセージを得た。
比較として、PH8.0及びPH4.5の２段のPH分画を
経た不溶性区分を中和、加熱処理したものを使用
する他は、同様に大豆ソーセージを得た。
両製品は５mm厚の輪切りにし、５名のパネラー
による官能テストに供したところ、全員が本発明
を良しとし、プロフイールとしては本例製品は比
較製品より歯ごたえがこしこしとして肉様食感に
優れている。とのことであつた。
岡田式ゼリー強度計によるゼリー強度は、本例
製品が911ｇ．cm、対照製品が733ｇ．cmであつ
た。[Table] Example 3 The P3 component obtained in Example 1 was similarly neutralized and adjusted to a moisture content of approximately 75%, and after two weeks of frozen storage, its 360%
g, 50g water, 65g refined soybean oil, 25g horse den, 5g onion, 5g salt, 5g sugar, other seasonings,
A total of 5 g of spices and pigments were added and mixed in a household juicer until a uniform paste was formed. After filling this paste into a casing with a folding width of 3.5 cm,
A soybean sausage was obtained by heating for 15 minutes at ℃. For comparison, soybean sausage was obtained in the same manner, except that the insoluble fraction that had undergone two stages of PH fractionation at PH 8.0 and PH 4.5 was neutralized and heat-treated. Both products were cut into 5mm-thick rounds and subjected to a sensory test by five panelists, and all of them agreed that the present invention was good.As for the profile, the product of this example had a better chewiness and meat-like texture than the comparative product. ing. That's what I was told. The jelly strength measured by the Okada jelly strength meter was 911g for this example product. cm, and the control product was 733 g. It was cm.