【発明の詳細な説明】[Detailed description of the invention]
〔産業上の利用分野〕
本発明は、抽出液の持つ特有の風味を損なうことなく濃
縮エキスを得る製造法に関する。
〔従来の技術〕
これまでの：ａ縮エキスは抽出液の持つ風味が弱いため
、本物指向の市場では、濃縮を行わない低濃度の冷凍エ
キスやレトルトエキスが伸びている。
しかしながら、これらの低濃度エキスは、流通コストが
高く加工し難いことから、風味の強い濃縮エキスが求め
られている。
濃縮エキスの風味については、従来エキスの抽出が熱水
抽出で行われているためか濃縮時の温度条件には、関心
が薄く濃縮時の品質劣化は、専らフレーバー成分の揮散
によるものと考えられていた。このため、フレーバーの
揮散という視点での技術開発が散見される。具体的には
、
■ 畜肉エキス系の留出液が、塩基性である場合、被濃
縮液のｐＨを酸性にし、フレーバー揮散を抑制する。
■ 留出液を精留濃縮または、膜濃縮し、濃縮液に加え
る。（フレーバーカフドパツク法）■ 野菜エキスなど
を中心に逆浸透膜を利用した濃縮。
以上のような例があるが、フレーバー成分の挙動に注目
した濃縮がほとんどである。濃縮条件は減圧濃縮が採用
されているが、大体１００〜１３０℃の加熱温度で蒸発
温度はできるだけ低（という蒸発能力が中心となった方
法であり、加熱温度と品質という視点での検討は皆無で
ある。
〔発明が解決しようとする課題〕
このような従来技術における問題点としては、■ ｉ）
Ｈを低下させてｔ！Ｉｍする方法は、ある程度の効果が
得られるが、エキスの種類によってはｐＨ調整により品
質変化を生ずる。
■ フレーバーカットバンクは、濃縮条件によっては熱
変化を起こしカットバックしたフレーバーを戻しても抽
出液の品質を再現しない。
■ 膜濃縮は、浸透圧の関係上高濃度の濃縮は不可能で
ある。
■ 一方、抽出液特有の風味を維持すべく抽出液を冷凍
し、市販しているものもあるが、低濃度である点及び流
通経費負担で単位エキス濃度当りのコストが高い。
以上のごとき問題点が挙げられ、これらの従来法による
場合、抽出液の待つ特有の風味を保持した濃縮エキスを
得るに至っていない。
従って、本発明はエキスの種類等の如何に関わらず常に
抽出液の持つ特有の風味を保持した濃縮エキスを低コス
トで得ることを目的としたものである。[Industrial Application Field] The present invention relates to a manufacturing method for obtaining a concentrated extract without impairing the unique flavor of the extract. [Prior Art] Conventional a-condensed extracts have a weak flavor, so in the authentic market, low-concentration frozen extracts and retort extracts that are not concentrated are growing. However, these low-concentration extracts have high distribution costs and are difficult to process, so there is a demand for concentrated extracts with strong flavors. Regarding the flavor of concentrated extracts, there is little interest in the temperature conditions during concentration, perhaps because conventional extracts are extracted using hot water extraction, and it is thought that quality deterioration during concentration is solely due to volatilization of flavor components. was. For this reason, technological developments from the viewpoint of flavor volatilization are being developed here and there. Specifically, (1) When the livestock meat extract-based distillate is basic, the pH of the liquid to be concentrated is made acidic to suppress flavor volatilization. ■ Concentrate the distillate by rectification or membrane concentration and add to the concentrate. (Flavor Cuffed Pack Method) ■ Concentrates mainly vegetable extracts using reverse osmosis membranes. Although there are examples such as those mentioned above, most concentrates focus on the behavior of flavor components. Vacuum concentration is used as the concentration condition, but this method focuses on the evaporation ability (heating temperature is approximately 100 to 130°C and the evaporation temperature is as low as possible), and there is no consideration from the perspective of heating temperature and quality. [Problems to be solved by the invention] Problems with such conventional technology include ■ i)
Lower H and t! Although the Im method is effective to some extent, the quality may change depending on the type of extract due to pH adjustment. ■ Depending on the concentration conditions, Flavor Cut Bank may undergo thermal changes and the quality of the extract may not be reproduced even if the flavor that was cut back is restored. ■ Membrane concentration cannot achieve high concentrations due to osmotic pressure. (2) On the other hand, in order to maintain the unique flavor of the extract, some frozen extracts are commercially available, but the cost per unit extract concentration is high due to the low concentration and distribution costs. Due to the above-mentioned problems, these conventional methods have not resulted in obtaining a concentrated extract that retains the unique flavor of the extract. Therefore, the object of the present invention is to obtain at a low cost a concentrated extract that always retains the unique flavor of the extract, regardless of the type of extract.
【問題点を解決するための手段〕[Means to solve problems]
本発明者らは、上記課題の解決のため、濃縮時の風味劣
化挙動につき研究を重ね、濃縮時の風味劣化はフレーバ
ーの揮散が一つの要因となるも、熱変化によるものが支
配的であり、エキス濃度が高くなるに従い、濃縮時の加
熱温度が品質劣化に大きな影響を及ぼし、特に畜肉エキ
ス系においてこの傾向が顕著であるとの知見を得た０本
発明は、かかる知見に基づき、ｔｉｍ１１１条件、濃縮
装置につき更に鋭意検討を重ねた結果完成されたもので
ある。
本発明において対象となるエキスとしては、ビーフエキ
ス、ボークエキス等の畜肉エキス、チキンエキス等の家
禽肉エキス、チキン、ボーク等のガラエキス、ホタテエ
キス、カニエキス、エビエキス等の魚介エキス、タマネ
ギエキス、ネギエキス、ニンジンエキス等の野菜エキス
、シイタケエキス等の茸エキス等の各種動植物エキスが
挙げられ、特にガラエキスにおいて本発明の適用による
効果が顕著である。
以下、鶏ガラエキスを例にして述べる。
エキスの原料となる鶏ガラを必要に応じて前処理し、熱
水抽出を行う、熱水抽出の条件は特に限定されていない
が、熱水抽出段階での温度、時間の条件は製品品質に大
きな影響を与えるため、最適な条件を設定し、エキス固
形分濃度０．５〜１０％程度になるように抽出を行う、
抽出液のエキス濃度が、低すぎる場合、濃縮に時間がか
かり好ましくない。また、濃度を高くするため過度に高
温、長時間の抽出を行うとエキスの品質が悪くなる。
抽出液としては、エキス固形分濃度０．５〜１０％程度
となるように原料対水の比率、抽出条件などを設定する
。得られた抽出液を必要に応じ酵素処理する。
酵素処理は、具体的には市販の微生物起源のエンド型プ
ロテアーゼを抽出液に抽出液の固形分当り０．２〜１．
０％添加し、その温度を４５〜５５℃の範囲で０．５〜
１時間程度保持し分解を行う、その後９０℃まで温度を
上げ１０分間保持し酵素を失活させたあと急冷する。
酵素処理した抽出液を加熱温度９０℃以下で濃縮する０
本発明者らは、濃縮時の加熱温度、蒸発温度と品質劣化
との関係を検討し、蒸発温度が６０℃以上では、品質劣
化が著しいことを認めた。また、蒸発温度が６０℃以下
の範囲で同一の場合、加熱温度を６０℃以上にするとそ
の加熱温度によって、ある濃度以上になると品質劣化を
起こし始める限界濃度があり、加熱温度を高くするに従
いその限界濃度は、低くなる。１００〜１３０℃の加熱
温度、即ち、従来の濃縮条件で濃縮すると濃縮物の品質
は、著しく劣化する。加熱温度が９０℃程度であれば、
固形分濃度３０％程度の濃縮度においては満足できる品
質の物が得られるが保存性、流通コスト等を考慮すると
エキス濃度は、高い程望ましいので加熱温度は、９０℃
または、それより低い温度、好ましくは７０℃以下、更
に好ましくは６０℃以下に設定する。加熱温度の下限は
、蒸気圧との関連で３０℃近辺である。
温度以外の濃縮条件および濃縮に使用する装置は、固形
分濃度が４０％以下であれば特に限定されないが、固形
分濃度が３０％以上もしくは４０％以上の濃縮エキスを
得る場合は、総括伝熱係数の高い濃縮条件及び機種を選
ぶことが望ましい。
なぜならば、エキスの濃縮時の品質劣化は、主として熱
負荷がかかることによって起こるが、同一温度条件で濃
縮する場合、総括伝熱係数が高いほど熱負荷が小さくな
るからである。
この点から被濃縮液の粘度は、それが高くなれば総括伝
熱係数が低下するため低い方が望ましい。
実際に例えば、豚骨、鶏ガラの抽出液を予めプロテアー
ゼ処理し、濃縮時の被濃縮液の粘度を低下させることに
より品質劣化を起こし始める限界濃度は、大幅に上がり
高濃度のエキスを得ることができる。
鶏ガラエキスの場合、濃縮時の加熱温度６５℃において
未酵素処理で固形分濃度３５％、酵素処理で５０％程度
まで風味劣化を伴わずにｔ！ＩＩＩすることができる。
濃縮に使用する機種については、総括伝熱係数の点で優
れている遠心薄膜：ａ縮機が好適である。
遠心薄膜濃縮機は、更に、図４に示すように濃縮対象と
なるエキスが蒸発面上で遠心力により薄層となり、加熱
を受けると同時に瞬間的に水分が蒸発し冷却されるとい
う特徴をもっている。従って従来の濃縮機即ち、加熱部
と蒸発部との間に距離があり、加熱にさらされる時間が
長い装置に比べ加熱による影響が極めて小さいという利
点もある。
以下、実験例、実施例により本発明を更に説明する。
【実験例１】
常法に従い熱水抽出した固形分濃度２〜３％のチキンガ
ラエキスにつき、酵素未処理と酵素処理を施した２つの
サンプルに分け、濃縮加熱温度６５、ＴＯ，８０，９０
℃、蒸発温度３０℃で遠心ＵＩｌ濃縮濃縮法り各々濃縮
した。
得られた濃縮エキスをそれぞれ固形分濃度０．８％にな
るように熱水で希釈し、希釈液の味、風味を訓練された
パネルで官能評価した。
結果は、第１．２図に示すとおりであり以下の３点が明
かになった。
■ 濃縮時の加熱温度と品質には、相関があり、品質劣
化を起こす限界濃度は、加熱温度を低くするに従い高く
なる。
■ ９０℃の加熱温度で濃縮すると酵素未処理では、固
形分濃度約１０％で品質劣化を生じるが、酵素処理を施
すことにより固形分濃度約３０％まで品質劣化を生じる
ことなく濃縮することが可能である。−船釣な濃縮エキ
スは、固形分濃度３０％程度の濃度で市販されているも
のもあり、９０℃の加熱温度であれば一応満足のい（品
質のものが得られる。
■ しかしながら、保存性、流通コスト等を考慮すると
エキス濃度は、高いほど望ましく、９０℃以下の加熱温
度であればより一層本発明の効果が発揮される。
〔実験例２〕
実験例１で濃縮時の加熱温度によって品質劣化の起こる
濃度が異なることに着目し、エキスの熱履歴と品質の関
係について実験を行った。
実施例１と同様に熱水抽出し、酵素処理した固形分濃度
２〜３％のチキンガラエキスを濃縮加熱温度６５℃蒸発
温度３０℃の条件下で薄膜濃縮機により固形分濃度４０
％まで濃−縮した。この濃縮エキスを１００ｇずつパウ
チ包装し、試料とした。
この試料数点を６０℃、７０’ｅ、８０ｔ’の各温度の
温水に浸し、その中身のエキスが達温後一定時間毎に試
料を取り出し、エキスの品質を評価した。
結果を第３図に示したが、それより以下の２点が判明し
た。
■ ６０℃では、２時間放置してもエキスの品質劣化を
殆ど認められないが、７０．８０’ｅの温度領域では、
急激な品質劣化が起こり、明らかに６０℃の場合とは、
異なった挙動を示す、このことから、エキスによっては
、濃度が高いところでは、ある温度に達するとエキスの
品質に大きな影響をあたえる成分が熱変化を起こしエキ
ス自体の品質が損なわれるということを示している。
■ チキンガラエキスは、劣化を起こし始める温皮帯が
６０〜７０℃の範囲にあることを示しており品質劣化の
少ない高濃度の濃縮エキスを得るには、濃縮時の蒸発温
度及び加熱温度共に６０℃以下にすることが望ましい。
〔実施例１〕
実験例１と同様に熱水抽出し、酵素処理した固形分濃度
２〜３％のチキンガラエキスを薄膜濃縮機にて下記の条
件で固形分濃度４０％まで濃縮した。この各サンプルを
実験例１と同様の方法で評価した。
結果は、表１に示すように一般的な濃縮条件である加熱
温度１００〜１２０℃と本発明の知見である加熱温度７
０℃とには、明らかに差が認められ、本発明の有用性を
立証できた。
表１ 遠心薄膜濃縮機による加熱温度
と品質の関係
但し、０・・・抽出液に近く、良質。
・・・・○より品質やや劣るが大差なし。
Δ・・・風味も弱くなり、エキス感もなくなる。
×・・・ムレ奥がたち、エキス感も無く、水っぽくなる
。
〔実施例２〕
実験例１と同様の方法で得た固形分濃度２〜３％のチキ
ンガラエキスを酵素処理しこれを用いて、強制循環型カ
ランドリア濃縮機と遠心薄膜濃縮機各々で濃縮した。こ
の各サンプルを実験例１同様の方法で評価した。
結果は、表２に示すように遠心薄膜濃縮機による濃縮が
カランドリア濃縮機による濃縮に比べて品質劣化度合が
小さい、即ち、同じ加熱温度であっても使用する濃縮機
によって品質劣化の度合が異なり、遠心薄膜濃縮機がエ
キスの品質劣化を抑える濃縮機として好適である。
〔発明の効果〕
本発明法により、従来のＩ！縮では、再現できなかった
抽出液の持つ特有の風味を有する品質劣化の少ない濃縮
エキスが得られ、且つ、その濃縮加熱温度の選択により
任意のエキス濃度の濃縮エキスを高品質で得ることがで
きる。In order to solve the above-mentioned problems, the present inventors have conducted repeated research on flavor deterioration behavior during concentration, and found that although flavor volatilization is one factor in flavor deterioration during concentration, heat change is the dominant factor. It was found that as the extract concentration increases, the heating temperature during concentration has a large effect on quality deterioration, and this tendency is particularly remarkable in livestock meat extract systems.The present invention is based on this knowledge, It was completed as a result of further intensive studies regarding the conditions and concentration equipment. Extracts targeted in the present invention include livestock extracts such as beef extract and bok extract, poultry extracts such as chicken extract, gala extract such as chicken and bok extract, seafood extracts such as scallop extract, crab extract, and shrimp extract, onion extract, green onion extract, Examples include various animal and plant extracts such as vegetable extracts such as carrot extract, mushroom extracts such as shiitake extract, and the effect of the present invention is particularly remarkable in the use of gala extract. Below, chicken bone extract will be described as an example. The chicken bones, which are the raw materials for the extract, are pretreated as necessary and then subjected to hot water extraction.The conditions for hot water extraction are not particularly limited, but the temperature and time conditions at the hot water extraction stage depend on the quality of the product. In order to have a big impact, we set the optimal conditions and perform extraction so that the extract solid content concentration is about 0.5 to 10%.
If the extract concentration of the extract is too low, it will take a long time to concentrate, which is not preferable. Furthermore, if extraction is performed at excessively high temperatures and for a long time in order to increase the concentration, the quality of the extract will deteriorate. As for the extract, the ratio of raw material to water, extraction conditions, etc. are set so that the extract solid content concentration is about 0.5 to 10%. The obtained extract is treated with an enzyme if necessary. Specifically, in the enzyme treatment, a commercially available endo-type protease of microbial origin is added to the extract in an amount of 0.2 to 1.0% per solid content of the extract.
0% addition, and the temperature was 0.5 to 45 to 55℃.
The temperature is maintained for about 1 hour to perform decomposition, and then the temperature is raised to 90°C and maintained for 10 minutes to inactivate the enzyme, followed by rapid cooling. Concentrate the enzyme-treated extract at a heating temperature of 90℃ or less0
The present inventors investigated the relationship between heating temperature during concentration, evaporation temperature, and quality deterioration, and found that quality deterioration is significant when the evaporation temperature is 60° C. or higher. In addition, when the evaporation temperature is the same within the range of 60℃ or less, if the heating temperature is increased to 60℃ or higher, there is a critical concentration that starts to cause quality deterioration when the concentration exceeds a certain concentration. The critical concentration will be lower. When concentrated at a heating temperature of 100 to 130°C, ie, conventional concentration conditions, the quality of the concentrate deteriorates significantly. If the heating temperature is about 90℃,
A product of satisfactory quality can be obtained at a concentration of about 30% solid content, but considering storage stability, distribution costs, etc., a higher extract concentration is desirable, so the heating temperature is 90°C.
Alternatively, the temperature is set lower than that, preferably 70°C or lower, more preferably 60°C or lower. The lower limit of the heating temperature is around 30°C in relation to vapor pressure. The concentration conditions other than temperature and the equipment used for concentration are not particularly limited as long as the solid content concentration is 40% or less, but when obtaining a concentrated extract with a solid content concentration of 30% or more or 40% or more, general heat transfer It is desirable to select concentration conditions and a model with a high coefficient. This is because quality deterioration during concentration of an extract mainly occurs due to heat load, but when concentrating under the same temperature conditions, the higher the overall heat transfer coefficient, the smaller the heat load. From this point of view, it is desirable that the viscosity of the liquid to be concentrated be low, since the higher the viscosity, the lower the overall heat transfer coefficient. In fact, for example, by pre-treating pork bone and chicken bone extracts with protease to lower the viscosity of the concentrated liquid during concentration, the critical concentration at which quality deterioration begins can be significantly raised, making it possible to obtain highly concentrated extracts. I can do it. In the case of chicken bone extract, at a heating temperature of 65°C during concentration, the solid content concentration can reach 35% without enzyme treatment, and up to about 50% with enzyme treatment, without any flavor deterioration! III. As for the model used for concentration, a centrifugal thin film:A condenser is suitable because it has an excellent overall heat transfer coefficient. As shown in Figure 4, the centrifugal thin film concentrator has the additional feature that the extract to be concentrated forms a thin layer on the evaporation surface due to centrifugal force, and as soon as it is heated, the moisture evaporates instantaneously and it is cooled. . Therefore, compared to conventional concentrators, which have a distance between the heating section and the evaporation section and are exposed to heat for a long time, there is an advantage that the influence of heating is extremely small. The present invention will be further explained below using experimental examples and examples. [Experiment Example 1] Chicken gut extract with a solid content concentration of 2 to 3% was extracted with hot water according to a conventional method, divided into two samples, one without enzyme treatment and the other with enzyme treatment, and concentrated at a heating temperature of 65, TO, 80, 90.
℃, and the evaporation temperature was 30℃ using the centrifugal UIl concentration method. The obtained concentrated extracts were each diluted with hot water to a solid content concentration of 0.8%, and the taste and flavor of the diluted solutions were sensory evaluated by a trained panel. The results are shown in Figure 1.2, and the following three points were made clear. ■ There is a correlation between heating temperature during concentration and quality, and the lower the heating temperature, the higher the critical concentration that causes quality deterioration. ■ When concentrated at a heating temperature of 90°C, quality deterioration occurs at a solid content concentration of approximately 10% without enzyme treatment, but with enzyme treatment, it is possible to concentrate up to a solid content concentration of approximately 30% without quality deterioration. It is possible. - Some concentrated extracts are commercially available with a solid content concentration of about 30%, and if heated at a heating temperature of 90°C, they will be of satisfactory quality (quality can be obtained.) However, the shelf life is , Considering distribution costs, etc., the higher the extract concentration is, the more desirable it is, and the effects of the present invention will be even more effective if the heating temperature is 90°C or less. [Experimental Example 2] Depending on the heating temperature during concentration in Experimental Example 1, Focusing on the fact that the concentration at which quality deterioration occurs is different, we conducted an experiment on the relationship between the thermal history of the extract and its quality. Chicken bones with a solid content concentration of 2 to 3% were extracted with hot water and treated with enzymes in the same manner as in Example 1. Concentrate the extract to a solid content concentration of 40 using a thin film concentrator at a heating temperature of 65°C and an evaporation temperature of 30°C.
%. This concentrated extract was packaged in 100 g pouches and used as samples. Several of these samples were immersed in hot water at temperatures of 60° C., 70'e, and 80 t', and after the contents of the extract reached temperature, samples were taken out at regular intervals to evaluate the quality of the extract. The results are shown in Figure 3, and the following two points were found. ■ At 60℃, there is almost no deterioration in the quality of the extract even after leaving it for 2 hours, but in the temperature range of 70.80'e,
Sudden quality deterioration occurs and it is obvious that at 60℃,
This indicates that, depending on the extract, when the concentration is high, when a certain temperature is reached, the components that have a large effect on the quality of the extract undergo a thermal change, which impairs the quality of the extract itself. ing. ■ Chicken cara extract shows that the warm skin zone where deterioration begins is in the range of 60 to 70℃.In order to obtain a highly concentrated concentrated extract with little quality deterioration, both the evaporation temperature and heating temperature during concentration must be adjusted. It is desirable to keep the temperature below 60°C. [Example 1] Chicken gut extract having a solid content concentration of 2 to 3%, which was subjected to hot water extraction and enzyme treatment in the same manner as in Experimental Example 1, was concentrated to a solid content concentration of 40% using a thin film concentrator under the following conditions. Each sample was evaluated in the same manner as in Experimental Example 1. As shown in Table 1, the results are as follows: heating temperature 100 to 120°C, which is a general concentration condition, and heating temperature 7, which is the knowledge of the present invention.
A clear difference was observed from 0°C, proving the usefulness of the present invention. Table 1 Relationship between heating temperature and quality using centrifugal thin film concentrator However, 0: Close to extract, good quality. ...The quality is slightly inferior to ○, but there is no big difference. Δ...The flavor becomes weaker and the extract feeling is lost. ×...It gets stuffy, has no essence, and becomes watery. [Example 2] Chicken gut extract with a solid content concentration of 2 to 3% obtained in the same manner as in Experimental Example 1 was treated with enzymes and used to concentrate using a forced circulation calandria concentrator and a centrifugal thin film concentrator. . Each sample was evaluated in the same manner as in Experimental Example 1. As shown in Table 2, the results show that concentration using a centrifugal thin film concentrator has a smaller degree of quality deterioration than concentration using a calandria concentrator.In other words, even at the same heating temperature, the degree of quality deterioration varies depending on the concentrator used. A centrifugal thin film concentrator is suitable as a concentrator that suppresses deterioration of extract quality. [Effect of the invention] The method of the present invention enables the conventional I! By condensation, a concentrated extract with a unique flavor of the extract that could not be reproduced with little quality deterioration can be obtained, and by selecting the concentration heating temperature, a high quality concentrated extract with an arbitrary extract concentration can be obtained. .
【図面の簡単な説明】[Brief explanation of drawings]
第１図は酵素処理したエキスの濃縮時の加熱温度の品質
への影響を、第２図は酵素未処理エキスの濃縮時の加熱
温度の品質への影響を、第３図は濃縮エキスを各温度に
保持した時の品質劣化のタイムコースをそれぞれ示し、
第４図は強制循環型濃縮機（カランドリア）、第５図は
遠心薄膜型濃縮機の略断面図をそれぞれ示す。
第４図及び第５図中
１・・・真空源、２・・・供給液、３・・・濃縮液、４
・・・蒸気、 ５・・・加熱部、６・・・トラップト・
・蒸発部、８・・・循環ポンプ。
第
関
（蒸発温度３０℃）
第１
時間（分）
第４図
第
図Figure 1 shows the effect of heating temperature on quality during concentration of enzyme-treated extract, Figure 2 shows the effect of heating temperature on quality during concentration of enzyme-untreated extract, and Figure 3 shows the effect of heating temperature on quality of concentrated extract. Each shows the time course of quality deterioration when kept at a certain temperature,
FIG. 4 shows a schematic sectional view of a forced circulation type concentrator (calandria), and FIG. 5 shows a schematic sectional view of a centrifugal thin film type concentrator. In Figures 4 and 5, 1... Vacuum source, 2... Supply liquid, 3... Concentrate liquid, 4
...Steam, 5.Heating part, 6.Trapped.
・Evaporation section, 8...Circulation pump. No. 1 (evaporation temperature 30℃) 1st time (minutes) Fig. 4 Fig.