【発明の詳細な説明】[Detailed description of the invention]
(イ) 産業上の利用分野
この発明は、ホタテ貝の毒素除去法に関する。
(ロ) 従来の技術
近年、ホタテ貝の養殖海面に、Gonyaulax属
等のプランクトンが発生して、これらのプランク
トンを摂取したホタテ貝が毒性を帯びたり、ある
いは工業排水中に含まれるヒ素、カドミウム、水
銀等の重金属を吸収し、このホタテ貝が原因の中
毒症が発生し、また、このためにホタテ貝の販売
が停止して養殖業者が大損害を蒙るということが
頻発している。
そこで、この毒性を帯びたホタテ貝を無毒化す
る研究が行われ、ホタテ貝の剥き身を大量の水で
洗浄して毒素を洗い流す、あるいは、高温にて煮
沸する等の方法が講じられたが、いずれも完全な
毒素除去ができず、また、ホタテ貝の風味を損う
という欠点があつた。
(ニ) 問題点を解決するための手段
この発明では、ホタテ貝を、減圧条件下にて加
熱油中に浸漬して、加熱油による加熱処理を行な
い、さらに加熱処理した処理物より脱油処理し
て、ホタテ貝から毒素を除去することを特徴とす
るホタテ貝の毒素除去法を提供せんとするもので
ある。
(ホ) 作用・効果
この発明によれば、ホタテ貝を減圧条件下にお
いて加熱油中に浸漬することにより、同剥き身に
含まれた水中の不溶性の毒素が加熱油中に溶出
し、しかも、減圧条件下での加熱により、同ホタ
テ貝の細胞組織中の水分の蒸散が促進され、水分
蒸発後の組織空洞内に加熱油が深く浸透して、同
水分と加熱油との置換が、常圧下における水油置
換よりも活発に行われて、組織中の毒素が加熱油
中に溶け込んで、その処理物を脱油することによ
つて毒素除去が行われるもので、毒性を帯びたホ
タテ貝を、無毒の食用に適したものとすることが
でき、しかも、減圧条件下での処理であるから比
較的低温、かつ短時間で上記処理が完了するので
ホタテ貝の風味を損わず、また、処理後のホタテ
貝は脱水乾燥しているので長期保存が可能であ
る。
さらに、ホタテ貝が加熱油に浸漬した際に、同
ホタテ貝に含まれる重金属等（カドミウム、ヒ
素、水銀等）を加熱油中に溶出させて、この重金
属類が加熱油中に移行して、ホタテ貝から重金属
類を除去することもできる。
(ヘ) 実施例
本発明の実施例を詳細に説明すれば、容量4.5
立方米のクツカー中に動物油、植物油、鉱物油、
動植物油脂等の単一油又は混合油を投入し、同油
を60〜120℃の一定温度に加熱して加熱油として
おく。
次に、上記加熱油中に、略250Kgの毒性を帯び
たホタテ貝を投入浸漬してクツカーを閉蓋する。
次に、加熱油を60〜120℃の一定温度に保持し
ながら、クツカー内を撹拌し、更にクツカー内を
減圧状態とする。
かかる減圧処理は、ホタテ貝の加熱油への浸漬
後の初期30分程度は、蛋白質が熱凝固し易い軽度
の減圧条件下、即ち、常圧より10〜20mmHgの減
圧を行い、次いで、強度の減圧条件、即ち、常圧
より740〜750mmHgの強度減圧条件下で約60分程
度の処理を行い、含水率３〜６％前後になるまで
処理する。
すなわち、減圧初期において、油温と常圧より
10〜20mmHgの軽度の減圧によつて、まず、ホタ
テ貝の水溶性蛋白質及びゼラチン質を凝固安定化
せしめ、これらの呈味成分及びビタミン類の流出
を防止し、処理中途からの常圧より740〜750mm
Hgの強度の減圧条件によつてホタテ貝に含まれ
た水分を蒸散せしめ、水分蒸発後の細胞組織の空
洞に加熱により粘度が低下した加熱油を浸透せし
めて、細胞組織中で水分と加熱油との置換を行
い、同組織中に含まれた毒素を加熱油中に溶出さ
せると共に組織内外からホタテ貝を加熱油を熱媒
体として加熱する。
次に、脱油処理したホタテ貝は、クツカーから
取り出され、ノルマルヘキサン等の有機溶媒にて
毒素が溶出した油を溶解抽出して脱油処理し、毒
素の除去を行うと共に、油分を略３〜６％まで脱
油して製品とする。
したがつて、ホタテ貝の呈味成分、蛋白質、ビ
タミン等の流出、変質を防止しながら完全な毒素
除去を行うものである。そこで、上記の方法によ
つて処理したホタテ貝を分析した結果を次の表に
示す。
(a) Industrial application field This invention relates to a method for removing toxins from scallops. (b) Conventional technology In recent years, plankton such as those of the genus Gonyaulax have been occurring on the sea surface where scallops are cultured, and scallops that have ingested these plankton may become toxic, or they may be exposed to arsenic, cadmium, etc. contained in industrial wastewater. Scallops absorb heavy metals such as mercury, which often causes poisoning, and this often causes the sale of scallops to stop, resulting in large losses for aquaculture companies. Therefore, research was conducted to detoxify the toxic scallops, and methods such as washing the peeled scallops with large amounts of water to wash away the toxins, or boiling them at high temperatures were used. None of them had the disadvantage of not being able to completely remove toxins, and also impairing the flavor of scallops. (d) Means for Solving the Problems In this invention, scallops are immersed in heated oil under reduced pressure conditions, heat treated with heated oil, and then the heat-treated product is deoiled. Therefore, it is an object of the present invention to provide a method for removing toxins from scallops, which is characterized by removing toxins from scallops. (E) Function/Effect According to this invention, by immersing scallops in heated oil under reduced pressure conditions, insoluble toxins contained in the water contained in the peeled scallops are eluted into the heated oil. Heating under these conditions promotes the transpiration of water in the cell tissue of the same scallop, and the heated oil penetrates deeply into the tissue cavity after water evaporation, and the water and heated oil are replaced under normal pressure. This method is more active than the water-oil replacement process in which the toxins in the tissues are dissolved into the heated oil, and the toxins are removed by de-oiling the processed product. It is possible to make the scallops non-toxic and suitable for human consumption.Moreover, since the processing is carried out under reduced pressure conditions, the above-mentioned processing can be completed at a relatively low temperature and in a short time, so that the flavor of the scallops is not impaired. After processing, the scallops are dehydrated and dried, so they can be stored for a long time. Furthermore, when scallops are immersed in heated oil, heavy metals (cadmium, arsenic, mercury, etc.) contained in the scallops are eluted into the heated oil, and these heavy metals are transferred into the heated oil. Heavy metals can also be removed from scallops. (f) Example To explain the example of the present invention in detail, the capacity is 4.5
Animal oil, vegetable oil, mineral oil,
A single oil or a mixture of animal and vegetable fats and oils is added, and the oil is heated to a constant temperature of 60 to 120°C to form heated oil. Next, approximately 250 kg of toxic scallops are immersed in the heated oil, and the container is closed. Next, while maintaining the heating oil at a constant temperature of 60 to 120°C, the inside of the cooker is stirred, and the pressure inside the cooker is reduced. In this vacuum treatment, for the initial 30 minutes or so after immersing the scallops in heated oil, the protein is easily coagulated under mild vacuum conditions, i.e., the pressure is reduced to 10 to 20 mmHg from normal pressure, and then the pressure is reduced to 10 to 20 mmHg from normal pressure. The treatment is carried out for about 60 minutes under reduced pressure conditions, that is, under strong reduced pressure conditions of 740 to 750 mmHg from normal pressure, until the water content reaches about 3 to 6%. In other words, at the beginning of depressurization, the oil temperature and normal pressure
By applying a slight pressure reduction of 10 to 20 mmHg, first, the water-soluble proteins and gelatin of the scallops are coagulated and stabilized, and the flavor components and vitamins are prevented from flowing out, and the pressure is lowered to 740°C from normal pressure in the middle of processing. ~750mm
The moisture contained in the scallops is evaporated under Hg's strong vacuum conditions, and the heated oil whose viscosity has been reduced by heating is infiltrated into the cavities of the cell tissue after the water evaporates. The toxin contained in the tissue is eluted into the heated oil, and the scallop is heated from inside and outside the tissue using the heated oil as a heat medium. Next, the deoiled scallops are taken out of the kutsuka, and the oil from which the toxins have been eluted is dissolved and extracted using an organic solvent such as n-hexane. The product is made by removing oil to ~6%. Therefore, toxins are completely removed while preventing leakage and deterioration of flavor components, proteins, vitamins, etc. of scallops. Therefore, the results of analysis of scallops treated by the above method are shown in the following table.
【表】
上記の表のように。本発明の方法によつて、加
熱油中にカドミウム、水銀、ヒ素等が流出して、
ホタテ中の量を減少させるものである。
なお、上記の油温による毒素除去に先立つて、
ホタテ貝を大量の水で洗浄して水溶性の毒素を溶
出させてもよい。
そして、毒素除去処理に引続き減圧条件下で脱
油処理を行うのであるが、この脱油処理はホタテ
貝を加熱油に浸漬する際、予め金網製の籠中にホ
タテ貝を収容しておき、毒素除去処理完了後、ク
ツカー内の加熱油を抜き取ることにより行われ
る。
さらに、この方法で処理された製品は乾燥状態
であり、長期保存可能であり、食用にするとき
は、水で原形に戻して調理するものである。[Table] As shown in the table above. By the method of the present invention, cadmium, mercury, arsenic, etc. flow out into the heated oil.
This reduces the amount in scallops. In addition, before removing toxins using the oil temperature mentioned above,
Scallops may be washed with copious amounts of water to leach out water-soluble toxins. Then, following the toxin removal treatment, deoiling treatment is performed under reduced pressure conditions. In this deoiling treatment, when immersing the scallops in heated oil, the scallops are placed in a wire mesh cage in advance. After the toxin removal process is completed, this is done by draining the heated oil inside the couture. Furthermore, the products processed in this way are dry and can be stored for a long time, and when eaten, they can be reconstituted with water and cooked.