CAJ | 학술논문

为了探讨高密度CO2（dense phase carbon dioxide，DPCD）处理对虾仁肌肉品质的影响，以未处理的新鲜虾仁为对照，研究了DPCD处理过程中虾仁营养组成和水分子状态的变化规律。结果表明：在温度35～55℃和压力5～25 MPa的条件下处理10～50 min，与未处理虾仁相比，虾仁的水分、粗蛋白、粗脂肪和灰分含量均显著下降（P＜0.05），尤其是脂肪含量下降幅度最大；随着DPCD处理强度增加，虾仁肌浆蛋白和肌原纤维蛋白含量显著降低（P＜0.05），肌基质蛋白含量显著增加（P＜0.05）；随着DPCD处理强度增加，虾仁结合水自由度升高，而不易流动水和自由水的自由度下降，且结合水和自由水的比例显著升高（P＜0.05），不易流动水的比例显著下降（P＜0.05）。DPCD在55℃和15 MPa处理虾仁30 min，虽然可以达到完全杀菌效果，但是水分、粗蛋白、粗脂肪、灰分质量分数分别下降了7%、3%、25%和11%，肌浆蛋白和肌原纤维蛋白发生较大变性，自由水比例显著增加（P＜0.05）。研究结果将为DPCD技术在对虾加工中的应用提供参考。
위료탐토고밀도CO2（dense phase carbon dioxide，DPCD）처리대하인기육품질적영향，이미처리적신선하인위대조，연구료DPCD처리과정중하인영양조성화수분자상태적변화규률。결과표명：재온도35～55℃화압력5～25 MPa적조건하처리10～50 min，여미처리하인상비，하인적수분、조단백、조지방화회분함량균현저하강（P＜0.05），우기시지방함량하강폭도최대；수착DPCD처리강도증가，하인기장단백화기원섬유단백함량현저강저（P＜0.05），기기질단백함량현저증가（P＜0.05）；수착DPCD처리강도증가，하인결합수자유도승고，이불역류동수화자유수적자유도하강，차결합수화자유수적비례현저승고（P＜0.05），불역류동수적비례현저하강（P＜0.05）。DPCD재55℃화15 MPa처리하인30 min，수연가이체도완전살균효과，단시수분、조단백、조지방、회분질량분수분별하강료7%、3%、25%화11%，기장단백화기원섬유단백발생교대변성，자유수비례현저증가（P＜0.05）。연구결과장위DPCD기술재대하가공중적응용제공삼고。
Dense phase carbon dioxide (DPCD) is a non-thermal processing technology, which affects microorganisms and enzymes through molecular effects of CO2 under pressures below 50 MPa and 60℃. DPCD has had less of a significant effect on the quality of food and has been applied to the process of meats, vegetables, seeds and food powders, fruits, spices and herbs, and fish. Currently, most of research are more focused on microorganisms and enzymes that are inactivated by DPCD. However, some research indicated that DPCD has an effect on the quality of meat and its products, mainly related to muscle pH value, color, water holding capacity, texture, etc. The nutritional composition of meat and its products also has a decisive effect on their qualities. Water is the highest content in meat and its products composition. Water can directly affect color, tenderness, juiciness, flavor, and the processing characteristics of meat and its products. Water content and its distribution showed dynamic changes in the processing and storage of meat and its products, which is an important factor in determining quality and shelf life. Litopenaeus vannamei is a favorite of consumers in aquatic products due to tender meat and high nutritional value. In our previous study, Litopenaeus vannamei was treated for sterilization and inactivation of polyphenol oxidase by DPCD. In order to further investigate the effect of DPCD on shrimp muscle quality, peeled shrimp were used as the studied object. The effects of temperature (35-55℃), pressure (5-25 MPa), and time (10-60 min) on nutritious components and water molecules of shrimp muscle were studied. The results showed as follows: when using the untreated peeled shrimp, the content of nutritious components (moisture, crude protein, crude fat, and ash), especially fat, significantly decreased (P<0.05) after DPCD treatment. With the increasing of DPCD treatment intensity, fat was extracted and water was dried out by DPCD. Partially ionized minerals and small molecular compounds containing nitrogen (e.g. free amino acids) were carried out with CO2 in the unloading process. While using the untreated peeled shrimp, the contents of myofibrillar and sarcoplasmic protein decreased significantly (P<0.05) and the content of insoluble protein increased significantly (P<0.05) with exposure to time, temperature, and pressure when DPCD was increasing. The reason for that was myofibrillar and sarcoplasmic protein were denatured and transformed to insoluble protein by DPCD. The results of low field nuclear magnetic resonance (LF-NMR) showed that peeled shrimp contained four kinds of water molecules with different mobility. With exposure to time, temperature, and pressure when DPCD was increasing, the degree of freedom of bound water increased while the degree of freedom of immobilized water and free water decreased. Nonetheless, the content of bound water and free water increased significantly (P<0.05) while the content of immobilized water decreased significantly (P<0.05), when the peeled shrimp was treated for 30 min at 15 MPa and 55℃ of DPCD. Microorganism and PPO from Litopenaeus vannamei were inactivated, but the content of moisture, crude protein, crude fat, and ash decreased by 7%、3%、25%, and 11%, respectively. Sarcoplasmic and myofibrillar protein were denatured, and the free water ratio increased significantly (P<0.05). The research results will provide a reference for the application of DPCD in shrimp processing.