Study on the application of high pressure to food improvement with new texture and function

当1,000-10,000大气压的高压作用于食品原料时，蛋白质会变性和凝结，酶会失活，微生物会被杀死。通过将这些现象应用于食品加工和保鲜，获得了以下结果。在1,000~3,000大气压下对浓缩乳清蛋白进行酶解，并选择性地消化乳球蛋白。产物的电泳法和免疫学分析表明，球蛋白完全消失，乳清蛋白完好无损。本研究也为改善大豆蛋白的性质开辟了一条新的途径。利用3,000~6,000 atm制备了蛋清、蛋黄、肉、鱼肉、大豆蛋白凝胶，并对其质构和感官特性进行了分析。结果表明，这些凝胶具有较高的营养价值和良好的消化率，在质构上与生火腿和卡马博科斯相似。高压处理增加了淀粉酶消化的敏感性。考察了不同盐类和醇类的影响，以获得高品质的淀粉消化液。利用高压成功地灭活了鸡蛋、清酒和果汁中的微生物。结果表明，高压处理能有效地保持食品的天然风味，是一种应用于食品加工、保鲜和杀菌的新技术。这项技术与热处理不同，因为压力对天然风味没有影响。现在，需要进行工业用途的研究。

When high hydrostatic pressure of 1,000-10,000 atm is applied to food materials, protein is denatured and coagulated, enzymes are inactivated, and microoganisms are killed. By applying these phenomena to food processing and preservation, following results were obtained.1. Enzymatic proteolysis of milk whey protein concentrates was performed under 1,000 to 3,000 atm, and -lactoglobulin was selectively digested. Electrophoresis and immunological analysis of the product thus obtained showed complete loss of the globulin, remaining -lactalbumin intact. This study also opens a way to improve properties of soybean proteins.2. Gels of egg white and yolk,meat fish meats, and soy proteins were prepared by applying 3,000 to 6,000 atm, and their texture and organoleptic properties were analyzed. As results, these gels showed high nutritive values and good digestibility and resembled raw hams and Kamabokos in texture.3. The treatment of starches with high pressure resulted in the increased susceptibility of amylase digestion. Effects of various salts and alcohols were investigated to obtain starch digests of high quality.4. Microorganisms in egg, sake, and juices was successfully inactivated with use of high pressure. These results showed that the high pressure treatment is effective to preserve these foods with keeping their natural flavour.From results thus obtained, use of high pressure is concluded to be a new technique which is applied to food processing, preservation and sterilization. The technique is different from heat-treatment because pressure has no effect on the natural flavour. Now, studies for industrial use are needed.