食品加工工艺对大豆内源基因降解变化规律的影响

本文以转基因大豆和非转基因大豆为试验材料，运用定性PCR技术分析了磨浆、煮浆、调配、均质、点浆、杀菌、喷雾干燥等豆腐、豆奶、豆粉三种豆制品中关键加工工艺对大豆内源基因lectin的影响，探讨了转基因大豆加工食品在不同加工过程中DNA降解程度的变化。研究结果表明，大豆内源基因在三种加工食品中的各个加工过程中都会受到不同程度的破坏。在豆腐、豆奶、豆粉的加工过程中，片段大小为1883bp的lectin基因仅能在原料中检测到；磨浆、煮浆、均质等工艺，使lectin基因降解至1000bp以下；随着进行的点浆、高温杀菌或喷雾干燥等工艺对lectin基因的降解产生更显著的影响，豆腐终产品中lectin基因的片段大小在500bp以下，豆奶、豆粉中lectin基因片段大小仅为200bp左右。

Nucleic Acid Elimination During Different Manufacturing Processes of Soybean Products

The degradation of DNA of gene-transfered soybean during manufacturing process of Tofu, soymilk, and soybean flour milling, including various steps, such as cooking, blending, homogenizing, sterilizing, and spray drying were examined using a sensitive polymerase chain reaction detection system. The system used specific amplification of Roundup Ready soybean endogenous gene. The results show that the lectin gene is degraded during the manufacturing process of these soybean products, and the fragment size 1883 bp can only be detected in the raw material. After milling, cooking and homogenizing, the lectin gene fragment is degraded to <1000 bp. The following processes, sterilizing and spray drying exhibit significant effect on degradation of the lectin gene. The fragment size of lectin gene in final product is less than 500bp in Tofu and around 200bp in soymilk and soy flour.