不同贮藏蔬菜中亚硝酸盐变化的研究

本研究以大白菜、甘蓝、白萝卜为试验材料,研究了室温、低温、腌制三种贮藏蔬菜中亚硝酸盐含量的变化及其形成的机理。结果表明:室温、腌制两种贮藏方法的初期都出现“亚硝峰”。形成“亚硝峰”的原因依贮藏方法而异,室温贮藏蔬菜中“亚硝峰”的形成是由于采摘后菜体内硝酸还原酶的活性增强导致蔬菜内硝酸盐还原成亚硝酸盐;腌制贮藏蔬菜中“亚硝峰”的形成是由于发酵过程中杂菌所致。腌制菜中“亚硝峰”的峰值大大高于室温贮藏,并超过FAO/WUO规定的ADI值,腌制后期亚硝酸盐含量在安全食用范围。室温、低温贮藏蔬菜中亚硝酸盐含量的最高值小于ADI值,可以放心食用。

Study on Nitrite Formation of Vegetables Stored in Varied Storage Conditions

Nitrite content variation and nitrite formation mechanics of the vegetables, respectively stored in different room- temperatures, low temperatures and natural fermentations, are studied in this paper. And the test materials are varieties of Chinese cabbage, cabbage and white radish. The results show that the nitrite peaks appear in the initial stage (3days storge) in the three kinds of storage methods. The main reasons for nitrite peak formation of the varied treatments are different. When vegetables were plucked, their nitrate reductase activity increased. So the main reason for nitrite peak formation of vegetables stored in room-temperature and low temperature, is the reduction of nitrate into nitrite by vegetable's nitrate reductase, where, nitite peak formation was caused by microorganisms in the course of fermentation. This peak value is much higher than that of the two other treatments in excesse of the ADI value established by FAO/WHO. But the nitrite content is in the safety edible range in the anaphasic stage (in the latter stage of storage 8 dags latter). The nitrite content value of the vegetables stored in room- temperature and low temperature is lower ADI value, so the vegetables are edibly safe.