Effects of different storage temperature and different washing methods on the content of nitrite in vegetables

The changes of nitrite contents in leaf vegetables,melon or fruit vegetables,and root or stem vegetables were tested under different storage time,two different storage temperature(room temperature(15-20 ℃) and lower temperature(4±1) ℃) and three different washing methods(tap water,salt water and abluent solution).The results showed that:(1) Under both room temperature and lower temperature,the nitrite contents in all investigated vegetables increased gradually with the extension of storage time from the first day to the fourth day.(2)Under the same storage time and washing method,the nitrite contents and its chang speed in vegetables stored under lower temperature were both obviously lower than that stored under room temperature.(3)In contrast to tap water,both salt water and abluent solution could eliminate nitrite,but the efficiency of abluent solution was better than that of salt water.(4)The nitrite contents and its change speed in leaf vegetables was obviously higher than that in melon or fruit vegetables and root or stem vegetables.