Factors Affecting Nitrite Content In Sauerkraut Of Ordos And The Control Measures

Sauerkraut is a kind of fermented vegetables,with a unique taste and flavors,nutrition,and health effect.However,sauerkraut with the problem of excessive nitrite.If excessive intaked,it can cause a variety kind of cancers.In this experiment,sauerkraut of Ordos were selected as the test object to determine the content of nitrite.At the same time,the fermentation processes of the sauerkraut were also optimized.Thereby,common spicy condiments and vitamin C were added to sauerkraut to study the inhibit ability to nitrite.The research results are as follows:(1)The average value of the nitrite content in the 45 obtained sauerkraut samples was 20.90±0.04 mg/kg,which was higher than GB 2762,which limit of 20 mg/kg.The highest content is 26.71 ±0.03mg/kg,the lowest content is 15.95±0.07mg/kg;27 samples exceed the standard,accounting for 60.0%.(2)Nitrite content in sauerkraut was selected as the index to optimize the fermentation conditions:the best fermentation strain was lactic acid bacteria(Lactobacillus acidophilus:Lactobacillus plantarum:Lactobacillus rhamnosus?1:1:1)On this basis,the salt concentration,initial pH,fermentation time,fermentation temperature were carry out to a significant impact and L9(34)orthogonal experiment.The final optimal fermentation conditions were:inoculation amount of lactic acid bacteria 1.5g/500g,fermentation time 26 days,salt concentration 9.0%,fermentation temperature 25?,and initial pH6.0.Under this condition,the nitrite content in sauerkraut was 5.12 mg/kg,which was 17.6%lower than optimization(6.21 mg/kg)before.(3)On the basis of optimal fermentation conditions,onion,ginger,garlic,vitamin C and tea polyphenols were added to inhibit the nitrite.On the basis of the optimal addition amount of onion,ginger,garlic,vitamin C and tea polyphenols,by dividing the optimal addition amount of onion,ginger and garlic with vitamin C and tea respectively The phenol is compounded in a 1:1 ratio.The results showed that,the combined addition had a stronger inhibitory effect on the nitrite content.The combination of garlic and vitamin C and the combination of garlic and tea polyphenols showed better effects on nitrite than the other two combinations.Which output was 2.81 mg/kg and 1.72 mg/kg respectively.It proves that the addition of seasoning and antioxidant have a better inhibition on the nitrite.