Evaluation of nitrate and nitrite contents in pickled fruit and vegetable products

Authors: DING, ZHANSHENG - Jiangnan University; Johanningsmeier, Suzanne; Price, Robert; Reynolds, Rong; Truong, Van Den; Conley Payton, Summer; Breidt, Frederick

Submitted to: Food Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/1/2018
Publication Date: 3/20/2018
Publication URL: http://handle.nal.usda.gov/10113/5919161
Citation: Ding, Z., Johanningsmeier, S.D., Price, R.E., Reynolds, R., Truong, V., Conley Payton, S.B., Breidt, F. 2018. Evaluation of nitrate and nitrite contents in pickled fruit and vegetable products. Food Control. 90:304-311. https://doi.org/10.1016/j.foodcont.2018.03.005.
DOI: https://doi.org/10.1016/j.foodcont.2018.03.005

Interpretive Summary: The influence of nitrate and nitrite in foods on human health has been controversial, with literature citing both positive and negative health effects. Our research was focused on measuring the concentration of these compounds in a wide variety of acidified vegetables (made by adding vinegar or other acids to fresh fruits and vegetables), as well as some fermented foods currently available in the US market. The naturally present antioxidants in foods may also be of interest when studying nitrite and nitrate levels due to reactive interactions between these compounds, so antioxidant levels were also measured. We found that nitrite was relatively rare in acidified vegetables, but was present in some of the fermented foods tested. Nitrate, on the other hand, was found to be present at varying levels in many acidified products. These results provide new information for evaluating nitrate and nitrite content in pickled fruit and vegetable products, and may be used to help assess the potential health consequences of these compounds in US consumer diets.

Technical Abstract: Our objective was to investigate nitrate and nitrite contents of acidified and fermented fruits and vegetables. L-ascorbic acid and total phenols were also examined based on the hypothesis that the presence of these antioxidant compounds may influence N-nitrosation reactions upon human consumption. The fermented and acidified vegetable products included 131 samples from multiple lots of 46 different commercially available products. Nitrite was detected in low concentrations (<1.5 mg/100 g) in four acidified (pickled green beans, red cabbage, pickled beets, and pickled mushrooms) and two fermented products (Greek olives and kimchi). Nitrate concentrations ranged from a mean value of 122 mg/100 g for kimchi to undetectable levels in acidified Brussels sprouts. Measures of antioxidant compounds showed that artichoke hearts had the highest total polyphenols (225 mg/100 g), and olive products had between 84 ± 5 mg/100 g (Spanish table olives) and 170 ± 8 mg/100 g (Greek olives). An acidified red pepper product had the highest L-ascorbic acid content of 32 ± 10 mg/100 g, with a low nitrate level of 0.1 ± 0.09 mg/100 g. These results provide new information for evaluating nitrate and nitrite contents in pickled fruit and vegetable products with regard to potential human dietary health consequences.