Evaluation of Nitrite in Ready-Made Soups

Erkekoglu P., Sipahi H., BAYDAR T.

FOOD ANALYTICAL METHODS, vol.2, no.1, pp.61-65, 2009 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 2 Issue: 1
  • Publication Date: 2009
  • Doi Number: 10.1007/s12161-008-9045-0
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.61-65
  • Keywords: Nitrite, Soup, Spectrophotometric Method, Food Contamination, Toxicity, FATAL METHEMOGLOBINEMIA, NITRATE, VEGETABLES, FRUIT
  • Hacettepe University Affiliated: Yes


As time is very important for today's people, ready-made soups in different forms (powder, liquid, canned) are consumed highly. Nitrite has been implicated with a variety of long-term adverse effects and has been of interest to public health providers and governmental regulators for the last 40 years. The present study was aimed to assess nitrite levels in commercially available soups in powder form by using a spectrophotometric method and to evaluate the possible toxicological outcomes. For this purpose, 66 ready-made soups were randomly collected and divided into seven groups: tomato-, chicken-, yoghurt-, mushroom-, lentil-, meat-, and vegetable-based. The minimum-maximum and median levels of nitrite content of the soup groups are 28-2,091 (median, 108), 53-400 (median, 136), 26-129 (median, 47), 58-197 (median, 109), 12-225 (median, 38), 12-555 (median, 40), 184-1229 (median, 389) mg kg(-1), respectively. Meat- and tomato-based soups have the highest nitrite contamination among the groups. On the other hand, acceptable daily intake (ADI) of nitrite given by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Scientific Committee on Food (SCF) is 0-0.07 mg kg(-1) (body weight, b.w.) per day, while Environmental Protection Agency (EPA) has set a reference dose (RfD) of 0.10 mg nitrite nitrogen per kilogram b.w. per day (equivalent to 0.33 mg nitrite ion per kilogram b.w. per day). This means that the highest intake of nitrite a 70-kg person must be no more than 4.9 mg in 1 day according to JECFA and SCF and 7 mg kg(-1) b.w. per day according to EPA. However, nitrite intake from one portion (13 g) meat-based soups, when calculated with median daily intake levels (5.05 mg), exceeds the limit of JECFA and SCF. With long-term daily consumption of high nitrite levels exceeding ADI, the risk of mild to moderate methemoglobinemia would be increased, especially for susceptible populations such as young children and elderly. Besides, the higher intake of nitrite from foodstuff and other sources may induce the formation of carcinogenic nitrosamines which are formed endogenously from nitrites and nitrates.