Nitrite in feed – Legal background, status of analytical methods and technological knowledge

Abstract

Feed materials in general and especially those from sugar industries are affected by recent European legislation setting maximum limits for nitrite contents in feed materials, which have not previously been subject to legal limits. Legal limits for undesirable substances require analytical methods to verify compliance. After reviewing analytical studies and historical data on nitrite contents in feed materials it became obvious, that molasses currently being produced in Europe would only comply with this limit in a few cases and that difficulties would arise from the lack of existing validated analytical methods for this purpose. This impedes also the monitoring of the status quo for studies about possible technological measures as demanded by European authorities. This publication describes in detail the legal background and nutritional consequences of limiting the nitrite content in feed. The analytical challenge of identifying and developing appropriate and reliable methods for detecting nitrite contents in the complex matrices of feed at that low level and that are suitable to be carried out in factory laboratories is outlined. Following a review of the knowledge on this subject, it was found that there are currently no studies, which deal with the import, formation, distribution and degradation of nitrite along the sugar manufacturing process. The task for the future is primarily to find and validate appropriate analytical methods which are essential for investigating the technological processes in the sugar industry in order to find measures to control the nitrite level in feed.