14 July 2020

Accommodate Lower-Level Nitrogen Samples in Food Materials with an Optimised Combustion Method

Low-Level Nitrogen Samples in Food Materials

Did you catch our recent article on Food Navigator? Nitrogen content in food materials is necessary to measure when determining the total protein content. This measurement of nitrogen content can be performed using a classical wet chemistry method, but this tends to be a slow and tedious process. The combustion-based Dumas method has gained popularity in recent years as it significantly increases laboratory productivity. Yet when the sample has a low level of nitrogen it can be challenging to analyse. Examples of these hard-to-analyse samples include dry corn starch, NDIN filter bags, nutritional drinks, and beer. How can the combustion method be optimised to accommodate these lower-level nitrogen samples?

Recently, our team investigated how to optimise the combustion-based methods in this Food Navigator article“One way is to increase the sample mass, therefore increasing the amount of nitrogen presented to the instrument for detection,” explained Mason Marsh, LECO's Organic Product Manager. “This can also be significantly helpful when analyzing samples that are heterogeneous in nature as well.” But does increasing the sample size affect the precision of the results?

In the article, the analysis process is summarised for our FP828, which is capable of analyzing samples under 1.0 gram and our FP928 which is designed for larger samples over 1.0 gram. A comparison of the data was made to indicate which instrument provided the best and most precise results. Read the article to see how these combustion methods were optimised for low-level nitrogen samples.