Fish meal analysis by near-infrared spectroscopy

Regarding animal nutrition, fish meal is a premium source of omega-3 fatty acids, protein, and essential minerals. Due to its nutritional properties, it is not only widely used in aquaculture, but also as an additive to swine feed and poultry feed. To analyze the main quality components of fish meal, such as fiber, fat, protein, moisture, and ash content, multiple wet chemistry methods are usually needed.

Instead of waiting hours for the results from these wet chemical techniques, near-infrared spectroscopy (NIRS) delivers results within seconds without the use of chemicals. This allows manufacturers to execute frequent checks against product specifications and perform fish meal quality control with ease.

The collected NIR spectra of fish meal samples (Figure 2) were used to create prediction models for the following parameters: protein, fat, moisture, ash, and fiber content. To validate the models, 25% of the data set was used to create an independent validation set. Correlation diagrams which display the relation between the NIR prediction and the lab values measured with standard methods are shown in Figures 3–8 together with the respective figures of merit (FOM). The standard errors displayed of cross validation (SECV) and standard errors of prediction (SEP) show the expected accuracy during routine analysis of fish meal in QC laboratories.

This Application Note shows the feasibility of using near-infrared spectroscopy for fish meal feed analysis. The main composition parameters of protein, fat, ash, fiber, and water content are determined in seconds without the use of chemicals. NIRS helps to save costs and improve lab safety when compared to standard wet chemistry methods. By using NIRS for efficient multiparameter analysis, quality control laboratories can save hours of time per sample measurement (Table 1), resulting in much higher sample throughput.