Empleo de la espectroscopia VIS NIR para la identificación de trazas de cacahuete en productos alimentarios en polvo

Résumé

Certain populations show hypersensitivity to certain foods, and accidental ingestion triggers a response "shock" anaphylactic. This has forced food companies to conduct a comprehensive risk management of all their products. Peanuts are one of the most important allergens in the industry. NIR spectroscopy has recently been used to analyze the total amount of oil and fatty acids on intact peanut (Sudaram et al., 2012). The objective of this work is to study non-destructive methods that could be used by the food industries for detecting peanuts in powdered foodstuffs to supplement analytical techniques developed by the research group of the UCM TRADETBIO. All of this in the context of cooperation in the CEI Moncloa. The materials used were five peanut varieties under different treatments and geographical origin, provided by the Institute for Reference Materials EC, also milk powder, cocoa, wheat flour, and peanuts of different trademarks. For all of them were measured two series of spectra: near infrared NIR (896-1686 nm) and the ones provided with the hyperspectral camera HIS (400 -1000 nm). The results show that the VIS spectroscopy is sensitive to differences in the peanut as to its origin and / or treatment, since they induce changes in the color, being impractical the separation between blanched peanuts, milk and flour in this band spectral. The main differences between peanuts and other food ingredients have been found in the NIR range, specifically in the wavelength (1207-1210 nm), which are associated with a region of absorption of lipids. Infrared allows 100% of segregation of any type of peanut compared to other food ingredients. NIR spectroscopy combined with imaging techniques (hyperspectral or multispectral) could therefore be applied to detect traces of peanuts in powdered food, not influencing its origin and / or treatment at it is capable of removing any peanut from the rest of the food. This method could be a screening technique for the high cost method PCR.