Determination of grated hard cheeses adulteration by near infrared spectroscopy (NIR) and multivariate analysis

Abstract

Cheese is a dairy product of massive consumption and is commonly commercialised as grated cheese. Adulteration of cheese reduces its quality and consequently, decreases its nutritional value. This work proposes an analytical tool to determine the adulteration of cheeses with higher levels of additives than those permitted (cellulose and silicon dioxide) and non-authentic substances used to increase weight and volume such as wheat-flour, wheat-semolina and sawdust. The proposed methodology is based on near infrared spectroscopy (NIR) and multivariate classification analysis. Excellent classification results were obtained with partial least squares discriminant analysis (PLS-DA) as adulterated samples were discriminated from original (unadulterated) samples. The prediction ability was assessed with adulterated commercial grated cheeses. The screening tool represents a fast, reliable and affordable way to perform quality control of grated cheeses to avoid consumer deception based on nutritional detriment and misleading labelling.