Classification of the geographical origin of Italian donkey milk based on differences in inorganic anions

Giuseppa Di Bella (1) , Vincenzo Lo Turco (1) , Angela Giorgia Potortì (2) , Rosario Rocco Luppino (1) , Vincenzo Fotia (1) , Francesca Conte (3) , Giacomo Dugo (1)

1 Department of Food and Environment Sciences
2 Experimental Zooprophylactic Institute of Sicily
3 Department of Veterinary Health Public

In this work the content of chlorides, nitrites, nitrates, phosphates and sulphates were used to classify 45 donkey milk samples collected from different Italian regions. An ion exchange chromatography with conductivity detector and chemical suppression method was used. The quantitative results indicate phosphates (569.39-1304.40 mg kg-1) and chlorides (545.93-1757.89 mg kg-1) that as the most abundant anions, followed by and sulphates (109.52-200.69 mg kg-1). The concentrations of nitrites and nitrates are found to be lower at 5.60 mg kg-1 and 5.50 mg kg-1.The data set was subdivided into three groups according to the region of origin of milk, was statistically evaluated by analysis of variance (ANOVA). Chlorides and nitrates concentrations showed a significant difference among farms (p<0.001). In a first discriminant analysis procedure, functions based on linear combinations of the loge-transformed element concentrations of anions were generated to classify donkey milk samples from different regions. In an alternative approach, a three-step discriminant analysis procedure to classify a milk sample was tested. The obtained results lead to a correct classification of donkey milk samples based on their anions content so that 91.1 through 97.8% of the samples were correctly classified. The procedure proved to be very simple so it could be used as an evaluation method for traceability of donkey milk thus preserving this peculiar product against frauds or commercial disputes.

Mots clés: Life Sciences

Giuseppa Di Bella, Vincenzo Lo Turco, Angela Giorgia Potortì, Rosario Rocco Luppino, Vincenzo Fotia, et al.. Classification of the geographical origin of Italian donkey milk based on differences in inorganic anions. Food Additives and Contaminants, 2012, pp.1. ⟨10.1080/19440049.2012.674979⟩. ⟨hal-00812882⟩