Physicochemical, microbiological, and sensory characterization of ‘Nduja, a typical sausage from Calabria, southern Italy

Physicochemical parameters, microbiota, and sensory profile of 13 samples of ‘Nduja, a typical sausage from Calabria, Southern Italy, were determined. The chemical composition is characterized by a wide variability, confirming the differences between the producers' recipes. A common feature is the presence of fibers and sugars due to the addition of pepper (about 25%). The presence of sugars in the ripened product confirms that the fermentations were incomplete, as evidenced by the low counts of lactic acid bacteria and coagulase negative cocci. No spoilage bacteria were found. It has been verified that the pepper limit microbial growth, lowering pH and Aw in the mixture, so that Nduja may be considered a meat preserve, not a fermented sausage. Total biogenic amines content was <200 mg/kg, mainly cadaverine, histamine, and tyramine. Finally, as regards the sensory aspect, a trained panel identified 12 specific descriptors. Practical applications: Although ‘Nduja is produced artisanally and in a circumscribed area, having followed the migratory flows of Calabrian people it is known and diffused worldwide. Despite this diffusion, however, studies of the chemical composition, the microbiological, and the sensory characteristics are poor. This study provides information about the chemical and microbiological composition of different samples of ‘Nduja. The safety aspects, due to the massive addition of peppers, have also been verified. These traits are useful for producers who must guarantee a safe product to consumers. This paper is the first to show the sensory aspects of ‘Nduja in detail, creating a specific sensory profile with proper descriptors. All this information could help in drafting a protocol for Community Protected Geographical Indication when required.