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Ricotta fresca cheese is the product of Sardinian dairy industry most exposed to microbial post-process contamination. Due to its technological characteristics, intrinsic parameters, pH (6.10-6.80) and water activity (0.974-0.991), it represents an excellent substrate for the growth of spoilage and pathogenic microorganisms, which are usually resident in cheese-making plants environments. Generally, ricotta fresca has a shelf life of 5-7 days. For this reason, at industrial level, modified atmosphere packaging (MAP) is used to extend the durability of the product. However, few investigations have been conducted to validate the use of MAP in ricotta fresca. The aim of this work is to evaluate the shelf life of ricotta fresca under MAP. A total of 108 samples were collected from three Sardinian industrial cheese-making plants and analysed within 24 h after packaging and after 7, 14 and 21 days of refrigerated storage. Aerobic mesophilic bacteria, mesophilic and thermophilic cocci and lactobacilli, Enterobacteriaceae and E. coli, L. monocytogenes, Pseudomonas spp, Bacillus cereus, yeasts and moulds, and the chemical-physical parameters and composition of the product were determined. At the end of the shelf life, Pseudomonas spp. and Enterobacteriaceae reached high concentrations, 5 to 7 and 3 to 6 log10 colony forming unit g–1, respectively. The presence of environmental contaminants indicates that the use of MAP without the appropriate implementation of prerequisite programmes is not sufficient to extend the durability of ricotta fresca. Gas mixture and packaging material should be selected only on the basis of scientific evidence of their effectiveness.

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Anisakiasis is a gastrointestinal fish-borne zoonosis caused by the ingestion of third stage larvae of the genus Anisakis. Between January and December 2013, 1112 specimens of four commercial fish species (Engraulis encrasicolus, Merluccius merluccius, Scomber colias and Trachurus mediterraneus) marketed in Sardinia (Italy) were examined for Anisakis sp. The overall prevalence of Anisakis spp larvae was 39.9%, all morphologically identified as Type I. Scomber colias showed the highest prevalence (100%), followed by M. merluccius (Atlantic 91.0%, Mediterranean 71.2%), T. mediterraneus (32.7%) and E. encrasicolus (25.9%). All the larvae found in Mediterranean hosts were genetically identified as Anisakis pegreffii, whereas 90.0% of the larvae found in the Atlantic M. merluccius belonged to Anisakis simplex sensu stricto and 10.0% to A. pegreffii. The mean abundance of Anisakis sp. larvae was positively correlated with fish size in E. encrasicolus, Atlantic M. merluccius and local M. merluccius. The prevalence of infection was greater in the body cavity (37.9%) than in the edible muscle (9.4%). However, 1.8% of the examined fish were infected exclusively in the muscle. Therefore, the risk associated to the consumption of raw or undercooked fishery products poses the need of measures such as visual inspection and preventive treatments to guarantee consumers’ health.