Microbiological and physicochemical profile of traditionalSalsicda toscanaduring storage

Abstract

The aim of this study was to evaluate the evolution during refrigerated storage of the main microbiological and physicochemical parameters of a traditional Italian fresh sausage, salsiccia toscana. The following parameters were analyzed at Days 0, 6 and 9 of storage: total aerobic mesophilic and psychrotrophic counts, Brochothrix thermosphacta, lactic acid bacteria, Pseudomonadaceae, Enterobacteriaceae, Escherichia coli, Micrococcaceae, yeasts and moulds, Salmonella spp., Listeria monocytogenes; pH, Aw, moisture, protein, total lipids, ash, fatty acid composition, Thiobarbituric Acid Reactive Substances, colour measurement. The results revealed a statistically significant increase in the main microbiological parameters between Days 0 and 9 of refrigerated storage, with total bacterial counts exceeding 10 7 CFU/g after nine days and Brochothrix thermosphacta representing the main spoilage microorganism. Among physicochemical parameters, discolouration was noted during the time of storage, with a significantly paler colour on the surface of sausages with casings after nine days of storage. Considering that the initial bacterial counts were higher than 10 5 CFU/g for Brochothrix thermosphacta, Pseudomonadaceae, lactic acid bacteria and Enterobacteriaceae, and that the product is traditionally purchased loose without any packaging, it is fundamental to improve the good manufacturing practices, particularly measures to control processing temperatures.

Effect of a Lactobacillus sakei and Staphylococcus xylosus protective culture on Listeria monocytogenes growth and quality traits of Italian fresh sausage (salsiccia) stored at abusive temperature

“…External and internal mean colour parameters at different sampling times (t0, t3, t7 and t9, days) of experimental sausages, with (PCþ) and without (PC-) protective culture, stored at 7 C. TPC counts. These data are in agreement with those of Tremonte et al (2005), and lower than those reported by other authors (Kamdem et al 2007;Chiavaro et al 2008;Nuvoloni et al 2012) for Italian fresh sausages. Regardless of the good initial hygiene, PC-sausages reached at the end of the shelf life (t7) a TMC of almost 7 log CFU/g at abusive temperature.…”

“…Regardless of the good initial hygiene, PC-sausages reached at the end of the shelf life (t7) a TMC of almost 7 log CFU/g at abusive temperature. Indeed, total viable aerobic counts higher than 6 log CFU/g are usually reported for Italian fresh sausage after 7 days of storage (Tremonte et al 2005;Kamdem et al 2007;Chiavaro et al 2008;Nuvoloni et al 2012).…”

“…Regarding colour evolution, and particularly a à values evolution, these were significantly lower in PC þ samples starting at t7 on the external surface and at t9 for internal surface. Colour changes, and particularly red discolouration, are physiological at the end of the shelf-life of sausages (Chiavaro et al 2008;Nuvoloni et al 2012). The more pronounced discolouration of PC þ samples, particularly on the external surface, could be related to the simultaneous production of organic acids and hydrogen peroxide by L. sakei.…”

Bacterial community of industrial raw sausage packaged in modified atmosphere throughout the shelf life

“…Similar results were obtained by Cocolin et al (2004) in fresh sausages for mesophilic aerobic counts, lactic acid bacteria, staphylococci, and enterobacteria. Higher initial contamination of analogous products was found in previous studies (Torrieri et al, 2011;Nuvoloni et al, 2012). In contrast, lower concentrations of these microbial groups were observed when antimicrobials were used both in carcasses cleaning and sausage manufacture (Benson et al, 2014).…”

Volatile profile of Conciato Romano cheese, a traditional Italian cheese, during ripening

“…Little is known about the volatile composition of some traditional cheeses during ripening considering the effect of external and inner parts, particularly for Conciato Romano cheese, where the body interacts with other components such as extra‐virgin olive oil, red wine, and aromatic herbs. No papers were found in literature about the aroma of this typical cheese and, only few studies were found about microbiological profile focused on bacterial evolution during aging . Delgado et al studied the volatile profile of a Spanish goat raw milk cheese called “Queso Ibores” at four stages of maturation (1, 30, 60, and 90 days) using solid‐phase micro‐extraction‐gas chromatography‐mass spectrometry (SPME‐GC/MS), but the study did not consider the changes during a longer aging period.…”