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

Abstract

Ten lots of industrial raw sausages in modified atmosphere (CO 30%, O 70%), produced in the same plant over 7 months, were analyzed at the day after production (S samples) and at the end of shelf life (E samples), after 12 days storage at 7 °C to simulate thermal abuse. Quality of the products was generally compromised by storage at 7 °C, with only 3 E samples without alterations. During the shelf life, the pH decreased for the accumulation of acetic and lactic acids. A few biogenic amines accumulated, remaining below acceptable limits. The profile of volatile compounds got enriched with alcohols, ketones, and acids (e.g. ethanol, 2,3-butanediol, 2,3-butandione, butanoic acid) originated by bacterial metabolism. Throughout the shelf life, aerobic bacteria increased from 4.7 log to 6.6 log cfu/g, and lactic acid bacteria (LAB) from 3.7 to 8.1 log cfu/g. Staphylococci, enterobacteria, and pseudomonads passed from 3.7, 3.0, and 1.7 to 5.5, 4.8, and 3.0 log cfu/g, respectively. Dominant cultivable LAB, genotyped by RAPD-PCR, belonged to the species Lactobacillus curvatus/graminis and Lactobacillus sakei, with lower amounts of Leuconostoc carnosum and Leuconostoc mesenteroides. Brochothrix thermosphacta was the prevailing species among aerobic bacteria. The same biotypes ascribed to several different species where often found in E samples of diverse batches, suggesting a recurrent contamination from the plant of production. Profiling of 16S rRNA gene evidenced that microbiota of S samples clustered in two main groups where either Firmicutes or Bacteroidetes prevailed, albeit with taxa generally associated to the gastro-intestinal tract of mammals. The microbial diversity was lower in E samples than in S ones. Even though a common profile could not be identified, most E samples clustered together and were dominated by Firmicutes, with Lactobacillaceae and Listeriaceae as the most abundant families (mostly ascribed to Lactobacillus and Brochothrix, respectively). In a sole E sample Proteobacteria (especially Serratia) was the major phylum.

Microbial Growth and Biogenic Amine Production in a Balkan-Style Fresh Sausage during Refrigerated Storage under a CO2-Containing Anaerobic Atmosphere: Effect of the Addition of Zataria multiflora Essential Oil and Hops Extract

“…The shelf-life of fresh sausages refrigerator-stored under anaerobiosis depends on the hygienic quality of raw materials, pH, a w , storage temperature, atmosphere, etc. [4]. Some authors, based on the appearance of off-odors and discoloration, have found a shelf-life for these sausages slightly longer than 10 days [3] and others of more than 20 days [5][6][7].…”

“…During refrigerated storage of fresh sausages under vacuum or anaerobic MAP, and most probably due to the growth of LAB and Enterobacteriaceae, a significant production of biogenic amines (BA) such as tyramine, putrescine, and cadaverine occurs [4,8]. In a previous study [2], levels of tyramine higher than 100 mg/kg were found in a Mexican fresh sausage stored in anaerobic MAP for more than two weeks, which represents a health risk and corroborates the need to control the production of BA in fresh sausages.…”

Modeling the Growth and Interaction Between Brochothrix thermosphacta, Pseudomonas spp., and Leuconostoc gelidum in Minced Pork Samples

“…predominant strains (>50% reads) from different batches of Belgian MP samples at the end of their use-by-date (Cauchie et al, 2019). Considered as the main representative spoilage species in meat and meat products (Koort et al, 2005;Liu et al, 2006;Nychas et al, 2008;Pennacchia et al, 2009Pennacchia et al, , 2011Andritsos et al, 2012;De Filippis et al, 2013;Casaburi et al, 2014;Stoops et al, 2015;Zhao et al, 2015;Mann et al, 2016;Stellato et al, 2016;Del Blanco et al, 2017;Geeraerts et al, 2017;Raimondi et al, 2018;Li et al, 2019;Mansur et al, 2019;Peruzy et al, 2019), these bacteria were inoculated on irradiated MP samples, in mono-and in co-culture experiments.…”

Assessment of Spoilage Bacterial Communities in Food Wrap and Modified Atmospheres-Packed Minced Pork Meat Samples by 16S rDNA Metagenetic Analysis

“…The introduction of molecular methods, especially culture-independent approaches, have contributed to the exploration of various food microbiota (Galimberti et al, 2015;Pinu, 2016;Garofalo et al, 2017;Parlapani et al, 2018), as for beverages (Elizaquivel et al, 2015), vegetables Gu et al, 2018;Liu et al, 2019), and for dairy (Nalbantoglu et al, 2014;Riquelme et al, 2015;Ceugniez et al, 2017;Porcellato et al, 2018), seafood Parlapani et al, 2018;Silbande et al, 2018), and meat products (Cocolin et al, 2004;Pennacchia et al, 2011;Nieminen et al, 2012;Benson et al, 2014;Greppi et al, 2015;Polka et al, 2015;Stoops et al, 2015;Zhao et al, 2015;Delhalle et al, 2016;Mann et al, 2016;Carrizosa et al, 2017;Cauchie et al, 2017;Kaur et al, 2017;Korsak et al, 2017;Peruzy et al, 2019;Vester Lauritsen et al, 2019), in order to assess the microbial levels and diversity of food and food products Pothakos et al, 2014;Lee et al, 2017;Rouger et al, 2018). The interest of this method to characterize the dominant spoilage bacteria in pork meat and meat products was also described (Andritsos et al, 2012;Mann et al, 2016;Raimondi et al, 2018;Peruzy et al, 2019).…”