Sausage fermentation and starter cultures in the era of molecular biology methods

Abstract

Fermented sausages have a long tradition originating from Europe and they constitute a significant part of the Mediterranean diet. This kind of products has a specific microbiota that is typical of the region or area where they are produced. Therefore, in order to protect the traditional aspect of these products, it is essential to understand the microbial ecology during fermentation by studying the dynamic changes that occur and to select autochthonous starter cultures that can be used in the production. In this paper we summarize the state of the art concerning the selection and use of starter cultures and ecology aspects of naturally fermented sausages. We pay particular attention to the application of bacteriocinogenic strains as they could provide an additional tool in the prevention of foodborne pathogens as well as enhancing the competitiveness of the starter organisms. Microbial ecology of fermented sausages has been determined by traditional microbiological methods, but the introduction in food microbiology of new molecular techniques complements the studies carried out so far and allows scientists to overcome the limitations of traditional methods. Next Generation Sequencing (NGS) techniques represent a change in the way microbiologists address ecology and diversity in foods. Indeed the application of metataxonomics and metagenomics will permit a detailed understanding of microbial ecology. A thorough knowledge of the mechanisms behind the biological processes will enhance meat fermentation control and modulation to obtain products with desired organoleptic properties.

Antilisterial Effect and Influence on Listeria monocytogenes Gene Expression of Enterocin or Enterococcus faecalis in Sliced Dry-Cured Ham Stored at 7°C

“…The use of bacteriocinogenic cultures has been largely explored for fermented foods, including fermented meat products. In the case of fermented meat products, the bacteriocin producing strains used act as starter culture and contribute to the safety, by microbial competition, bacteriocin and lactic acid production and to the development of the desired organoleptic properties of the final product (7). In non-fermented meat products, bacteriocin producing lactic acid bacteria may be added as protective cultures and they are not expected to grow significantly or to produce large amounts of lactic acid.…”

Lactic Acid Bacteria: Variability Due to Different Pork Breeds, Breeding Systems and Fermented Sausage Production Technology

“…High-throughput sequencing (HTS) techniques represent a relatively new approach in the way microbiologists address ecology and diversity in different environments, and consequently also in foods. As explained by Franciosa et al [25], in HTS, mixed nucleic acid molecules from a complex ecosystem can be sequenced, and therefore can lead to a detailed profile of the microbial populations (identified as operational taxonomic units, OTU) present. In the mid-2000s, HTS technologies became ubiquitous in microbial ecology studies, but limitations remain: a) DNA is a chemically stable molecule, which can be found for a long time after the death of a cell; b) quantification of the genera and/or species is only relatively possible.…”

Effects of Lactobacillus plantarum Bacteriocinogenic Culture on Physicochemical, Microbiological, and Sensorial Characteristics of “Chouriço Vinha d´Alhos”, a Traditional Portuguese Sausage

“…Actually, Vaz Velho et al (2013) used a higher initial concentration (9 log CFU/g) and, after 7 days, inoculated Listeria had decreased 2 log cycles. Alternatively, "Chouriço de Vinha d'Alhos" could have some endogenous bacteriocinogenic lactic acid bacteria, which may act in the same way as inoculated bacteriocinogenic lactic acid bacteria (Franciosa et al, 2018).…”