Traditional Fermented Meat Products Research Articles

What is the Main Processing Factor Influencing Staphylococcus Species Diversity in Different Manufacturing Units?

The microbiota of traditional dry-cured sausages and industrial environment was assessed to characterize the diversity of coagulase-negative staphylococci (CNS), and establish potential relationships with hygiene level or technological characteristics. Eight processing units from South Portugal were audited according to a checklist of requirements. Environmental and products' samples at different production stages were evaluated regarding hygiene and safety criteria. CNS were recovered, characterized, and their potential use as starters evaluated. Low genetic diversity was observed for Staphylococcus xylosus, whereas Staphylococcus equorum showed diverse genetic profiles. Staphylococcus xylosus predominated in products with a long period of cold smoking, Staphylococcus saprophyticus in products with a long period of hot smoking, Staphylococcus epidermidis in products with a short period of cold smoking, and S. equorum in nonsmoked products. Most S. xylosus were resistant to tetracycline, whereas S. equorum were susceptible. Antibioresistance restricted the selection of starters due to safety recommendations. PRACTICAL APPLICATION: The present manuscript highlighted a few staphylococci strains that could potentially be used as starter cultures in fermented meat products. These selected strains do not show resistance to antimicrobials, exhibit adequate technological features, and are well adapted to the industrial environments of meat processing industries using different processing technologies. Therefore, the selected strains ready to be used in the manufacturing of traditional fermented meat products to ensure safety, standardize product properties, and shorten ripening.

Relationships between bacterial community and metabolites of sour meat at different temperature during the fermentation

This study was designed to explore the temperature effects on bacterial communities and metabolites, as well as their relationships during the fermentation of sour meat, a traditional fermented meat product in the ethnic minority regions of China. Results showed that reduction of pH and increase of lactic acid and free amino acid contents occurred (p < 0.05) as the fermentation temperature and time increased, and the tendency was more apparent at higher temperature. During the fermentation, Lactobacillus gradually replaced other genera, and higher the temperature, more rapid was the process. Both the number and amount of volatile organic compounds increased at higher temperatures. Hexanal, benzaldehyde, nonanal, (E,E)-2,4-decadienal, 1-octen-3-ol and octanal were identified as the key volatile organic compounds produced by Lactobacillus in sour meat as main contributors to odor as confirmed by variable importance in the projection analysis. Redundancy analysis and Pearson correlation showed positive correlation between Lactobacillus and desired product characteristics, such as higher content of lactic acid, free amino acids, volatile organic compounds, and lower pH and water activity values, which may represent a better quality and longer shelf life after fermentation at higher temperature. Therefore fermentation at 20 °C and 25 °C are proposed as optimum temperatures for sour meat production.

Effects of temperature on microbial succession and quality of sour meat during fermentation

Little is known about the relationship between physicochemical characteristics and bacterial community of sour meat, a traditional fermented meat product in China. In this study, temperature effects on bacterial community and quality of sour meats during fermentation were investigated. The results showed the reduction of pH, TBARS, and water content was closely related to the increase in temperature. Microbial succession, in which the dominant microorganism species found in the microbial community changes, was observed during the fermentation process of sour meat. The dominant species found in the early stages of fermentation was Lactobacillus sakei whereas the dominant species was Lactobacillus curvatus during the middle stage and Lactobacillus plantarum during the later stage. Higher temperatures were found to be related to the shift of water populations T2 (including T2b1, T2b2, T21, and T22) toward faster relaxation times. Rapid fermentation and better quality were obtained at higher fermentation temperatures (particularly at 25 °C), which might be due to increased inhibition of Enterobacteriaceae and Pseudomonas growth as well as tougher texture. Redundancy analysis (RDA) showed a close relationship between L. plantarum and desired product characteristics, which indicated that L. plantarum could be regarded as an indicator of fermentation maturation and product quality.

Evaluating the impact of vegetal and microalgae protein sources on proximate composition, amino acid profile, and physicochemical properties of fermented Spanish “chorizo” sausages

The aim of this work was to evaluate the impact of the addition of vegetable (beans, lentils, and broad beans) and algae (Chlorella and Spirulina) protein sources on physicochemical and nutritional properties of fermented Spanish “chorizo” sausages. Color, pH, texture parameters, protein, amino acid profile, and the content of carbohydrates were significantly different among the batches. Protein content was significantly higher in the sausages with protein from soy (35.62%), Chlorella (34.66%), Spirulina (34.89%), and broad beans (34.66%) compared to the samples enriched with protein from bean and lentil, being lysine (≈19%), arginine (≈17.5%), and leucine (17.5%) the predominant essential amino acids, while glutamic acid (≈32%) and aspartic acid (≈19%) were the most abundant nonessential amino acids. It can be concluded that protein extracted from beans, lentils, broad beans, Chlorella, and Spirulina can be used to enrich “chorizo” as an alternative to soy protein. Practical applications Consumer´s growing awareness regarding the use of new healthy ingredients that could give an added value to meat products has led food industry to investigate alternative protein sources from vegetal and algae origin. “Chorizo” sausages are one of the traditional fermented meat products typical from Spain. During “chorizo” fermentation several changes on protein can occur, thus being of a paramount importance to evaluate its nutritional and quality changes. Enrichment of “chorizo” with protein from vegetal and algae origin can constitute a useful alternative to improve “chorizo” nutritional profile, and consequently increasing its market opportunity.

Role of autochthonous starter cultures in the reduction of biogenic amines in traditional meat products

The transformation of raw meat in highly appreciated traditional fermented meat products is a topic of great importance for researches and consumers. At first, we describe the importance and feelings about traditional food to local and foreign consumers. Then the role of autochthonous microflora in the reduction of biogenic amine accumulation without changes in the expected general quality of traditional meat products is discussed. Both in vitro and re-inoculation studies were included in this review.

Presence of Salmonella spp., Listeria monocytogenes, Escherichia coli O157 and Nitrate-Nitrite Residue Levels in Turkish Traditional Fermented Meat Products (Sucuk and Pastırma)

#nofulltext# --- Sakar, Fitnat Sule (Arel Author), Buyukunal, Serkan Kemal (Arel Author), Erginbas, Cinar (Arel Author) --- Conference: II International VETistanbul Group Congress. DIGEST : Saint-Petersburg, Russia, 07-09 April 2015

Characterization of regional Portuguese kitchens for alheiras de Vinhais (PGI) production with respect to the processing conditions, final product quality and legal framing

Alheira de Vinhais is a traditional fermented meat product, produced in the North of Portugal, generally in small units called regional kitchens. In the present study, the requisites established by the European and Portuguese normatives and how these are being applied in these kitchens are discussed. In addition, the evaluation of the hygienic, sanitary and environmental conditions in those establishments, as well as, the microbiological quality of the final product are reported.In order to characterize the processing units, a check-list was applied and microbiological analysis of environmental samples and alheiras were performed.The present work allowed verifying that, despite of some shortcomings, the basic hygiene and the overall processing conditions were appropriate for small-scale production of alheiras. In fact, the structural and functional conditions of the regional kitchens that were assessed were found to be quite satisfactory and complied with the European and Portuguese normative. Even though there are exceptions in the European regulation for these kinds of products, Portugal has normative applicable to these products that are sufficient to guarantee the food quality and safety. In regards to the microbiological environment air quality, unsatisfactory food processing hygienic conditions were sometimes observed. Microorganisms, such as yeasts/molds, coliforms and E. coli, indicative of poor hygiene practices were only found four times on surfaces and equipment. Most of the time, the food handlers had clean hands. Microorganisms associated with foodborne illnesses, such as Salmonella spp., S. aureus and Listeria spp. were not detected in any sample. Thus, the results obtained showed that the production of this kind of products must be promoted, since good hygiene and manufacturing practices are followed.

Virulence factors among enterococci isolated from traditional fermented meat products produced in the North of Portugal

The aim of this work was to characterize Enterococcus spp. isolated from Alheira, Chouriça de Vinhais and Salpicão de Vinhais, fermented meat products produced in the North of Portugal, concerning their potential pathogenicity. One hundred and eighty two isolates (76 identified as Enterococcus faecalis, 44 as Enterococcus faecium, 1 as Enterococcus casseliflavus and 61 as Enterococcus spp.) were studied. Twenty six percent of isolates were gelatinase producers. None of the isolates produced lipase nor DNase activities. Hemolytic activity using sheep and human blood from two types (A and O) was assessed. One isolate was β-hemolytic in human blood. Results obtained in sheep blood were quite different from those obtained in human blood. Biofilm production in batch and in fed-batch mode was evaluated. In batch mode, only 28.0% and 3.9% of isolates were classified as moderate and strong biofilm producers, respectively, and in fed-batch mode, 35.7% and 63.2% of isolates were classified as moderate and strong biofilm producers, respectively. The presence of 13 virulence genes ( efaAfs, efaAfm, esp, agg, cylM, cylB, cylA, cylL L cylL s and gelE) were investigated by PCR. The majority of enterococcal isolates showed the presence of one or more virulence factors, the most frequent genotype being efaAfs + gelE + agg + (41.5%). E. faecalis isolates harbored multiple virulence traits, while E. faecium isolates were generally free of virulence determinants. Phenotypic and genotypic evidence of potential virulence factors were identified in Enterococcus spp. isolates, which is a reason of concern.

Antibiotic susceptibility of enterococci isolated from traditional fermented meat products

Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chouriça de Vinhais and Salpicão de Vinhais, fermented meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

Biofilm development by Enterococcus spp. isolated from traditional fermented meat products and potential correlations with some virulence factors

Biofilm development by Enterococcus spp. isolated from traditional fermented meat products and potential correlations with some virulence factors

Microbial ecosystems of traditional fermented meat products: The importance of indigenous starters

This paper reviews the diversity of microbiota, both in the environment and in traditional fermented European sausages. The environments of processing units were colonised at variable levels by resident spoilage and technological microbiota, with sporadic contamination by pathogenic microbiota. Several critical points were identified such as the machines, the tables and the knives – knowledge crucial for the improvement of cleaning and disinfecting practices. Traditionally fermented sausages generally did not present a sanitary risk. The great diversity of lactic acid bacteria and staphylococci was linked to manufacturing practices. Development of indigenous starters is very promising because it enables sausages to be produced with both high sanitary and sensory qualities. Our increasing knowledge of the genomes of technological bacteria will allow a better understanding of their physiology in sausages.