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The extensive use of antibiotics as growth promoters, or their continued abusive misuse to cure or prevent the onset of bacterial infections as occurs in the intensive farming, may have played a pivotal role in the spread of reservoirs of antibiotic resistance (AR) among food-associated bacteria including pathogens representing risks to human health. The present study compares the incidence of tetracycline and erythromycin resistances in lactic acid bacteria (LAB) and coagulase negative staphylococci (CNS) from fermented products manufacturing using meat from intensive animal husbandry (industrialized manufacturing Italian salami) and from extensive farms (artisanal sausages facilities pork and llama Argentinean sausages). A higher incidence of tetracycline resistance (TET-R) compared to erythromycin resistance (ERY-R) was observed among the 205 isolates. Unlike CNS strains, the LAB showed a significant correlation between the TET-R and the ERY-R phenotypes. Genotypic assessment shows a high correlation with tetK and tetM for the TET-R strains and with ermB and ermC for the ERY-R strains. Multiple correspondence analyses have highlighted the association between AR phenotypes and CNS species isolated from Italian salami, while the susceptible phenotypes were associated with the LAB species from Argentinean sausages. Since antibiotic resistance in meat-associated bacteria is a very complex phenomenon, the assessment of bacterial resistance in different environmental contexts with diverse farming practices and food production technologies will help in monitoring the factors influencing AR emergence and spread in animal production.

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Microbiological, physicochemical and sensory characteristics of most popular Argentinean fermented sausages were evaluated in order to detect drivers of consumer liking. As a first step, a detailed description of instrumental parameters and consumer liking for fermented sausages was carried out. Furthermore, two multivariate mappings were performed: (1) cluster analysis to identify accepted fermented sausages based on overall acceptance and liking of appearance, aroma, taste and texture and (2) standard discriminant analysis to graphically recognize instrumental parameters that better described acceptance clusters. From these results, three fermented sausages groups with different acceptance patterns were segmented; taste and texture emerged as key sensory parameters and water activity, lightness, total protein, molds and enterococci among the physicochemical and microbiological variables were correlated with consumer liking. Practical Applications Getting insight into the factors involved in the consumer liking is a relevant task for food scientists who want to establish official standards in terms of sensory quality. From the results obtained herein, instrumental parameters linked to consumer acceptance can be proposed as quality criteria. These guidelines could be profited by manufacturers and technologists to improve fermented sausage production.

Llama sausage is still produced following artisanal procedures, with the autochthonous microbiota being mainly responsible for the fermentation process. In this work, the taxonomical identification and technological-safety criteria of coagulase-negative staphylococci (CNS) isolated from two different productions of llama sausages (P: pilot and A: artisanal) were investigated. Staphylococcus (S) equorum and S. saprophyticus were the species most frequently found in P production, followed by S. succinis and S. warneri; a wider species variability was observed in A factory being S. equorum, S. capitis, S. xylosus, S. pasteuri, S. epidermidis and S. saprophyticus as the main identified species. The technological characterization of 28 CNS strains showed their ability to hydrolyze gelatin and tributyrin together with a relevant nitrate reductase activity. Phenotypic and genotypic approaches were conducted to investigate the main safety traits. Llama’s CNS strains exhibited weak decarboxylase and hemolytic activity and low biofilm production; additionally, no enterotoxin genes were detected. Correlation analysis between phenotypic and genotypic data showed low values for the biofilm parameters, while high correlation was observed for oxacillin, ampicillin, tetracycline and aminoglycosides resistance and their genetic determinants. Data obtained may contribute to broaden knowledge about the autochthonous strains of this poorly studied fermented product, thus helping to select an appropriate combination of potential starter cultures to improve llama sausage safety and quality.

a b s t r a c tThis study focuses on meat protein degradation by different starter cultures. Sausage models inoculated with Lactobacillus curvatus CRL705 and Staphylococcus vitulinus GV318 alone and as a mixture were incubated 10 days at 22 • C. Low molecular weight peptides (<3 kDa) derived from sarcoplasmic proteins were analyzed by a peptidomic approach. A diverse number of protein fragments were identified. The greatest peptides diversity was obtained when the mixed starter culture was present. Peptides mainly arose from myoglobin, creatine-kinase, glyceraldehyde-3-phosphate-dehydrogenase and fructose-biphosphate-aldolase (ALDOA).ALDOA hydrolysis was attributed to the mixed starter culture; the released peptides could act as biomarkers for a specific sausage technology.Significance: The selection of a specific autochthonous starter culture guarantees the hygiene and typicity of fermented sausages. The identification of new peptides as well as new target proteins by means of peptidomics represents a significant step toward the elucidation of the role of microorganisms in meat proteolysis. Moreover, these peptides may be further used as biomarkers capable to certify the use of the applied autochthonous starter culture described here.