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Tsouggou N, Slavko A, Tsipidou O, Georgoulis A, Dimov SG, Yin J, Vorgias CE, Kapolos J, Papadelli M, Papadimitriou K. Investigation of the Microbiome of Industrial PDO Sfela Cheese and Its Artisanal Variants Using 16S rDNA Amplicon Sequencing and Shotgun Metagenomics. Foods 2024; 13:1023. [PMID: 38611328 PMCID: PMC11011710 DOI: 10.3390/foods13071023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 03/17/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
Sfela is a white brined Greek cheese of protected designation of origin (PDO) produced in the Peloponnese region from ovine, caprine milk, or a mixture of the two. Despite the PDO status of Sfela, very few studies have addressed its properties, including its microbiology. For this reason, we decided to investigate the microbiome of two PDO industrial Sfela cheese samples along with two non-PDO variants, namely Sfela touloumotiri and Xerosfeli. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), 16S rDNA amplicon sequencing and shotgun metagenomics analysis were used to identify the microbiome of these traditional cheeses. Cultured-based analysis showed that the most frequent species that could be isolated from Sfela cheese were Enterococcus faecium, Lactiplantibacillus plantarum, Levilactobacillus brevis, Pediococcus pentosaceus and Streptococcus thermophilus. Shotgun analysis suggested that in industrial Sfela 1, Str. thermophilus dominated, while industrial Sfela 2 contained high levels of Lactococcus lactis. The two artisanal samples, Sfela touloumotiri and Xerosfeli, were dominated by Tetragenococcus halophilus and Str. thermophilus, respectively. Debaryomyces hansenii was the only yeast species with abundance > 1% present exclusively in the Sfela touloumotiri sample. Identifying additional yeast species in the shotgun data was challenging, possibly due to their low abundance. Sfela cheese appears to contain a rather complex microbial ecosystem and thus needs to be further studied and understood. This might be crucial for improving and standardizing both its production and safety measures.
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Affiliation(s)
- Natalia Tsouggou
- Department of Food Science and Technology, University of the Peloponnese, 24100 Kalamata, Greece; (N.T.); (A.S.); (J.K.); (M.P.)
| | - Aleksandra Slavko
- Department of Food Science and Technology, University of the Peloponnese, 24100 Kalamata, Greece; (N.T.); (A.S.); (J.K.); (M.P.)
| | - Olympia Tsipidou
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, 18855 Athens, Greece;
| | - Anastasios Georgoulis
- Department of Biochemistry and Molecular Biology, National and Kapodistrian University of Athens, Panepistimioupolis-Zographou, 15784 Athens, Greece; (A.G.); (C.E.V.)
| | - Svetoslav G. Dimov
- Faculty of Biology, Sofia University “St. Kliment Ohridski”, 8, Dragan Tzankov Blvd., 1164 Sofia, Bulgaria;
| | - Jia Yin
- Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation, College of Life Sciences, Hunan Normal University, Changsha 410081, China;
- Hunan International Joint Laboratory of Animal Intestinal Ecology and Health, College of Life Science, Hunan Normal University, Changsha 410081, China
| | - Constantinos E. Vorgias
- Department of Biochemistry and Molecular Biology, National and Kapodistrian University of Athens, Panepistimioupolis-Zographou, 15784 Athens, Greece; (A.G.); (C.E.V.)
| | - John Kapolos
- Department of Food Science and Technology, University of the Peloponnese, 24100 Kalamata, Greece; (N.T.); (A.S.); (J.K.); (M.P.)
| | - Marina Papadelli
- Department of Food Science and Technology, University of the Peloponnese, 24100 Kalamata, Greece; (N.T.); (A.S.); (J.K.); (M.P.)
| | - Konstantinos Papadimitriou
- Laboratory of Food Quality Control and Hygiene, Department of Food Science and Human Nutrition, 18855 Athens, Greece;
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Daza-Prieto B, Raicevic N, Cabal A, Hyden P, Mösenbacher T, Ladstätter J, Richter S, Stöger A, Joao Cardoso M, Chakeri A, Hasenberger P, Stadlbauer S, Mach RL, Martinovic A, Ruppitsch W. Enterococcus montenegrensis sp. nov., isolated from artisanal Montenegrin dry sausage. Int J Syst Evol Microbiol 2024; 74. [PMID: 38240650 DOI: 10.1099/ijsem.0.006206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024] Open
Abstract
A novel, Gram-positive, facultative anaerobe, coccoid and non-motile bacterium, designated as CoE-012-22T was isolated from dried beef sausage (the original name in Montenegro is Govedji Kulen) manufactured in the municipality of Rozaje (Montenegro) in 2021. Cells of this strain were oxidase- and catalase-negative. Growth occurred at 4-50 °C, at pH 5.0-8.0 and with 0-6.5 % (w/v) NaCl in diverse growth media. MALDI-TOF analysis identified the strain as Enterococcus canintestini (log score 2). Phylogenetic analysis of the 16S rRNA gene and whole genome sequences assigned the strain to the genus Enterococcus. The closest relatives were E. canintestini DSM 21207T and E. dispar ATCC 51266T with 16S rRNA gene sequence pairwise similarities of 99.34 and 98.59 %, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between isolate CoE-012-22T and other enterococci species were below the thresholds for species delineation thresholds (95.0 % ANI; 70.0 % dDDH) with maximum identities of 84.13 % (ANIb), 86.43 % (ANIm) and 28.4 % (dDDH) to E. saigonensis JCM 31193T and 70.97 % (ANIb), 88.99 % (ANIm) and 32.4 % (dDDH) to E. malodoratus ATCC 43197T. Two unknown Enterococcus isolates, Enterococcus sp. MJM12 and Enterococcus SMC-9, showed identities of 99.87 and 99.94 % (16S rRNA), 98.57 and 98.65 % (ANIb), 98.93 and 99.02 % (ANIm), and 89.8 and 90.0 % (dDDH) to strain CoE-012-22T and can therefore be regarded as the same species. Based on the characterization results, strain CoE-012-22T was considered to represent a novel species, for which the name Enterococcus montenegrensis sp. nov. is proposed. The type strain is CoE-012-22T (=DSM 115843T=NCIMB 15468T).
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Affiliation(s)
- Beatriz Daza-Prieto
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area of Biochemical Technology, Technical University Vienna, Vienna, Austria
| | - Nadja Raicevic
- FoodHub - Centre of Excellence for Digitalisationof Microbial Food Safety Risk Assessment and Quality Parameters for Accurate Food Authenticity Certification, University of Donja Gorica, Podgorica, Montenegro
| | - Adriana Cabal
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Patrick Hyden
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Tobias Mösenbacher
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Johann Ladstätter
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Susanne Richter
- Institute of Veterinary Disease Control, Austrian Agency for Health and Food Safety, Mödling, Austria
| | - Anna Stöger
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Maria Joao Cardoso
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
- ECDC Fellowship Programme, Public Health Microbiology path (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
| | - Ali Chakeri
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
- Center for Public Health, Medical University Vienna, Vienna, Austria
| | - Petra Hasenberger
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Silke Stadlbauer
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
| | - Robert L Mach
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area of Biochemical Technology, Technical University Vienna, Vienna, Austria
| | - Aleksandra Martinovic
- FoodHub - Centre of Excellence for Digitalisationof Microbial Food Safety Risk Assessment and Quality Parameters for Accurate Food Authenticity Certification, University of Donja Gorica, Podgorica, Montenegro
| | - Werner Ruppitsch
- Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Vienna, Austria
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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3
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Sioziou E, Kakouri A, Bosnea L, Samelis J. Antilisterial activity of raw sheep milk from two native Epirus breeds: Culture-dependent identification, bacteriocin gene detection and primary safety evaluation of the antagonistic LAB biota. CURRENT RESEARCH IN MICROBIAL SCIENCES 2023; 6:100209. [PMID: 38116185 PMCID: PMC10727937 DOI: 10.1016/j.crmicr.2023.100209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023] Open
Abstract
Raw milk from native small ruminant breeds in Epirus, Greece, is a valuable natural source of autochthonous lactic acid bacteria (LAB) strains with superior biotechnological properties. In this study, two bulk milks (RM1, RM2) from two local sheep yards, intended for traditional Kefalotyri cheese production, were preselected for bacteriocin-like antilisterial activity by in vitro tests. Their antagonistic LAB biota was quantified followed by polyphasic (16S rRNA gene sequencing; IGS for Enterococcus; a multiplex-PCR for Leuconostoc) identification of 42 LAB (RM1/18; RM2/24) isolates further evaluated for bacteriocin encoding genes and primary safety traits. Representative isolates of the numerically dominant mesophilic LAB were Leuconostoc mesenteroides (10) in both RMs, Streptococcus parauberis (7) in RM2, and Lactococcus lactis (1) in RM1; the subdominant thermophilic LAB isolates were Enterococcus durans (8), E. faecium (6), E. faecalis (3), E. hirae (1), E. hermanniensis (1), Streptococcus lutetiensis (2), S. equinus (1) and S. gallolyticus (1). Based on their rpoB, araA, dsr and sorA profiles, six Ln. mesenteroides strains (8 isolates) were atypical lying between the subspecies mesenteroides and dextranicum, whereas two strains profiled with Ln. mesenteroides subsp. jonggajibkimchi that is first-time reported in Greek dairy food. Two RM1 E. faecium strain biotypes (3 isolates) showed strong, enterocin-mediated antilisterial activity due to entA/entB/entP possession. One E. durans from RM1 possessed entA and entP, while additional nine RM2 isolates of the E. faecium/durans group processed entA or entP singly. All showed direct (cell-associated) antilisterial activity only, as also both S. lutetiensis strains from RM2 did strongly. Desirably, no LAB isolate was β-hemolyrtic, or cytolysin-positive, or possessed vanA, vanB for vancomycin resistance, or agg, espA, hyl, and IS16 virulence genes. However, all three E. faecalis from RM2 possessed gelE and/or ace virulence genes. In conclusion, all Ln. mesenteroides strains, the two safe, enterocin A-B-P-producing E. faecium strains, and the two antilisterial S. lutetiensis strains should be validated further as potential costarter or adjunct cultures in Kefalotyri cheese. The prevalence of α-hemolytic pyogenic streptococci in raw milk, mainly S. parauberis in RM2, requires consideration in respect to subclinical mastitis in sheep and the farm hygiene overall.
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Affiliation(s)
- Eleni Sioziou
- Department of Dairy Research, Institute of Technology of Agricultural Products, Hellenic Agricultural Organization – DIMITRA, Ethnikis Antistaseos 3, Katsikas, Ioannina 45221, Greece
| | - Athanasia Kakouri
- Department of Dairy Research, Institute of Technology of Agricultural Products, Hellenic Agricultural Organization – DIMITRA, Ethnikis Antistaseos 3, Katsikas, Ioannina 45221, Greece
| | - Loulouda Bosnea
- Department of Dairy Research, Institute of Technology of Agricultural Products, Hellenic Agricultural Organization – DIMITRA, Ethnikis Antistaseos 3, Katsikas, Ioannina 45221, Greece
| | - John Samelis
- Department of Dairy Research, Institute of Technology of Agricultural Products, Hellenic Agricultural Organization – DIMITRA, Ethnikis Antistaseos 3, Katsikas, Ioannina 45221, Greece
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Silva LF, Sunakozawa TN, Monteiro DA, Casella T, Conti AC, Todorov SD, Barretto Penna AL. Potential of Cheese-Associated Lactic Acid Bacteria to Metabolize Citrate and Produce Organic Acids and Acetoin. Metabolites 2023; 13:1134. [PMID: 37999230 PMCID: PMC10673126 DOI: 10.3390/metabo13111134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 10/29/2023] [Accepted: 11/01/2023] [Indexed: 11/25/2023] Open
Abstract
Lactic acid bacteria (LAB) are pivotal in shaping the technological, sensory, and safety aspects of dairy products. The evaluation of proteolytic activity, citrate utilization, milk pH reduction, and the production of organic compounds, acetoin, and diacetyl by cheese associated LAB strains was carried out, followed by Principal Component Analysis (PCA). Citrate utilization was observed in all Leuconostoc (Le.) mesenteroides, Le. citreum, Lactococcus (Lc.) lactis, Lc. garvieae, and Limosilactobacillus (Lm.) fermentum strains, and in some Lacticaseibacillus (Lact.) casei strains. Most strains exhibited proteolytic activity, reduced pH, and generated organic compounds. Multivariate PCA revealed Le. mesenteroides as a prolific producer of acetic, lactic, formic, and pyruvic acids and acetoin at 30 °C. Enterococcus sp. was distinguished from Lact. casei based on acetic, formic, and pyruvic acid production, while Lact. casei primarily produced lactic acid at 37 °C. At 42 °C, Lactobacillus (L.) helveticus and some L. delbrueckii subsp. bulgaricus strains excelled in acetoin production, whereas L. delbrueckii subsp. bulgaricus and Streptococcus (S.) thermophilus strains primarily produced lactic acid. Lm. fermentum stood out with its production of acetic, formic, and pyruvic acids. Overall, cheese-associated LAB strains exhibited diverse metabolic capabilities which contribute to desirable aroma, flavor, and safety of dairy products.
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Affiliation(s)
- Luana Faria Silva
- Institute of Biosciences, Humanities and Exact Sciences, Food Engineering and Technology Department, UNESP—São Paulo State University, São José do Rio Preto 15054-000, SP, Brazil; (L.F.S.); (T.N.S.); (D.A.M.); (A.C.C.)
| | - Tássila Nakata Sunakozawa
- Institute of Biosciences, Humanities and Exact Sciences, Food Engineering and Technology Department, UNESP—São Paulo State University, São José do Rio Preto 15054-000, SP, Brazil; (L.F.S.); (T.N.S.); (D.A.M.); (A.C.C.)
| | - Diego Alves Monteiro
- Institute of Biosciences, Humanities and Exact Sciences, Food Engineering and Technology Department, UNESP—São Paulo State University, São José do Rio Preto 15054-000, SP, Brazil; (L.F.S.); (T.N.S.); (D.A.M.); (A.C.C.)
| | - Tiago Casella
- Department of Dermatological, Infectious and Parasitic Diseases, FAMERP—São José do Rio Preto Medical School, São José do Rio Preto 15090-000, SP, Brazil;
| | - Ana Carolina Conti
- Institute of Biosciences, Humanities and Exact Sciences, Food Engineering and Technology Department, UNESP—São Paulo State University, São José do Rio Preto 15054-000, SP, Brazil; (L.F.S.); (T.N.S.); (D.A.M.); (A.C.C.)
| | - Svetoslav Dimitrov Todorov
- ProBacLab, Department of Food Science and Experimental Nutrition, Faculty of Pharmaceutical Sciences, USP—São Paulo University, São Paulo 05508-000, SP, Brazil;
- CISAS—Center for Research and Development in Agrifood Systems and Sustainability, Escola Superior de Tecnologia e Gestão, Instituto Politécnico de Viana do Castelo, 4900-347 Viana do Castelo, Portugal
| | - Ana Lúcia Barretto Penna
- Institute of Biosciences, Humanities and Exact Sciences, Food Engineering and Technology Department, UNESP—São Paulo State University, São José do Rio Preto 15054-000, SP, Brazil; (L.F.S.); (T.N.S.); (D.A.M.); (A.C.C.)
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5
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Nguyen HTH, Gomes Reis M, Wa Y, Alfante R, Chanyi RM, Altermann E, Day L. Differences in Aroma Metabolite Profile, Microstructure, and Rheological Properties of Fermented Milk Using Different Cultures. Foods 2023; 12:foods12091875. [PMID: 37174413 PMCID: PMC10178633 DOI: 10.3390/foods12091875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
Texture and flavour are the key attributes determining sensory quality and are highly affected by starter cultures. A selection of phenotypic strains is needed to create diverse texture and flavour to meet consumers' preferences. In this study, the use of five lactic acid bacteria strains in the production of fermented milk, along with the metabolite profiles, microstructure, and rheological properties of the fermented milk samples, was investigated. Our results showed that Lactobacillus helveticus (LH) and Streptococcus thermophilus (ST) had a stronger acidification during fermentation but resulted in products with a coarser protein network compared to Lactococcus lactis (BL1) and Leuconostoc mesenteroides (CL3). Milk fermented by LH had the highest viscosity and exopolysaccharide concentration, while milk fermented by ST had the highest concentration of diacetyl. Although Leuconostoc pseudomesenteroides (CL3ST) had a minimal acidification capability, it produced high levels of ethyl-derived compounds associated with sweet, fruity, and floral fragrances. The results demonstrated that LH and ST could be used as starter cultures targeting fermented milks with different viscosities, while BL1, CL3, and CL3ST are suitable as adjunct cultures to impact different acidic sharpness and flavour notes.
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Affiliation(s)
- Hanh T H Nguyen
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
| | - Mariza Gomes Reis
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
| | - Yunchao Wa
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, China
| | - Renna Alfante
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
| | - Ryan M Chanyi
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
- School of Veterinary Science, Massey University, Palmerston North 4100, New Zealand
| | - Eric Altermann
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
- School of Veterinary Science, Massey University, Palmerston North 4100, New Zealand
| | - Li Day
- AgResearch Ltd., Te Ohu Rangahau Kai, Palmerston North 4474, New Zealand
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Rossi F. Special Issue "Functional Characterization of Lactic Acid Bacteria": Editorial. Microorganisms 2023; 11:1190. [PMID: 37317164 DOI: 10.3390/microorganisms11051190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 04/25/2023] [Indexed: 06/16/2023] Open
Abstract
Lactic acid bacteria (LAB) are a diverse group of microorganisms of the order Lactobacillales in the Bacillota phylum, subdivision Bacilli, comprising, at this stage of taxonomic descriptions six families (Aerococcaceae, Carnobacteriaceae, Enterococcaceae, Lactobacillaceae, Leuconostocaceae and Streptococcaceae) [...].
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Affiliation(s)
- Franca Rossi
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Sezione di Campobasso, 86100 Campobasso, Italy
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7
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Effect of stress factors on the production of biogenic amines by lactic acid bacteria isolated from fermented Mexican foods (cheese and beer). Food Control 2022. [DOI: 10.1016/j.foodcont.2022.109553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chen S, Liu S, Ma J, Xu X, Wang H. Evaluation of the spoilage heterogeneity of meat-borne Leuconostoc mesenteroides by metabonomics and in-situ analysis. Food Res Int 2022; 156:111365. [DOI: 10.1016/j.foodres.2022.111365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/04/2022] [Accepted: 05/10/2022] [Indexed: 01/23/2023]
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Kumar S, Bansal K, Sethi SK. Comparative genomics analysis of genus Leuconostoc resolves its taxonomy and elucidates its biotechnological importance. Food Microbiol 2022; 106:104039. [DOI: 10.1016/j.fm.2022.104039] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 04/04/2022] [Accepted: 04/12/2022] [Indexed: 11/27/2022]
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Assessment of the Spoilage Microbiota during Refrigerated (4 °C) Vacuum-Packed Storage of Fresh Greek Anthotyros Whey Cheese without or with a Crude Enterocin A-B-P-Containing Extract. Foods 2021; 10:foods10122946. [PMID: 34945498 PMCID: PMC8701269 DOI: 10.3390/foods10122946] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/21/2022] Open
Abstract
Although fresh whey cheeses are prone to rapid deterioration, mainly by psychrotrophic Gram-negative bacteria and lactic acid bacteria (LAB), data on the specific spoilage species in traditional Greek whey cheeses are scarce. Therefore, this study quantified growth and characterized the primary spoilage bacteria in fresh Anthotyros whey cheeses stored at 4 °C in a vacuum for 40 days, without or with an added 5% (v/w) of an enterocin A-B-P crude extract (CEntE). Psychrotrophic Pseudomonas spp., Aeromonas spp., Hafnia spp. and Serratia spp. grew faster than LAB during early storage. However, LAB outgrew the Gram-negative bacteria and prevailed by mid to late storage in all cheese batches, causing a strong or milder batch-dependent natural acidification. Two major non-slime-producing and two minor biotypes of Leuconostoc-like bacteria, all identified as Leuconostoc mesenteroides by 16S rRNA sequencing, dominated the LAB association (76.7%), which also included four subdominant Carnobacterium maltaromaticum biotypes (10.9%), one Leuconostoc lactis biotype (3.3%) and few Lactococcus (1.6%), mesophilic Lactobacillus (0.8%) and Enterococcus (0.8%). Growth and distribution of LAB and Gram-negative species were strongly batch-dependent and plant-dependent. The CEntE neither retarded growth nor altered the whey cheese spoilage association but enhanced LAB growth and the declines of Gram-negative bacteria by late storage.
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