1
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Lan X, Wu S, Du Q, Min L. The Investigation of Changes in Bacterial Community of Pasteurized Milk during Cold Storage. Foods 2024; 13:451. [PMID: 38338585 PMCID: PMC10855270 DOI: 10.3390/foods13030451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/25/2023] [Accepted: 12/30/2023] [Indexed: 02/12/2024] Open
Abstract
The quality of pasteurized milk is commonly assessed through microbiological analysis, with variations in storage conditions significantly impacting the suppression of bacterial growth throughout the milk's shelf life. This study investigated the dynamics of total bacterial counts (TBCs) and bacterial community shifts in milk that underwent pasteurization at 80 °C for 15 s. The milk was subsequently stored at 4 °C for varying intervals of 1, 4, 7, 10, 13, and 16 days. Culture-based testing revealed a significant TBC increase during the storage period spanning 1 to 16 days (up to -log10 4.2 CFU/mL at day 16). The TBC in pasteurized milk exhibited accelerated microbial growth from day 13 onwards, ultimately peaking on day 16. Bacillus was detected through 16S rRNA identification. Principal component analysis demonstrated a significant impact of storage time on bacterial communities in pasteurized milk. Analysis of bacterial diversity revealed a negative correlation between the Shannon index and the duration of pasteurized milk storage. Using high-throughput sequencing, Streptococcus and Acinetobacter were detected as prevalent bacterial genera, with Streptococcus dysgalactiae and Streptococcus uberis showing as dominant taxa. The presence of Streptococcus dysgalactiae and Streptococcus uberis in pasteurized milk might be attributed to the initial contamination from raw milk with mastitis. This study offers new evidence of the prevalence of bacterial community in pasteurized milk, thereby adding value to the enhancement of quality control and the development of strategies for reducing microbial risks.
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Affiliation(s)
- Xinyi Lan
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China;
| | - Shuyan Wu
- Hopkirk Research Institute, AgResearch Ltd., Palmerston North 4442, New Zealand;
| | - Qijing Du
- Grasslands Research Centre, AgResearch Ltd., Palmerston North 4472, New Zealand;
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, China
| | - Li Min
- Ministry of Agriculture Key Laboratory of Animal Nutrition and Feed Science in South China, Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
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2
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Zarei M, Elmi Anvari S, Maktabi S, Saris PEJ, Yousefvand A. Identification, proteolytic activity quantification and biofilm-forming characterization of Gram-positive, proteolytic, psychrotrophic bacteria isolated from cold raw milk. PLoS One 2023; 18:e0290953. [PMID: 37703270 PMCID: PMC10499245 DOI: 10.1371/journal.pone.0290953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 08/19/2023] [Indexed: 09/15/2023] Open
Abstract
Psychrotrophic bacteria of raw milk face the dairy industry with significant spoilage and technological problems due to their ability to produce heat-resistant enzymes and biofilms. Despite extensive information about Gram-negative psychrotrophic bacteria in milk, little is known about Gram-positive psychrotrophic bacteria in milk, and their proteolytic activity and biofilm-forming characteristics. In the present study, Gram-positive, proteolytic, psychrotrophic bacteria of cold raw milk were identified, and their proteolytic activity and biofilm-forming capacity were quantified. In total, 12 genera and 22 species were represented among the bacterial isolates, however 50% belonged to three genera, namely Staphylococcus (19.4%), Bacillus (16.7%), and Enterococcus (13.9%). Different levels of proteolytic activity were detected in the identified isolates, even among the strains belonging to the same species. In addition, proteolytic activity was significantly higher at 25°C than at 7°C for all isolates. The crystal violet staining assay in polystyrene microtitre plates revealed a high level of variation in the biofilm-forming capacity at 7°C. After 72 hours of incubation, 11.1% of the strains did not produce a biofilm, while 27.8%, 52.8%, and 8.3% produced low, moderate, and high amounts of biofilm on polystyrene, respectively. The psychrotrophic bacteria were also able to produce biofilms on the surface of stainless steel coupons in ultra-high temperature milk after 72 h of incubation at 7°C; the number of attached cells ranged from 1.34 to 5.11 log cfu/cm2. These results expand the knowledge related to the proteolytic activity and biofilm-forming capacity of Gram-positive psychrotrophic milk bacteria.
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Affiliation(s)
- Mehdi Zarei
- Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Sahar Elmi Anvari
- Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Siavash Maktabi
- Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Per Erik Joakim Saris
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Amin Yousefvand
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
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3
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Wang J, Zhu X, Zhao Y, Liu H, Zhang Z, Yan L, Chen Y, Robertson ID, Guo A, Aleri JW. Prevalence and antimicrobial resistance of Salmonella and ESBL E. coli isolated from dairy cattle in Henan Province, China. Prev Vet Med 2023; 213:105856. [PMID: 36716653 DOI: 10.1016/j.prevetmed.2023.105856] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/06/2022] [Accepted: 01/21/2023] [Indexed: 01/25/2023]
Abstract
Salmonella and ESBL-producing E. coli pose a threat to public health through the food chain. A cross-sectional study was conducted to determine the prevalence and antimicrobial resistance of Salmonella and ESBL E. coli in apparently healthy lactating dairy cattle in Henan Province. Thirty-five lactating cows per farm were sampled by fecal swabbing from 38 farms, with samples being pooled to a total of 7 pooled samples per herd. Eight of the 266 pooled fecal samples (3.0%) were positive for Salmonella (95% confidence intervals (CI): 1.3, 5.8) with a herd-level Salmonella prevalence of 13.2% (95% CI: 4.4, 28.1). The within-herd prevalence for pooled samples for Salmonella ranged from 0.0% to 28.6%. A high proportion of resistance to tetracycline (6/8) and florfenicol (6/8) was obtained in the cultured Salmonella. Multi-drug resistant isolates were observed on 4/5 Salmonella-positive farms. ESBL E. coli were identified on all farms (100% - 34/34, 95% CI: 89.7, 100). All ESBL E. coli isolates (n = 216) contained the blaCTX-M gene and two isolates also contained the blaTEM gene. Our study reports the prevalence and antimicrobial resistance of Salmonella and ESBL E. coli in apparently healthy lactating dairy cows from Henan Province.
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Affiliation(s)
- Jie Wang
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, 6150 Western Australia, Australia; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Xiaojie Zhu
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, 6150 Western Australia, Australia; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Yuxi Zhao
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Huan Liu
- Henan Dairy Herd Improvement Center, Zhengzhou 450046, China.
| | - Zhen Zhang
- Henan Dairy Herd Improvement Center, Zhengzhou 450046, China.
| | - Lei Yan
- Henan Dairy Herd Improvement Center, Zhengzhou 450046, China.
| | - Yingyu Chen
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Ian D Robertson
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, 6150 Western Australia, Australia; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Aizhen Guo
- The State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, 6150 Western Australia, Australia; Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Joshua W Aleri
- School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, 6150 Western Australia, Australia; Centre for Animal Production and Health, Future Foods Institute, Murdoch University, 90 South Street, Murdoch, 6150 WA, Australia.
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4
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Ahmad N, Joji RM, Shahid M. Evolution and implementation of One Health to control the dissemination of antibiotic-resistant bacteria and resistance genes: A review. Front Cell Infect Microbiol 2023; 12:1065796. [PMID: 36726644 PMCID: PMC9884834 DOI: 10.3389/fcimb.2022.1065796] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 12/16/2022] [Indexed: 01/19/2023] Open
Abstract
Antibiotic resistance is a serious threat to humanity and its environment. Aberrant usage of antibiotics in the human, animal, and environmental sectors, as well as the dissemination of resistant bacteria and resistance genes among these sectors and globally, are all contributing factors. In humans, antibiotics are generally used to treat infections and prevent illnesses. Antibiotic usage in food-producing animals has lately emerged as a major public health concern. These medicines are currently being utilized to prevent and treat infectious diseases and also for its growth-promoting qualities. These methods have resulted in the induction and spread of antibiotic resistant infections from animals to humans. Antibiotics can be introduced into the environment from a variety of sources, including human wastes, veterinary wastes, and livestock husbandry waste. The soil has been recognized as a reservoir of ABR genes, not only because of the presence of a wide and varied range of bacteria capable of producing natural antibiotics but also for the usage of natural manure on crop fields, which may contain ABR genes or antibiotics. Fears about the human health hazards of ABR related to environmental antibiotic residues include the possible threat of modifying the human microbiota and promoting the rise and selection of resistant bacteria, and the possible danger of generating a selection pressure on the environmental microflora resulting in environmental antibiotic resistance. Because of the connectivity of these sectors, antibiotic use, antibiotic residue persistence, and the existence of antibiotic-resistant bacteria in human-animal-environment habitats are all linked to the One Health triangle. The pillars of support including rigorous ABR surveillance among different sectors individually and in combination, and at national and international level, overcoming laboratory resource challenges, and core plan and action execution should be strictly implemented to combat and contain ABR under one health approach. Implementing One Health could help to avoid the emergence and dissemination of antibiotic resistance while also promoting a healthier One World. This review aims to emphasize antibiotic resistance and its regulatory approaches from the perspective of One Health by highlighting the interconnectedness and multi-sectoral nature of the human, animal, and environmental health or ill-health facets.
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5
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Feliciano RJ, Boué G, Mohssin F, Huseini MM, Membré JM. Raw milk quality in large-scale farms under hot weather conditions: learnings from one-year quality control data. J Food Compost Anal 2023. [DOI: 10.1016/j.jfca.2023.105127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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6
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Gajewska J, Zakrzewski A, Chajęcka-Wierzchowska W, Zadernowska A. Meta-analysis of the global occurrence of S. aureus in raw cattle milk and artisanal cheeses. Food Control 2023. [DOI: 10.1016/j.foodcont.2023.109603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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7
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Joubrane K, Jammoul A, Daher R, Ayoub S, El Jed M, Hneino M, El Hawari K, Al Iskandarani M, Daher Z. Microbiological contamination, antimicrobial residues, and antimicrobial resistance in raw bovine milk in Lebanon. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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8
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Sakaridis I, Psomas E, Karatzia MA, Samouris G. Hygiene and Safety of Hard Cheese Made from Raw Cows' Milk. Vet Sci 2022; 9:vetsci9100569. [PMID: 36288182 PMCID: PMC9609050 DOI: 10.3390/vetsci9100569] [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] [Received: 07/26/2022] [Revised: 08/22/2022] [Accepted: 10/12/2022] [Indexed: 11/05/2022] Open
Abstract
Simple Summary Raw cheeses have gained the preference of some consumers because of their intense and stronger taste compared with that of pasteurised cheeses. The pasteurization of raw milk causes the inactivation of the pathogenic and beneficial microorganisms of milk and of enzymes such as proteases and lipases which play a significant role in enhancing the unique flavour of raw cheeses. This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. The microbiological quality of raw milk was found generally good and was improved throughout the experiments. For the cheese samples, a small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. The outcome of our study was that the use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products. Abstract This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. Furthermore, the pH, the moisture and salt concentration were also monitored throughout processing, ripening and storage. Seven cheesemaking trials took place along with the microbiological and physicochemical analysis of the milk, curd and cheese produced. The milk used for the cheesemaking, two curd samples before the heating and two after the heating, two cheese samples at days 3, 7, 15, 30, 60 and 90 were subjected to microbiological analysis for total mesophilic bacterial count (for milk only), Enterobacteriaceae, E. coli, Staphylococcus, Salmonella, Listeria, and Clostridium. The microbiological quality of raw milk was found to be good. It was initially slightly above the EU limit but improvements associated with farm biosecurity and milking equipment hygiene led to a significantly improved milk quality. A small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. In two cheesemaking trials, Clostridium perfringens and Salmonella spp. were detected, the first originating from the milk and the second from the environment. The use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products.
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Affiliation(s)
- Ioannis Sakaridis
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
- Correspondence:
| | - Evdoxios Psomas
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
| | - Maria-Anastasia Karatzia
- Research Institute of Animal Science, Hellenic Agricultural Organization-Demeter, 58100 Giannitsa, Greece
| | - Georgios Samouris
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
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9
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Bacterial Milk Quality along the Value Chain in Smallholder Dairy Production. ScientificWorldJournal 2022; 2022:7967569. [PMID: 36187286 PMCID: PMC9519332 DOI: 10.1155/2022/7967569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/05/2022] [Indexed: 11/18/2022] Open
Abstract
This study aimed to evaluate the microbial quality of raw milk along the milk value chain at Africa University (AU). Eighteen Holstein-Friesian cows were used in this experiment. A total of 270 milk samples were collected for laboratory analysis at three different stages, during milking (DM), from the bulk tank (BT), and at the dining hall (DH), to determine the total bacterial count (TBC), Escherichia coli, and Salmonella enterica. Samples were cultured in Petri dishes using an appropriate medium for 48 hours. The plate count method was used to determine the quantity of bacteria. Data were analyzed using GLM SPSS. The results indicated that TBC increased (
< 0.05) from one site to the next along the value chain, yet it undulates when measured over time. Escherichia. coli and S. enterica counts increased (
< 0.05) at the last site of collection and the highest counts were recorded in week two. In conclusion, the current study indicates the hygiene of the dairy parlor with very low TBC, E. coli, and S. enterica counts during milking and bulk tank storage and that the relationship between TBC and E. coli is nonlinear with respect to time.
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10
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Liu H, Dong L, Zhao Y, Meng L, Wang J, Wang C, Zheng N. Antimicrobial Susceptibility, and Molecular Characterization of Staphylococcus aureus Isolated From Different Raw Milk Samples in China. Front Microbiol 2022; 13:840670. [PMID: 35633704 PMCID: PMC9136321 DOI: 10.3389/fmicb.2022.840670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is one of the main pathogens in different raw milk and dairy products, which may lead to economic losses. Staphylococcus aureus is a significant and costly public health concern because it may enter the human food chain and contaminate milk causing foodborne illness. This study aimed to investigate the prevalence, antimicrobial susceptibility and virulence genes of S. aureus in raw milks. In total, 125 raw milk samples collected from goat (n = 50), buffalo (n = 25), camel (n = 25), and yak (n = 25) were collected from 5 provinces in China in 2016. Out of 125 samples, 36 (28.8%) S. aureus were isolated (16 from goat, 9 from buffalo, 6 from camel, and 5 from yak). Out of 36 S. aureus, 26 strains (26/36, 72.2%) showed antibiotics resistance, and 6 strains isolated from goats were identified as methicillin-resistant S. aureus (MRSA). The antimicrobial resistance against Penicillin G, tetracycline and gentamicin was 50% (18/36), 41.7% (15/36), and 36.1% (13/36), respectively. 19 S. aureus (52.8%) were considered as multidrug resistant. The highest prevalence of resistant S. aureus was observed in goat milk (13/36, 36.1%). Among the 36 strains, 16 isolates harbored three or more resistant genes. The resistance genes were detected in 25 S. aureus, including 13 strains in goat, 5 strains in buffalo, 4 strains in camel, and 3 strains in yak. Among the 26 resistant strains, 61.5% of isolates harbored three or more resistant genes. The resistance genes were detected in 25 S. aureus, including 13 strains in goat milk, 5 strains in buffalo milk, 4 strains in camel milk, and 3 strains in yak milk. The most predominant resistance genes were blaZ (18/26, 69.2%), aac6′-aph2″ (13/26, 50.0%), and tet(M) (10/26, 38.5%). The mecA, ant(6)-Ia and fexA gene were only detected in S. aureus from goat milk. The most predominant toxin gene were sec (8/26, 30.8%). The majority of S. aureus were multidrug resistant and carried multiple virulence genes, which may pose potential risk to public health. Our findings indicated that the prevalence and antimicrobial resistance of S. aureus was a serious concern in different raw milks in China, especially goat milks.
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Affiliation(s)
- Huimin Liu
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Ministry of Agriculture—Milk and Dairy Product Inspection Center (Beijing), Beijing, China
| | - Lei Dong
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Ministry of Agriculture—Milk and Dairy Product Inspection Center (Beijing), Beijing, China
| | - Yankun Zhao
- Institute of Quality Standard and Testing Technology, Xinjiang Academy of Agricultural Sciences, Urumqi, China
| | - Lu Meng
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Ministry of Agriculture—Milk and Dairy Product Inspection Center (Beijing), Beijing, China
| | - Jiaqi Wang
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Ministry of Agriculture—Milk and Dairy Product Inspection Center (Beijing), Beijing, China
| | - Cheng Wang
- Institute of Quality Standard and Testing Technology, Xinjiang Academy of Agricultural Sciences, Urumqi, China
| | - Nan Zheng
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
- Ministry of Agriculture—Milk and Dairy Product Inspection Center (Beijing), Beijing, China
- *Correspondence: Nan Zheng,
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11
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Taghizadeh M, Nematollahi A, Bashiry M, Javanmardi F, Mousavil M, Hosseini H. The global prevalence of Campylobacter spp. in milk A systematic review and meta-analysis. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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12
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Liu H, Meng L, Dong L, Zhang Y, Wang J, Zheng N. Prevalence, Antimicrobial Susceptibility, and Molecular Characterization of Escherichia coli Isolated From Raw Milk in Dairy Herds in Northern China. Front Microbiol 2021; 12:730656. [PMID: 34630355 PMCID: PMC8500479 DOI: 10.3389/fmicb.2021.730656] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 08/26/2021] [Indexed: 11/13/2022] Open
Abstract
Escherichia coli is a common bacterium in the intestines of animals, and it is also the major important cause of toxic mastitis, which is an acute or peracute disease that causes a higher incidence of death and culling of cattle. The purpose of this study was to investigate E. coli strains isolated from the raw milk of dairy cattle in Northern China, and the antibacterial susceptibility of these strains and essential virulence genes. From May to September 2015, 195 raw milk samples were collected from 195 dairy farms located in Northern China. Among the samples, 67 (34.4%) samples were positive for E. coli. About 67 E. coli strains were isolated from these 67 samples. The prevalence of Shiga toxin-producing E. coli (STEC), enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), and enteroinvasive E. coli (EIEC) were 9, 6, 4.5, and 1.5%, respectively. Among the virulence genes detected, stx1 was the most prevalent (6/67, 9%) gene, followed by eae (3/67, 4.5%), and estB (2/67, 3%). Moreover, the strains exhibited different resistance levels to ampicillin (46.3%), amoxicillin-clavulanic acid (16.4%), trimethoprim-sulfamethoxazole (13.4%), tetracycline (13.4%), cefoxitin (11.9%), chloramphenicol (7.5%), kanamycin (7.5%), streptomycin (6.0%), tobramycin (4.5%), azithromycin (4.5%), and ciprofloxacin (1.5%). All of the E. coli isolates were susceptible to gentamicin. The prevalence of β-lactamase-encoding genes was 34.3% in 67 E. coli isolates and 45% in 40 β-lactam-resistance E. coli isolates. The overall prevalence of bla SHV, bla TEM, bla CMY, and bla CTX-M genes were 1.5, 20.9, 10.4, and 1.5%, respectively. Nine non-pathogenic E. coli isolates also carried β-lactamase resistance genes, which may transfer to other pathogenic E. coli and pose a threat to the farm's mastitis management projects. Our results showed that most of E. coli were multidrug resistant and possessed multiple virulence genes, which may have a huge potential hazard with public health, and antibiotic resistance of E. coli was prevalent in dairy herds in Northern China, and ampicillin should be used cautiously for mastitis caused by E. coli in Northern China.
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Affiliation(s)
- Huimin Liu
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lu Meng
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lei Dong
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yangdong Zhang
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiaqi Wang
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Nan Zheng
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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13
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Brodziak A, Wajs J, Zuba-Ciszewska M, Król J, Stobiecka M, Jańczuk A. Organic versus Conventional Raw Cow Milk as Material for Processing. Animals (Basel) 2021; 11:ani11102760. [PMID: 34679781 PMCID: PMC8532914 DOI: 10.3390/ani11102760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 01/10/2023] Open
Abstract
Milk, as one of the basic raw materials of animal origin, must be of adequate hygienic and physicochemical quality for processing. The aim of the article was to compare the quality of raw milk from three production systems, intensive, traditional (together referred to as conventional), and organic, as material for processing, as well as the quality of products made from it. Particular attention was focused on hygienic quality (somatic cell count and total bacterial count), physical characteristics (acidity), basic nutritional value (content of dry matter, total protein, casein, fat, and lactose), content of health-promoting substances (whey proteins, fatty acids, vitamins, and minerals), and technological parameters (rennet clotting time, heat stability, and protein-to-fat ratio). Research assessing the quality of organic milk and dairy products is significantly less extensive (if available at all) than for milk from conventional production (intensive and traditional). The available reports indicate that raw milk from organic farms is more valuable, especially in terms of the content of health-promoting compounds, including vitamins, fatty acids, whey proteins, and minerals. This applies to organic dairy products as well, mainly cheese and yoghurt. This is explained by the fact that organic farming requires that animals are kept in the pasture. However, the hygienic quality of the raw milk, and often the products as well, raises some concerns; for this reason, organic milk producers should be supported in this regard, e.g., through consultancy and training in Good Hygienic Practices. Importantly, milk production in the traditional and organic systems is in line with the concept of the European Green Deal.
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Affiliation(s)
- Aneta Brodziak
- Institute of Quality Assessment and Processing of Animal Products, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland; (A.B.); (J.K.); (M.S.); (A.J.)
| | - Joanna Wajs
- Institute of Quality Assessment and Processing of Animal Products, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland; (A.B.); (J.K.); (M.S.); (A.J.)
- Correspondence: ; Tel.: +48-814456836
| | - Maria Zuba-Ciszewska
- Institute of Economics and Finance, Faculty of Social Sciences, The John Paul II Catholic University of Lublin, Racławickie 14, 20-950 Lublin, Poland;
| | - Jolanta Król
- Institute of Quality Assessment and Processing of Animal Products, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland; (A.B.); (J.K.); (M.S.); (A.J.)
| | - Magdalena Stobiecka
- Institute of Quality Assessment and Processing of Animal Products, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland; (A.B.); (J.K.); (M.S.); (A.J.)
| | - Anna Jańczuk
- Institute of Quality Assessment and Processing of Animal Products, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland; (A.B.); (J.K.); (M.S.); (A.J.)
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14
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Cao T, Liu P, Li Y, Cui M, Zhang C, Wang Y, Shen Z, Shen J, Ke Y, Wang S, Wu Y. Prevalence of Salmonella and Antimicrobial Resistance in Isolates from Food Animals - Six PLADs, China, 2019. China CDC Wkly 2021; 3:514-517. [PMID: 34594924 PMCID: PMC8393044 DOI: 10.46234/ccdcw2021.132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 06/09/2021] [Indexed: 11/15/2022] Open
Abstract
What is already known about this topic? Salmonella causes acute and chronic diseases in food animals, and infected food animals are one of the most important source of human infection.
What does this report contribute? The prevalence of Salmonella was 10.5% in chicken samples, 24.4% in pig, 23.3% in duck, and 29.4% in milk. Salmonella isolates were highly resistant to ampicillin (59.60%).
What are the implications for public health practices? Data on Salmonella infections among food animals in China could help identify sources and factors related to the spread of Salmonella in food animals and food production chains.
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Affiliation(s)
- Tingting Cao
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Peng Liu
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yiming Li
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Mingquan Cui
- China Institute of Veterinary Drug Control, Beijing, China
| | - Chunping Zhang
- China Institute of Veterinary Drug Control, Beijing, China
| | - Yang Wang
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhangqi Shen
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jianzhong Shen
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yuebin Ke
- Key Laboratory of Molecular Epidemiology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen, Guangdong, China
| | - Shaolin Wang
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yongning Wu
- National Health Commission Key Laboratory of Food Safety Risk Assessment, Food Safety Research Unit (2019RU014) of Chinese Academy of Medical Science, China National Center for Food Safety Risk Assessment, Beijing, China
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15
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Rios-Muñiz D, Cerna-Cortes JF, Lopez-Saucedo C, Angeles-Morales E, Bobadilla-Del Valle M, Ponce-de Leon A, Estrada-Garcia T. Longitudinal Analysis of the Microbiological Quality of Raw Cow's Milk Samples Collected from Three Small Family Dairy Farms in Mexico over a 2-Year Period. J Food Prot 2019; 82:2194-2200. [PMID: 31742445 DOI: 10.4315/0362-028x.jfp-19-155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In Mexico, the total milk production that family dairy farms (FDF) contribute is ca. 35%, but this milk is not evaluated for microbiological quality. Forty percent of the milk and dairy products consumed by Mexicans is unpasteurized. In total, 24 raw cow's milk samples from three FDF (one sample per each season from each FDF for two sequent years) were characterized for the presence of food quality indicator organisms, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Mycobacterium spp., by standard procedures. Escherichia coli presence was also evaluated by a direct count method and diarrheagenic E. coli (DEC) by molecular methods. On the basis of Mexican guidelines for raw milk entering production, 42% of samples exceeded the aerobic mesophilic bacteria limits. A total of 83% raw milk samples were positive for total coliforms, 54% for fecal coliforms, and 46% for E. coli. Forty-three E. coli isolates were selected and characterized for the presence of 11 DEC loci; of theses, 40 isolates were negative for all DEC loci, and 3 isolates, all collected from the same sample, were Shiga toxin 2 (stx2) positive and O157 antigen negative, and one stx2 isolate was resistant to 6 of the 16 antibiotics tested. None of the 24 raw milk samples were positive for Salmonella enterica, L. monocytogenes, or staphylococcal enterotoxin. S. aureus was isolated from nine samples, of which only three samples harbored resistant isolates. From three samples, four nontuberculous mycobacterial isolates were recovered (Mycobacteroides chelonae, Mycobacteroides porcinum, and two Mycobacteroides abscessus). All four isolates produced biofilm and had sliding motility, and three isolates (M. porcinum and two M. abscessus) were resistant to the two antibiotics tested (clarithromycin and linezolid). FDF provide raw milk to a large proportion of the Mexican population, but its consumption could be harmful to health, emphasizing the need to implement national microbiological quality guidelines for raw milk intended for direct human consumption.
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Affiliation(s)
- Diana Rios-Muñiz
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Prolongación Carpio y Plan de Ayala S/N, Col. Casco de Santo Tomas, Ciudad de Mexico, CP 11340, Mexico.,Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Av. IPN 2508, Zacatenco, Mexico City, CP 07360, Mexico
| | - Jorge F Cerna-Cortes
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Prolongación Carpio y Plan de Ayala S/N, Col. Casco de Santo Tomas, Ciudad de Mexico, CP 11340, Mexico
| | - Catalina Lopez-Saucedo
- Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Av. IPN 2508, Zacatenco, Mexico City, CP 07360, Mexico
| | - Erika Angeles-Morales
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Prolongación Carpio y Plan de Ayala S/N, Col. Casco de Santo Tomas, Ciudad de Mexico, CP 11340, Mexico
| | - Miriam Bobadilla-Del Valle
- Departamento de Enfermedades Infecciosas, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubiran, Ciudad de Mexico, CP 14080, Mexico
| | - Alfredo Ponce-de Leon
- Departamento de Enfermedades Infecciosas, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubiran, Ciudad de Mexico, CP 14080, Mexico
| | - Teresa Estrada-Garcia
- Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Av. IPN 2508, Zacatenco, Mexico City, CP 07360, Mexico
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16
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Pannella G, Messia MC, Tremonte P, Tipaldi L, La Gatta B, Lombardi SJ, Succi M, Marconi E, Coppola R, Sorrentino E. Concerns and solutions for raw milk from vending machines. J FOOD PROCESS PRES 2019. [DOI: 10.1111/jfpp.14140] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Gianfranco Pannella
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Maria Cristina Messia
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Patrizio Tremonte
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Luca Tipaldi
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Barbara La Gatta
- Department of the Sciences of Agriculture, Food and Environment University of Foggia Foggia Italy
| | - Silvia Jane Lombardi
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Mariantonietta Succi
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Emanuele Marconi
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Raffaele Coppola
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
| | - Elena Sorrentino
- Department of Agricultural, Environmental and Food Sciences (DiAAA) University of Molise Campobasso Italy
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17
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Yuan L, Sadiq FA, Burmølle M, Wang NI, He G. Insights into Psychrotrophic Bacteria in Raw Milk: A Review. J Food Prot 2019; 82:1148-1159. [PMID: 31225978 DOI: 10.4315/0362-028x.jfp-19-032] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
HIGHLIGHTS Levels of psychrotrophic bacteria in raw milk are affected by to habitats and farm hygiene. Biofilms formed by psychrotrophic bacteria are persistent sources of contamination. Heat-stable enzymes produced by psychrotrophic bacteria compromise product quality. Various strategies are available for controlling dairy spoilage caused by psychrotrophic bacteria.
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Affiliation(s)
- Lei Yuan
- 1 College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, People's Republic of China.,2 Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Faizan A Sadiq
- 3 School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Mette Burmølle
- 2 Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen 2100, Denmark
| | - N I Wang
- 1 College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Guoqing He
- 1 College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, People's Republic of China
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18
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Li N, Wang Y, You C, Ren J, Chen W, Zheng H, Liu Z. Variation in Raw Milk Microbiota Throughout 12 Months and the Impact of Weather Conditions. Sci Rep 2018; 8:2371. [PMID: 29402950 PMCID: PMC5799204 DOI: 10.1038/s41598-018-20862-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 01/25/2018] [Indexed: 02/07/2023] Open
Abstract
Milk microbiota has a great influence on the safety and quality of dairy products. However, few studies have investigated the variations of bacterial composition in raw milk. In this study, raw milk samples were collected in 12 successive months, and their bacterial compositions were determined by 16 S rRNA gene sequencing. The highest diversity of bacterial composition was detected in June, while the lowest was in December. Firmicutes, Proteobacteria and Actinobacteria were the most abundant phyla and exhibited a counter-balanced relationship. Pseudomonas, Lactococcus and Acinetobacter were the most prevalent genera (>1%), and a tiny core microbiota (Acinetobacter and Pseudomonas) was observed. Temperature and humidity were the determining factors for most variation in bacterial compositions at both the phylum and genus levels. Higher abundances of Pseudomonas, Propionibacterium and Flavobacterium were correlated with low temperature. Furthermore, Pseudomonas/Propionibacterium and Lactobacillus/Bifidobacterium were two pairs of genera that had synergistic effects. Associations between the microbiota and milk quality parameters were analyzed. The abundances of Propionibacterium and Pseudoalteromonas were negatively correlated to total bacterial count, which meant that they helped to maintain milk quality, while a series of environmental microorganisms contributed to the spoilage of raw milk.
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Affiliation(s)
- Nan Li
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Synergetic Innovation Center for Food Safety and Nutrition, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, 200436, China
| | - Yuezhu Wang
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, 201203, China
| | - Chunping You
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Synergetic Innovation Center for Food Safety and Nutrition, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, 200436, China
| | - Jing Ren
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Synergetic Innovation Center for Food Safety and Nutrition, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, 200436, China
| | - Wanyi Chen
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Synergetic Innovation Center for Food Safety and Nutrition, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, 200436, China
| | - Huajun Zheng
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, 201203, China. .,Key Laboratory of Reproduction Regulation of NPFPC, Shanghai Institute of Planned Parenthood Research, IRD, Fudan University, Shanghai, 200032, China.
| | - Zhenmin Liu
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Synergetic Innovation Center for Food Safety and Nutrition, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Shanghai, 200436, China.
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19
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Kunová S, Golian J, Zeleňáková L, Lopašovský Ľ, Čuboň J, Haščík P, Kačániová M. Microbiological quality of fresh and heat treated cow's milk during storage. POTRAVINARSTVO 2017. [DOI: 10.5219/799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aim of the present study was to evaluate the microbiological quality of raw milk from milk vending machine and heat treated milk during storage. There were analyzed 120 samples of milk (30 samples of fresh milk, 30 samples of raw milk stored 4 day at 4 °C, 30 samples of heat treated milk - 70 °C stored 4 day at 4 °C and 30 samples of heat treated milk - 100 °C stored 4 day at 4 °C). Total viable counts (TVC), coliform bacteria (CB) and microscopic filamentous fungi (MFF) were determined by microbiological analysis. Plate dilution method were used for microbiological analysis. The number of total viable counts (TVC) in fresh milk ranged from 4.08 log KTJ.mL-1 to 4.89 CFU.mL-1. TVC in raw milk after storage ranged from 5.31 log CFU.mL-1 to 6.81 log CFU.mL-1. TVC in heat treated milk with temperature 70 °C after storage ranged from 3.89 log CFU.mL-1 to 4.45 log CFU.mL-1 and TVC in heat treated milk with temperature 100 °C after storage ranged from 2.96 log KTJ.mL-1 to 3.91 log KTJ.mL-1 in heat treated milk with temperature 100 °C after storage. The number of CB were in range from 1.49 log CFU.mL-1 to 1.89 log CFU.mL-1 in fresh milk, from 1.99 log CFU.mL-1 to 2.61 log CFU.mL-1 in raw stored milk. Coliform bacteria were not present in heat-treated milk samples. The values of MFF ranged from 0 log CFU.mL-1 to 2.01 log CFU.mL-1 in fresh milk, from 1.43 log CFU.mL-1 to 3.98 log CFU.mL-1 in raw milk after storage, from 1.33 log CFU.mL-1 to 3.41 log CFU.mL-1 in heat treated milk with temperature 70 °C after storage and from 1.30 log CFU.mL-1 to 3.32 log CFU.mL-1 in heat treated milk with temperature 100 °C after storage.
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