חיפוש מתקדם
Raats, D., Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905, Israel
Offek, M., Institute for Soil, Water and Environmental Sciences, Volcani Research Center, P.O. Box 6, Bet Dagan 50250, Israel
Minz, D., Institute for Soil, Water and Environmental Sciences, Volcani Research Center, P.O. Box 6, Bet Dagan 50250, Israel
Halpern, M., Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905, Israel, Department of Science Education-Biology, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 36006, Israel
The impact of refrigeration on raw cow milk bacterial communities in three farm bulk tanks and three dairy plant silo tanks was studied using two methods: DGGE and cloning. Both methods demonstrated that bacterial taxonomic diversity decreased during refrigeration. . Gammaproteobacteria, especially . Pseudomonadales, dominated the milk after refrigeration. Farm samples and dairy plant samples differed in their microbial community composition, the former showing prevalence of Gram-positive bacteria affiliated with the classes . Bacilli, . Clostridia and . Actinobacteria, the latter showing prevalence of Gram-negative species belonging to the . Gammaproteobacteria class. . Actinobacteria prevalence in the farm milk samples immediately after collection stood at about 25% of the clones. A previous study had found that psychrotolerant . Actinobacteria identified in raw cow milk demonstrated both lipolytic and proteolytic enzymatic activity. Thus, we conclude that although . Pseudomonadales play an important role in milk spoilage after long periods of cold incubation, . Actinobacteria occurrence may play an important role when assessing the quality of milk arriving at the dairy plant from different farms. As new cooling technologies reduce the initial bacterial counts of milk to very low levels, more sensitive and efficient methods to evaluate the bacterial quality of raw milk are required. The present findings are an important step towards achieving this goal. © 2010 Elsevier Ltd.
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הספר "אוצר וולקני"
אודות
תנאי שימוש
Molecular analysis of bacterial communities in raw cow milk and the impact of refrigeration on its structure and dynamics
28
Raats, D., Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905, Israel
Offek, M., Institute for Soil, Water and Environmental Sciences, Volcani Research Center, P.O. Box 6, Bet Dagan 50250, Israel
Minz, D., Institute for Soil, Water and Environmental Sciences, Volcani Research Center, P.O. Box 6, Bet Dagan 50250, Israel
Halpern, M., Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905, Israel, Department of Science Education-Biology, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 36006, Israel
Molecular analysis of bacterial communities in raw cow milk and the impact of refrigeration on its structure and dynamics
The impact of refrigeration on raw cow milk bacterial communities in three farm bulk tanks and three dairy plant silo tanks was studied using two methods: DGGE and cloning. Both methods demonstrated that bacterial taxonomic diversity decreased during refrigeration. . Gammaproteobacteria, especially . Pseudomonadales, dominated the milk after refrigeration. Farm samples and dairy plant samples differed in their microbial community composition, the former showing prevalence of Gram-positive bacteria affiliated with the classes . Bacilli, . Clostridia and . Actinobacteria, the latter showing prevalence of Gram-negative species belonging to the . Gammaproteobacteria class. . Actinobacteria prevalence in the farm milk samples immediately after collection stood at about 25% of the clones. A previous study had found that psychrotolerant . Actinobacteria identified in raw cow milk demonstrated both lipolytic and proteolytic enzymatic activity. Thus, we conclude that although . Pseudomonadales play an important role in milk spoilage after long periods of cold incubation, . Actinobacteria occurrence may play an important role when assessing the quality of milk arriving at the dairy plant from different farms. As new cooling technologies reduce the initial bacterial counts of milk to very low levels, more sensitive and efficient methods to evaluate the bacterial quality of raw milk are required. The present findings are an important step towards achieving this goal. © 2010 Elsevier Ltd.
Scientific Publication
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