Contribution of natural milk culture to microbiota, safety and hygiene of raw milk cheese produced in alpine malga
Autor: | Michele Negrinotti, Enrico Novelli, Rosaria Lucchini, Barbara Cardazzo, Lisa Carraro, Stefania Balzan, Franco Fasoli, Giovanni Farina, Luca Fasolato |
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Jazyk: | angličtina |
Rok vydání: | 2018 |
Předmět: |
0301 basic medicine
Salmonella Biology medicine.disease_cause Article Milking 03 medical and health sciences Starter Listeria monocytogenes Cheese medicine Cheesemaking Food science Natural Milk Culture lcsh:TP368-456 food and beverages Hygiene Raw milk Contamination Malga lcsh:Food processing and manufacture 030104 developmental biology NGS Natural milk culture Food Science Coagulase NGS malga |
Zdroj: | Italian Journal of Food Safety, Vol 7, Iss 1 (2018) Italian Journal of Food Safety |
ISSN: | 2239-7132 |
Popis: | Processing of alpine milk in malga farms is carried out under conditions that can favor contamination by coliforms, coagulase-positive staphylococci, or pathogens such as Listeria monocytogenes. With the aim to improve the hygienic characteristics and safety of cheese produced in four malga farms the use of lyophilized Natural Milk Culture prepared with selected strains was tested. Two cheesemaking tests were carried out in the same day always starting from the same milk: in the first case following the malga recipe that uses either Natural Whey Culture or without the addition of a starter, in the second one using a Natural Milk Culture. Cheesemaking were carried out in four malga farms located in the west area of Trentino region within the same week. For hygienic and safety evaluation, aerobic colony count, coagulase-positive staphylococci, Escherichia coli, staphylococcal toxins, Listeria monocytogenes , and Salmonella spp, pH and aw were determined in raw milk from evening and morning milking, curd in vat, curd after extraction and two months-ripened cheese. Pathogens or toxins, high values of coagulase- positive staphylococci and E. coli were not found in cheese samples. However, in the curd coagulase-positive staphylococci reached values almost of 5 Log CFU/g in the two malga without starter cultures. The use of Natural Milk Culture reduced E. coli counts. In addition, DNA was extracted from cheese samples and from Natural Milk Culture and the composition of the microbial community determined by Next Generation Sequencing method. The determination of cheese microbial communities demonstrated that the use of Natural Milk Culture exerted different effects in the different malga, in any case preserving bacterial biodiversity. |
Databáze: | OpenAIRE |
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