Effect of separator and two-stage bactofugation and their operating conditions on microbial load and dairy sludge volume

Authors
Samira Moradi 1
Fatemeh Zeraatpisheh 2
Hossein Zanganeh 3
Mehdi Ghajari shamoshaki 4
Alireza Vasiee 3
farideh tabatabaei yazdi 3
Seyed Ali Mortazavi 3
1 Department of Food Science, Faculty of Agricultural Engineering and Technology, University of Tehran, Tehran, Iran
2 Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
3 Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
4 Production Manager of Pegah Golestan Milk Factory, Iran
10.22034/FSCT.19.127.241
Abstract
Microbial quality of raw milk is very important in two respects. First, milk consumption itself plays a very significant role in people's food tables and its high microbial load endangers consumer health. Second, if the microbial quality of milk is not suitable, from a technology point of view, milk-derived products will not have a good quality. In this project, which has been carried out in collaboration with Pegah Golestan Company, the separation process (with separators) and double bactofugation was used to reduce microbial load with the aim of reducing milk heating (in order to reduce the nutritional value as a result of heat). Milk samples used for lactic cheese production in Golestan province were examined in 2020 and 2021. After the process, total microbial counting, aerobic and anaerobic spores were counted. The results showed that by using this method, the total microbial load, aerobic and anaerobic spores of the collected milks were reduced to an acceptable level throughout the year without decreasing the microbial quality of the produced cheese during the storage period. On the other hand, the process of separation and bactofugation produces dairy sludge. Normally, dairy sludge is removed every 20 minutes, which was performed in separator and bactofuge1 to 21 minutes to reduce dairy sludge.
Keywords
Milk
Microbial load
separator
bactofuge
Dairy sludge

Subjects

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Journal of food science and technology(Iran)
Volume 19, Issue 127 - Serial Number 127
September 2022
Pages 241-253