Effect of different heat treatments on the demise of Salmonella DNA

doi:10.7506/spkx1002-6630-201305010

Abstract

Abstract:

In order to explore the impact of a variety of heat treatments on the detection and extinction of Salmonella
DNA, five kinds of common heat treatment methods during the processing and consumption of meat were applied to kill
Salmonella. The genomic DNA of treated bacteria after a period of storage at room temperature was extracted. The results
showed that heat treatment at 65 ℃ for 20 min, 85 ℃ for 30 min, boiling for 3 min, and sterilization at 121 ℃ for 15 min
could completely inactivate Salmonella, but boiling for 2 min cannot inactivate Salmonella. A large number of genomic
DNA remained in bacilli treated by heating at 65 ℃ for 20 min and 85 ℃ for 30 min, and exhibited a slow demise as well
as the bands was still visible after storage for 18 days. The DNA bands of bacilli treated by boiling for 3 min was very weak
and disappeared after four days. In contrast, the sterilization at 121 ℃ for 15 min had no visible bands. During a long storage
period, a large number of gene fragments also remained in dead bacilli. The higher heating temperature resulted in the faster
degeneration of Salmonella DNA. Therefore, in order to keep safety, the meat should be boiled for at least 3 min.

Key words: Salmonella, meat, genomic DNA

CLC Number:

TS201.3

LIU Jie，LI Miao-yun*，ZHAO Gai-ming，LIU Yan-xia，GAO Xiao-ping，TIAN Wei，HUANG Xian-qing，ZHANG Qiu-hui. Effect of different heat treatments on the demise of Salmonella DNA[J]. FOOD SCIENCE, 2013, 34(5): 46-49.

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