Food Protection Trends - August 2010 - 476

the facility level. Engineering, operations and quality assurance teams were all involved in the chiller heat treatment planning as well as the ongoing treatment. The minimum effective parameters that completely dried chillers without impacting internal floor, walls and chilling equipment was found to be 50oC for 2 hours. The engineering team was given the responsibility of preparing chilling units for weekend heating, and no chiller is excluded from the heat treatment for more than 2 weeks. The operations team consolidates product into other chillers, ensuring that a gap around the chiller walls to be treated is maintained to allow airflow and passage of heaters and fans. The quality assurance team verifies temperature graphs displaying each of the chillers treated. As these protocols were developed by all the teams involved, standard operating procedures were readily taken into the GMP program. We have described a simple way to potentially reduce Listeria contamination in the post processing chiller environment. Certainly a limitation of this technique is the required redundancy of chillers, and it is recognized that many facilities do not operate with such a redundancy. Although this protocol is unable to completely eliminate Listeria, it does dry chillers, is easily taken up into the GMP program, produces no deleterious effects to the treated chillers and has significantly reduced environmental post cook chiller Listeria contamination.

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REFERENCES
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476 FOOD PROTECTION TRENDS | AUGUST 2010
Food Protection Trends - August 2010

Table of Contents for the Digital Edition of Food Protection Trends - August 2010
