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Residence Time (Holding Time) Testing and Verification

Residence Time (Holding Time) Testing and Verification

Saline conductivity method using Lumenite Control Technology MTC-3000 pasteurization testing systemPasteurisation

To ensure all harmful micro-organisms are killed, pasteurisation involves heating the product to recognised international standards before it is cooled again. A combination of time and temperature is used to ensure that the taste, appearance and nutritional value of the product are not altered.

The holding time should be established as a “Critical Control Point” in any maintenance and preventative maintenance system.  Without the monitoring and measuring of this critical aspect of the pasteurisation process, the likelihood of product safety hazards could occur with the possibility of damage to your brand image which can be caused by negative media attention.

Independent Integrity Inspection Limited (INDEi) provides the expertise and the solution to certify the holding time process/verification to the standards accepted by food safety directives, standards and supermarkets, using equipment designed and manufactured for holding time testing.

INDEi offers the holding time analysis system as part of the overall periodic maintenance system for plate and tubular pasteurisers and heat exchangers or as a stand-alone test complying with legislation with a reliable, hygienic, accurate and traceability measuring solution.

Saline Conductivity testing method

Using the saline conductivity method and equipment provided by Lumenite Control Technology, the Company is enabled to reproduce the results time and time again, year after year as long as the critical components have not been changed ie pump, length of holding tube.

The saline conductivity testing method is the traditional international recognised method where a saline solution is injected at the starting point of the holding tube and is detected by a conductivity probe. When the solution has reached the other conductivity probe, the time is calculated.

Thermal Check testing method

The thermal check method is a non-intrusive test and can be carried out during production. Thermocouples are placed at the beginning and the end of the holding tubes/section, a heat rise is applied to the processing plant which is detected by the Thermal Laptop and the time is calculated.


Saline conductivity method using Lumenite Control Technology MTC-3000 pasteurization testing system

Whether you need to meet ISO 9001, BRC, IFS, ISO 22000 or other industry requirements, INDEi delivers. 

From pasteuriser and heat exchanger testing to flow rate confirmation and tank inspection to spray dryer inspection, process plant validation and preventative maintenance INDEi ensures compliance.


We provide both methods/services to give you the option to choose your preferred method of holding time testing that’s most suitable to your heat exchangers and production.
Not sure which testing method would be better for you? Get in touch with our knowledgeable technical team today to discuss your individual needs and requirements.
Contact Independent integrity Inspection Limited
ISO 9001 : 2015 registered quality management system.  BSI certificate number FS 510584