From April 2019
How to reduce costs and improve quality by optimising thermal processing
What is thermal processing?
Thermal processing is an important method of food
preservation, controlling the presence of microbial spoilage
organisms in food stuffs and ensuring products are safe. A
growing range of food products is preserved using thermal
technologies, ranging from sterilisation, such as canning and
ultra high temperature (UHT) processing, to milder
pasteurisation heat treatments, such as high temperature
short time (HTST), steam/air oven cooking and
pasteurisation tunnels.
Why optimise thermal processing?
Preservation of a food’s nutritional and sensory attributes
during heat processing is very important for quality and
consumer acceptance of the product. As the thermal
stability of nutrients or quality attributes often differ from
pathogenic organisms, it can be challenging to find an
optimal thermal process, but it is possible.
Process optimisation, i.e. a reduction in over-processing, can aid the retention of natural or added quality components such as colour, vitamins and antioxidants after heating. It can also extend product shelf-life, increase product throughput and reduce energy consumption of equipment.
How can thermal processing
be optimised for quality?
Thermal processes are primarily applied to assure product
safety. The time and temperature of the treatment can be
tailored to optimise quality - such as flavour, colour, texture
and vitamin or nutrient levels - without compromising safety.
Maximising the efficiency of the heat transfer is key when
optimising a thermal process for quality reasons. There are
several factors that affect the rate of heat transfer,
including, heating method, packaging type and product
composition. Adjusting any of these factors to improve
the rate of heat transfer can aid quality retention - and
sometimes a small adjustment can have a large impact.
Processes can be optimised to increase quality with the help of theoretical calculations and modelling software. These tools provide insights into heating effects on product properties without extensive trial work. For example, lower temperatures applied for longer periods may improve quality for some products, but higher temperatures applied for shorter periods of time may benefit others.
When should I optimise
my thermal process?
Quality optimisation work can be an easy add-on to a
thermal process validation project. Validation checks that
food safety requirements are met but optimising the
process can ensure that the product isn’t over processed,
potentially reducing time and energy requirements.
If you’re looking to improve existing processes, or to
explore the potential of new products and process
equipment, we can help you optimise your existing
processes using calculations, modelling or with on-site
trial work.
Contact: David Whittaker
+44(0)1386 842031
david.whittaker@campdenbri.co.uk