Fluke Datapaq Food Tracker User Manual page 37

Probe Selection and Placement
Probe Selection
Selection of thermocouple type and insulation (see p. 27 for the range
available) is based on the product and the process environment. Product size is
a prime consideration. In general, suitability is as follows:
Needle probes – Large meat products, vacuum packed products, canned and
bottled products, bread and cakes.
Core temperature probes – Smaller meat products (e.g. chicken parts), fish
and all frying processes, small cakes, soft or liquid products, environmental
monitoring.
Thermocouples generally suitable for food industry applications are type T or
type K; see p. 28 for temperature range and accuracy. For processes below
0°C/32°F (down to −40°C/−40°F), type T probes should be used.
The cable insulation material limits the actual operating temperature. Maximum
temperatures are:
Mineral insulation
PTFE
Measurement Type
Measurements will be made of air temperature, product core temperature and/
or surface temperature.
An array of air probes providing a view of temperature distribution across the
oven enables adjustment of heaters and/or baffles. Measurements in the core or
on the surface of the product characterize heat absorption from the air by
determining the actual temperature/time profile to which the product is
subjected. A combination of air and surface probes enables the rate of heat
absorption to be determined, and thus permits adjustments to optimize thermal
efficiency and product quality.
Probe Placement
For a reliable, repeatable and comparable assessment of thermal performance it
is essential that measurements are made in the same location, using the same
type of probe attached in the same way to the same type of product. In some
cases it is advisable to use a test fixture to ensure absolute repeatability. Note
also the following points essential to accurate and repeatable measurements:
• Probes must be attached and restrained to ensure they remain securely
placed in the product throughout the cooking process. The Datapaq food
tray and thermocouple jig (see below) are designed to facilitate this.
FOOD TR ACK ER
800°C/1,472°F
265°C/509°F
Running a Temperature Profile
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