By installing an oven using carbon infrared heaters from Heraeus Amba Australia , Oscar Mayer has been able to eliminate previous maintenance problems, improve energy efficiency and liberate valuable floor space, at its food manufacturing plant in Chard UK.
Oscar Mayer Ltd manufactures a range of potato-topped and crumb-topped ready meals for major high street supermarkets and it is important, in terms of final presentation, that the products are pre-browned.
Surface browning must be carried out without any after cooking of the product itself and this was previously done using long wave, metal sheathed infrared heaters.
However, this ageing system was proving increasingly difficult to maintain and the production line often had to be stopped to replace broken heating elements.
As a result, Oscar Mayer contacted specialists Protech Food Systems, of Bedford, to see if the surface browning operation could be carried out reliably and efficiently. Protech then co-operated with Heraeus to design and install a new oven incorporating the latest carbon infrared technology.
Carbon infrared is ideal for applications in the food industry, such as surface browning, as it delivers medium wave infrared radiation, which is suited to evaporating water from products, at a high power density.
This ensures that the surface of the food product rapidly achieves a sufficient temperature to drive away any local moisture and then cause browning without any possibility of after-cooking.
Following proving trials to establish the maximum production line speeds for crumb and potato topping, the system installed at Oscar Mayer features two infrared cassettes in an oven designed and built by Protech.
The first cassette is fitted with seven 7kW emitters and the second cassette has seven 7kW emitters and six 500W emitters to supplement the energy at the edges of the oven.
A control panel regulates the power emitted and the conveyor speed to suit the product being browned. It also incorporates emitter failure detection to ensure that, in the unlikely event of any emitter in either cassette being broken, this will be detected and an alarm raised.
Since installation, the new system has proved to be eminently reliable in operation, requiring little or no maintenance. Its compactness compared with the previous system has also allowed improvements to be made to the production line layout.
Moreover, significant energy savings have been achieved due to the fact that the carbon infrared system switches on and off virtually instantaneously, eliminating the need for lengthy pre-heating of the system to the required operating temperature at the start of each shift.
The fast response of the system also means that the heat can be removed quickly if the line stops unexpectedly, so minimising damage to product.