Weight Loss Mechanism’s
A cooking system give the operator control over the cooking time and the heat applied to a products surface, whereas the internal transport of heat from a products surface towards its core is governed by internal conduction.
The product thickness, or the distance from its surface to its centre, play a vital role in the core temperature progression and the progress tends to diminish towards the end of the cooking time as the temperature difference between the applied heat and the products surface temperature lessen.
Furthermore, a majority of food products tend to thickens when they heat up and contract. The growing thickness is counterproductive for transport of heat towards the core. Variations in product contraction produce different product thicknesses, which in turn caused temperature variations among products.
The level of heat treatment must be great enough to meet the minimum required core temperature in the thickest part of the products, causing thinner products, or thinner parts of products to be overcooked and loose more weight than necessary.
From the moment the core temperature of a chicken fillet reaches 60°C, the ongoing weight loss that take place is about 0.9% per minute throughout the remaining cooking time that is required to rise the core temperature another 12°C to meet the minimum required core temperature of 72°C.
Belt Grills give the operator control over a third parameter – the product thickness. They fully-cook 200 g. chicken fillets in under 5 minutes. When used as pre-cookers, they rise the core temperature from 2°C to 35°C in 1 minute before further cooking takes place in a spiral- or linear oven system.
Reduce weight loss by reducing variations in product thickness. Reduce the cooking time needed to rise the core temperature from 60°C to 72°C.