Kraft Foods, which owns chocolate maker Cadbury, has filed a patent for the manufacture of low-calorie chocolate. This new method is said to preserve quality and texture while extending shelf life.
Previous attempts to develop a low-calorie chocolate had resulted in a product that lacked both richness and the appropriate mouthfeel – texture, melting behaviour, firmness and snapping characteristics.
According to the patent application. “These shortcomings are particularly evident for the prior art chocolate-type products, which lack a texture similar to the texture of regular chocolates and a cocoa flavour similar to the flavour of regular chocolates.”
At the heart of the application is the use of a ‘structured liquid’ which allows increased moisture in the product, permitting a reduction in sugar and fat, so reducing calories.
The structured liquid is said to contain thermodynamically stable water, surfactant, co-surfactant and a non-aqueous component.
In chocolate manufacture the addition of up to 5% water to a chocolate mass reduces the processing window to less than one minute and necessitates the subsequent removal of the moisture.
The filing notes that a level of 5-to-10% water leads to almost instantaneous firming-up of a chocolate matrix and water levels beyond 10% lead to the development of viscoelastic properties which prevent processing of the resulting mass.
These difficulties are, according to the application, not encountered when using the structured liquid, because the water is not ‘free’ but ‘entrapped’ in a thermodynamically and kinetically stable state.
This leads to beneficial properties such as little, or no, agglomeration when incorporating the structured liquid into chocolate-type products, which are the result of its special wetting behaviour.