The Acoustiscan Scanner for Product Characterisation

This apparatus is a fast and easy way to determine shelf life in emulsions. It scans a tube containing the sample under test, which can be between 10 mm and 250 mm high and plots acoustic parameters as a function of height. This process may be repeated as many times as required without disturbing the sample. In this way a picture of the changes in the sample can be detected, long before theyare visually apparent.

Up to six different samples may be scanned simultaneously due to the incorporation of a six-cell sample changer in the instrument.

he apparatus works by measuring acoustic parameters such as sound speed at different heights up the tube. It is different to accelerated shelf life tests since the acoustic signal is very sensitive to the very small changes which precede visually apparent creaming or sedimentation, which are detected under normal storage conditions. It is also sensitive to other changes in the material, for example crystallization, flocculation, Ostwald ripening and phase separation.

An acoustic pulse is transmitted right through the sample and a measurement of the bulk properties taken; unlike some non-acoustic scanners which measure an atypical layer close to the sample surface.

The measurements are non-invasive and non-destructive. The sample may generally be measured under similar conditions to which it would be stored. A high level of automation combined with Windows software greatly simplifies operation.

The apparatus is unique, was designed and built in the School of Food Science and Nutrition, University of Leeds and is the product of many years of experience of colloid characterisation using ultrasound. The School of Food Science and Nutrition is a world centre of excellence in Food Colloid Science and has a record of innovation for instrumentation.