FOOD & DRINK TECHNOLOGY 41


from two microns (µm) up to thirty millimetres (mm).


How it works Dynamic image analysis using a pulsed laser allows fast quantification of particle shape and size distribution. Due to the unique way in which the machine operates, scientists at Campden BRI can now analyse the shape of particles, as well as their size.


Dispersion is key to the way the system works because it allows a large number of particles to be imaged in a short space of time without any ‘overlaps’ occurring.


Te innovative, new particle shape and size analyser uses an extremely short exposure time capturing up to 450 images per second to allow fast methods of dispersion to be used while still providing clear images from particles travelling at high speeds guaranteeing proper dispersion of agglomerated, fine, and cohesive powders.


As images of the particles are captured in freefall, their orientations are completely random; this provides a much more accurate representation of particle size than can be obtained by static image analysis systems, yet the speed at which images are captured means particle edges are sharp and are independent of their position in the measuring zone.


Particle sizes between 2µm and 30mm can be measured and primary measurement data can be evaluated in individually definable formats. Rapid image capture, allowing the recording of up to 450 images per second, ensures high statistical security of measurement results in short analysis time.


Due to the equipment’s range, particle size analysis can be performed on a wide range of food products from very fine powders to larger objects such as cereal grains.


Te flexibility of the system allows rapid analysis of a range of samples with the modular system allowing


quick swaps between different types of analysis.


Large particles can be dispersed using a vibratory feeder and gravity disperser allowing particles to be imaged with little or no overlap, whereas small particles can be dispersed under a compressed air system where a short exposure time provides clear images from particles travelling at high speeds.


Te pressure used in the system can be adjusted for agglomerates in order to look at the whole particle or, by introducing more energy, breaking it up into its component parts.


In contrast to other approaches, the particles are not biased by the orientation in which they are presented.


Liquid emulsions Te analyser also accommodates measurements of particle size in wet systems. Tis not only means that particles suspended in liquids can be measured, but also bubbles and droplets in the liquid are quantifiable. Liquid emulsions and slurries can all be analysed.


Particle shape can be measured by considering two or more measures of particle size and studying the ratio between them.


Tese data provide much more information about the particles’ properties and from this, inferences can be made about the properties of the substance, as different particle shapes can have an impact by, for example, altering the surface area to volume ratio of the particle.


Tis information complements particle size information to provide a lot more detail about the particles in question and allows a better understanding of how the size and shape of the particles contribute to specific qualities in the end product.


Practical applications Tere are a range of practical applications in the food and beverage industry for the accurate analysis


of particle shape and size. In terms of quality control, it is of great importance in assuring consistently safe and high quality food and drink products.


For example, in more complex products, such as ‘three-in-one’ coffee drinks which consist of a number of product ingredients such as coffee granules, milk powder and sugar, which all have different particle shapes and sizes, the analyser can provide invaluable data to help with quality control measures.


It also helps with ingredient specifications in new product development. For example, knowledge of the basic physical properties of sugar is of great importance in determining its usefulness in food formulations and the quality attributes and acceptability of foods containing these components.


Diverse products Among some of the specific uses to which Campden BRI is putting the new particle shape and size analyser is the analysis of products as diverse as wholemeal flour and cream.


Recent research work has involved the analysis of the particle size distributions in brown and wholemeal flour and has highlighted the effectiveness of the analyser at identifying the differences between different flours prepared by different processes.


Potential baking industry applications could be looking at the differences between the sizes of bran particles in different types of flour and identifying which flours might perform best in their process.


Campden BRI research has shown that the analysis of cream samples has significant potential, as fat globule size has a major influence on the functional properties of the cream and therefore the way it can be processed.


Tere is also the capacity to investigate the effect of different


“Dynamic image analysis using a pulsed laser allows fast quantification of particle shape and size distribution.”


Helen Metcalfe, Research Scientist, Campden BRI.


processing regimes on globule size distribution.


Te range and potential applications of the equipment to powders, mixtures, slurries and emulsions is wide and varied - from quality control and ingredient specifications to product development. Campden BRI is also investigating the application of particle shape and size analysis to other non-food applications.


Campden BRI is on hand to offer food manufacturers both large and small, an analytical service to provide a greater understanding of how particle shape and size affects product attributes and performance. In addition, interested parties are invited to approach Campden BRI with ideas for applications for their products and potential exploratory research work.


Helen Metcalfe, Research Scientist, Campden BRI, Chipping Campden,


Gloucestershire, UK. www.campden.co.uk www.scientistlive.com


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52