ORIGINAL PAPER Electrospraying and Electrospinning of Chocolate Suspensions C. J. Luo & Shirin Loh & Eleanor Stride & Mohan Edirisinghe Received: 21 October 2010 / Accepted: 3 February 2011 # Springer Science+Business Media, LLC 2011 Abstract Novel applications of efficient and economical techniques such as electrospraying and electrospinning in chocolate processing could be a strategy to help manufac- turers improve declining sales growth rate in a saturated confectionery market. In this study, electrosprayed near- monodisperse particles have been produced using chocolate suspensions. Electrospun fibres have also been created from a commercial chocolate sauce. The effects of process parameters such as sugar concentration, addition of electro- lytes (NaCl), flow rate, applied voltage and collection distance on the production and morphology of as-sprayed chocolate particles were studied. A positive linear trend in the electrosprayed chocolate particle diameter and diameter distribution range with increasing sugar concentration in the chocolate suspension was demonstrated. Sugar concentra- tions of 30 – 35%w/ w resulted in very fine, near- monodisperse chocolate particles. Trace amounts of elec- trolyte at 1%w/w were found to decrease the average particle diameter and improve the monodispersity of the particles produced. The addition of NaCl at low concen- trations increased the electrical conductivity and, to a lesser extent, the surface tension of the chocolate samples. Further increases in NaCl concentration to 3%w/w did not bring any additional decrease in the average diameter of the chocolate particles. In addition, the observed modes of electrospraying and the characteristics of chocolate particles obtained under these were investigated. Bead-on-string morphology was commonly observed among electrospun chocolate fibres. Moreover, satellite particles and very fine fibres were obtained during the transition between electro- spraying and electrospinning. The continuous alternating shape of elongated spheres and thin fibres may have the potential for varying the microtexture of the chocolate products. Keywords Electrospraying . Electrospinning . Chocolate Introduction Chocolate processing is a major sector in the food industry. Over the last 10 years, an average of ∼10 kg per person per annum of chocolate confectionery has been consumed in many western European countries, with Britain being Europe's number one chocolate consumer (Datamonitor 2007). The combined sales of sugar and chocolate confectionery in the UK were more than those of tea, newspapers and bread put together (Beckett 2000). The global confectionery market in 2008 was worth $99.7–127.9 billion, and the chocolate category was the largest confectionery market in terms of value, with more than 50% share in both the EU and USA (Business Insights 2009; Datamonitor 2009, 2010). This makes the chocolate industry a very important one. However, the trend of chocolate consumption has slowed down as health and diet concerns impacted sales. In 2004, chocolate volume sales rose by less than 1% to 605 million kilograms. Sales for chocolate across Europe reached €5.6 billion by 2007, an increase of just 4%. In the UK, the annual growth rate of the confectionery market dropped from 3.1% between 2001 and 2006 (Datamonitor 2008a) to 2.3% between 2002 and 2007 (Datamonitor 2008b). C. J. Luo : S. Loh : E. Stride : M. Edirisinghe (*) Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK e-mail: m.edirisinghe@ucl.ac.uk Food Bioprocess Technol DOI 10.1007/s11947-011-0534-6