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Tempering of Chocolate in a Scraped Surface Heat Exchanger |
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| Authors: | C LOISEL G KELLER G LECQ B LAUNAY M OLLIVON |
| Affiliation: | Authors Loisel and Lecq are with Centre Jean Thèves, groupe DANONE Branche Biscuits, 6 rue Edouard Vaillant, BP 16, 91207 Athis-Mons Cedex, France. Authors Loisel, Keller and Ollivon are affiliated with Laboratoire de Physico-Chimie des Systèmes Polyphasés, CNRS URA 1218, UniversitéParis-Sud, 92296 Châtenay-Malabry, France. Author Launay is with Laboratoire de Biophysique de L'Ecole Nationale Supérieure des Industries Agricoles et Alimentaires, 1 avenue des Olympiades, 91305 Massy Cedex, France. Address inquiries to Dr. C. Loisel. |
| Abstract: | Crystallization of dark chocolate during different tempering processes has been studied in-situ in a lab-scale Scraped Surface Heat Exchanger. The linear relationship between torque and viscosity made possible the control of chocolate crystallization during tempering by following torque variations vs. time and converting them to equivalent viscosity values. These variations of equivalent viscosity of chocolate observed during tempering were correlated with temper-meter measurements which had been related to the content of cocoa butter seeding crystals. A temperature cycle (50-26.1-30.5-33.3°C) enabled preparation of a well-tempered chocolate stable for ≥30 min at that temperature. It was characterized by a seed crystals content of about 1.15 ± 0.1% of cocoa butter, crystallization temperature of 23.9 ± 0.2°C in the temper-meter and an equivalent viscosity of 3.0 ± 0.4 Pa.s. |
| Keywords: | kinetics scraped-surface heat exchanger chocolate crystallization |