Dry cleaning methods are used in chocolate production to avoid the impact of water on chocolate quality and food safety. However, undeclared milk in non-dairy chocolate products is a frequent cause of food recall, possibly due to ineffective cleaning between product lines. A recent study evaluated various dry cleaning methods for removing milk chocolate residue from production equipment.
Dry cleaning methods include manual scraping of accessible surfaces, push‐through with dark chocolate or cocoa butter, and use of mechanical purging systems (pig systems) for pipelines.
In the current study, pilot-scale experiments were conducted to evaluate the effectiveness of dark chocolate push-through, cocoa butter flush, and pig purging treatments in removing residual milk chocolate from valves, pipes and other parts of the production line. A wet cleaning procedure was also evaluated. Dark chocolate samples were collected at various intervals of the pilot-scale operations and analysed for milk concentrations using ELISA.
Results showed that some methods, particularly pigging of pipelines and cocoa butter flushes, are effective at reducing the presence of milk in non-dairy chocolate products. However, in‐plant validation of cleaning protocols should be performed to ensure that they are effective at significantly reducing the risk of allergen cross‐contact for any given production facility.
Other types of dry cleaning methods, such as scraping milk chocolate residue from accessible pieces of equipment, the use of multiple cocoa butter rinses, and a combination of cleaning treatments on preventing or minimising cross‐contact should also be evaluated in full scale manufacturing plants.
Reference: Zhang et al., 2024. Effectiveness of Dry Cleaning Treatments for Removing Milk Chocolate from Valve/Pipe Assemblies and Pilot-scale Chocolate Processing Equipment. Journal of Food Protection. Vol 87 (10). DOI: 10.1016/j.jfp.2024.100346. Open Access.
