ReviewDrop impact behavior on food using spray coating: Fundamentals and applications

- Effectiveness of coating depends on controlling both thickness and microstructure.
- Physical properties of the coating highly depend on drop impact behavior.
- Rebound and splash are limiting factors for spray coating application.
- Models can help food engineers to predict drop impact behavior.

Spray coating is among the most commonly used methods to coat foods, especially fruits. To obtain high quality of coated products the properties of the material to be coated, the properties of coating-forming solutions, method of coating, temperature and contact time between food and coating material should be optimized. In spray coating, drops are impacted and may rebound, splash, or deposit cleanly as is desirable. This review discusses the importance of the drop impact behavior on food using spray coating. The main parameters affecting the behavior such as: physico-chemical characteristics of the liquid, velocity of impact, and physical properties of the food are discussed. Models applied to predict different parameters of drop behavior after impact are presented.