Vacuum coating of pelleted feed for broilers: Opportunities and challenges

Post-pellet application of fats and protection of heat sensitive bioactives can be achieved through vacuum coating. This review highlights the use of vacuum coating for delivery of liquid fat or bioactives (i.e., enzymes, vitamins, probiotics, etc.) in pelleted broiler diets. Pre-pellet delivery of fats substantially reduces pellet durability and results in losses in bird performance and customer satisfaction. Vacuum coating can also improve storage life and bioavailability of bioactives sensitive to digestion in upper part of gastrointestinal tract. As for encapsulation, vacuum coating may also offer a means of improving delivery and safe handling of offensive compounds. This technology requires highly durable and porous pellets for effective application. The challenges of this technology are the need to better understand how to improve pellet porosity and increase liquid inclusion while maintaining pellet durability; bearing in mind the increased handling of pellets when they are vacuum coated. The discussion also includes methods for measuring and manipulating the porosity of the pellets to achieve optimum pellet durability and liquid application.