The use of propolis as a functional food ingredient: A review

Background: Propolis is a resinous product collected by bees from different plant species that contains numerous compounds with biological activity like antibacterial, antioxidant and anti-inflammatory, among others. These properties make propolis the ideal candidate to be used as a functional ingredient in foods, beyond its known use as an additive. Scope and approach: This article provides a review of the latest papers about the chemical composition (especially polyphenols, flavonoids and terpenes), antimicrobial activity and antioxidant properties of propolis as a functional food ingredient. Besides, this article also reviews the newest technologies developed to incorporate propolis in food systems keeping its antioxidant properties and masking its off-flavour. Key findings and conclusions: Despite the differences in the chemical composition of propolis from all over the world, all of them show antioxidant and pharmacological activity making propolis an attractive natural product to be included in foods as a functional ingredient. Many researchers have proposed the use of encapsulation techniques like spray drying, which allows transforming the ethanolic propolis extract into an easily-handled alcohol-free powder appropriate to be incorporated in food systems. The inclusion of propolis in nanoparticles, biopolymers films and sucrose matrix is also promising. Based on the papers reviewed, further studies are needed relating the incorporation of propolis in foodstuffs, the dose at which its antioxidant or biological properties are effective and the sensory properties of the final product.