Phenolic extracts from solid wastes of the aromatic plant essential oil industry: Potential uses in food applications

Abstract

During the production of essential oils (EOs) at an industrial scale, a large amount of solid waste (SW) rich in phenolics is left, which constitutes a major management challenge for the EO industry. This review aims to discuss recent developments in the valorization of the phenolic extract obtained from SW remaining after aromatic and medicinal plants (AMPs) distillation. Methods of extraction, health benefits and their potential use as food additives or as functional modifiers in packaging systems are explored. Other applications as antimicrobial/antifungal agents are also elaborated. The SW of AMPs has a similar phenolic profile to that of the raw plant material, representing thus a sustainable source for natural phenolics. However, pre-treatment and extraction methods have an impact on the composition and antioxidant potential of SW extracts. Emerging technologies in preparing phenolic extracts excel in time, solvent and energy savings, compared to conventional methods, but still, there are issues related to high equipment cost and implementation. Phenolic extracts from SW could find applications in the food industry due to their antioxidant and antimicrobial properties, but improvements are needed in terms of extraction efficiency and their potential functionality at an industrial scale.

Keywords

• Aromatic plants
• Essential oil distillation
• Solid waste
• Phenolic extract
• Food applications