Biopreservative effects of essential oils in the food industry: oils and nuts, seeds and, seed products

The use of essential oils (EOs) to prevent the spread of foodborne pathogens and promote food shelf life across various spheres of the food processing chain is rapidly becoming popular amidst challenges associated with the use of chemical food additives. While the application knowledge of EOs as an antioxidant, antiinflammatory, antimicrobial, pesticide, and food additive has been properly documented in the literature, gaps still exist in understanding the underlying mechanism of their action on food spoilage and potentially pathogenic microbes. Many bioactive constituents including the volatile secondary compounds vary with the nature of the organic source of EO even though some have been assayed; their antimicrobial validation on an individual basis has not been fully investigated nor their biosynthetic pathways are well established. Although plants, particularly herbs, form the predominant sources of food additives and EOs compared to bacteria algae, and fungi, the potency, concentration composition, and diversity of the active principles vary significantly across plant parts (leaf, seed, flower, bark, and fruits). These notwithstanding, essential oils have also been suspected to impact the release of food nutrients in the digestive tract, normal flora of the gut and intestine for optimal food benefits. Consequently, this study aims to promote a better understanding of the diverse sources from which EOs of food value can be expressed, application trends in food processing, and potential strategies for disarming spoilage, pathogenic, and toxigenic microorganisms, and toxin molecules in food.