Antimicrobials as Feed and Food Additives, their Technological Properties and Perspectives

As awareness and concerns about antibiotic residues in animal products have increased among consumers, the search for alternatives to antibiotic growth promoters has become more critical. In recent decades, efforts have been renewed to identify natural additives for use in the food industry as biopreservatives for fermented foods and in animal feeding as natural growth promoter additives. Essential oils are natural antimicrobials that have been highlighted for their numerous beneficial effects. When essential oils or medicinal plants with multiple modes of action are combined, their preservative properties are enhanced and the risk of antimicrobial resistance is reduced. Due to their ability to modulate gut microbiota, which is strongly related to animal and human wellbeing, essential oils are increasingly recognized as health modulators in addition to their benefits as food preservatives. As antibacterials, antivirals, antifungals, antioxidants, digestive stimulants, immunomodulators, hypolipidemic agents, and heat stress alleviators, essential oils have been utilized in animal feeding for centuries. It has been demonstrated that essential oils can act as a dietary antibiotic replacement without causing side effects. Additionally, essential oils play a role in the preservation of feed in which they are incorporated, as well as the meat that is obtained from animals fed with them. Essential oils not only reduce oxidative damage to the animal in vivo, but they also exert an anti-oxidative influence on feed that is incorporated with them. Researchers exploited essential oils as feed additives after obtaining favorable results as an alternative to antibiotics. The expanding research horizons in essential oils should bring an end to the extensive use of antibiotics as feed additives. Having in mind that the future is now, the role of essential oils as natural growth promoters and immunity enhancers in animal feeding is huge, but still more investigations are needed for the development of this part of the industry. Due to antimicrobial functions in animal and human health, this chapter reviews recent advancements in essential oil research that will contribute to the development of functional foods and feeds.