Prospects and Challenges of Essential Oils as Natural Food Preservatives - A Review

Food is the prime requirement of all living organisms, including human beings. Storage of food items has become essential for society in order to minimize the time to obtain a particular food as well as to maintain its nutritional quality. The earliest evidence of food preservation can be traced back to post glacial era. Luis Pasteur proved for the first time that microorganisms are associated with foods and are the major cause of food spoilage, during storage. In early days people used heat, boiling, smoking, drying, salting, and other methods for food preservation. A major development in this field was noticed during the 1940s due to the availability of low cost refrigerators and freezers. During the last two to three decades fermentation as a process and fermented foods increased the shelf life of various food items and revolutionized the techniques of food preservation, too. Later on, with the advancement of food science and technology, various modern techniques such as artificial drying, vacuum packaging, irradiation, and chemical preservatives were employed for long-term storage of food. However, these physical and chemical methods have their own limitations and various side effects. Now-a-days consumers are more concerned about the synthetic, harmful chemicals used as preservatives. Hence, human civilization has renewed its interest for use of natural products, more specifically plant products in food preservation. In the present review I try to review the history and development of food preservation techniques over time. The limitations of different modern methods of food preservation are discussed briefly, leading in search of natural compounds as food preservatives. The nature, extraction, chemical composition and various biological properties of essential oils have been elucidated. Plant essential oils with antimicrobial, antioxidant and other properties makes them a suitable candidate for use in food processing as natural food preservatives.