Abstract—Spoilage occurs in plant produce due to the action of field and storage microorganisms. The conditions of storage can also cause physiological spoilage. Various methods exist to ensure that these food substances maintain their quality long after harvesting. However, many of these methods either fail to keep the plant for the required period or predispose the plant to other spoilage risks. The major shortcoming posed by the use of many antimicrobials is the chemical residues it deposits in the food substance. The use of plants in preservation has been in use for a long period, though little understood then, it served its purposes. A better understanding of the roles of these plant parts in increasing the shelf life of farm produce has helped in the creation of more effective and safer means of pest and microbial control. This can be extended to plants that have not been used for these purposes initially. Microbial sources should also be investigated as these have provided cheaper sources of secondary metabolites. Keywords—Antimicrobials, Food preservation, Phytochemicals. I. INTRODUCTION HE availability of farm produce during off-season has been plagued majorly by problems associated with preservation and storage. Of the many hazards that plague food handling and storage, spoilage caused by microbial contamination or physiological activities occurring in the food product itself [1] contribute significantly to food loss. A large portion, (30% - 50%) of these products is lost in postharvest processes leading to an inability to access enough of these products at all times despite the annual increase in production. Humidity alone or in combination with temperature also plays substantial role in the physical hazards that pose threat to food security. The presence of some amount of moisture or water activity in some food substances, especially dried raw food materials and processed foods will favor the growth of bacteria and enhance fungal infestation. The presence of these organisms usually leads to rotting, discolouration and formation of off-flavors in the food products depending on the types of microorganisms and their corresponding physiological activities. Mechanical hazards arising from bruises, compression and impact force during harvesting, transportation from the farm and storage methods are implicated in the initiation of physical hazard due to exposure to atmospheric milieu; chemical and biochemical hazards resulting from interplay between oxygen and activities of endogeneous enzymes. Approaches to ensure prolonged storage hence availability of farm produce by reduction of microbial spoilage are reviewed accordingly. Oladotun Fatoki is with The Polytechnic, Ibadan, Nigeria (e-mail: dotfatoki@yahoo.co.uk). II. FOOD PRESERVATION A. Traditional Approaches to Preservation Long before the advent of technology and its attendant applications, man has devised numerous means of preserving his food for availability during off-season and for preservation of quality of the food substances during long storage. One notable preservation method is fermentation. Traditionally, fermentation was carried out spontaneously and besides preservation assisted in food processing. Fermentation procedures enhanced flavor, aroma, digestibility as well as reducing cooking times in food substances. Lactic acid bacteria and yeasts were the major microorganisms involved in these fermentations and the production of acids made the food unbearable for the growth of many spoilage and pathogenic microorganisms. This was applied to the preservation of vegetables where sugars in the leaves were converted to lactic acid [2]. Drying has been applied successfully to many food substances to prolong their shelf life. This seeks to reduce the moisture content which makes the food substances unfavorable for growth of many spoilage bacteria. Smoking is an adaptation of drying since many of the methods used in its adaptation to preserve foods also seek to reduce the water activity in food substances (such as fish) before they are eventually dried. This is in addition to the production of antimicrobial substances from the wood smoke and ash. Drying, however, predisposes the products to mould and insect infestation [3]. Storage of maize husks in cribs and silos is a method that ensured that they remained dry even during the rainy seasons as well as protection from insect infestation [1]. Other methods that also help in longer storage by reducing the microbial population of food substances include subjecting them to high temperatures. This helps in reducing enzyme activity that could cause physiological spoilage [2]. Grains are stored among neem leaves and with capsicum peppers to ensure they are preserved till the next season. Tubers are stored under dried mulches of maize and millet left under a shade, while others are preserved under plant materials mixed with soil [1]. B. Modern Approach to Preservation Proper postharvest handling is being employed in the control of plant losses. This has an effect on the shelf life as well as ensuring the security of plant products in terms of quality and quantity round the year. An important factor that has been identified in ensuring food security is the proper postharvest storage of food crops. The design, construction and maintenance of storage facilities and power supply in some developing countries are factors considered in postharvest storage. Refrigeration to a temperature of about - Oladotun A. Fatoki, Deborah A. Onifade Use of Plant Antimicrobials for Food Preservation T World Academy of Science, Engineering and Technology International Journal of Bioengineering and Life Sciences Vol:7, No:12, 2013 1110 International Scholarly and Scientific Research & Innovation 7(12) 2013 scholar.waset.org/1307-6892/9996635 International Science Index, Bioengineering and Life Sciences Vol:7, No:12, 2013 waset.org/Publication/9996635