Amit et al. Agric & Food Secur (2017) 6:51 DOI 10.1186/s40066-017-0130-8 Agriculture & Food Security REVIEW Open Access A review on mechanisms and commercial aspects of food preservation and processing Sadat Kamal Amit†, Md. Mezbah Uddin†, Rizwanur Rahman, S. M. Rezwanul Islam and Mohidus Samad Khan* Abstract Food preservation involves diferent food processing steps to maintain food quality at a desired level so that maxi- mum benefts and nutrition values can be achieved. Food preservation methods include growing, harvesting, processing, packaging, and distribution of foods. The key objectives of food preservation are to overcome inappropri- ate planning in agriculture, to produce value-added products, and to provide variation in diet. Food spoilage could be caused by a wide range of chemical and biochemical reactions. To impede chemical and microbial deterioration of foods, conventional and primitive techniques of preserving foods like drying, chilling, freezing, and pasteurization have been fostered. In recent years, the techniques to combat these spoilages are becoming sophisticated and have gradually altered to a highly interdisciplinary science. Highly advanced technologies like irradiation, high-pressure technology, and hurdle technology are used to preserve food items. This review article presents and discusses the mechanisms, application conditions, and advantages and disadvantages of diferent food preservation techniques. This article also presents diferent food categories and elucidates diferent physical, chemical, and microbial factors responsible for food spoilage. Furthermore, the market economy of preserved and processed foods has been ana- lyzed in this article. Keywords: Food category, Food spoilage, Food preservation, Food processing, Global market Background increase its shelf life retaining original nutritional values, Foods are organic substances which are consumed for color, texture, and favor. nutritional purposes. Foods are plant or animal ori- Te history of ‘Food Preservation’ dates back to ancient gin and contain moisture, protein, lipid, carbohydrate, civilization when the primitive troupe frst felt the neces- minerals, and other organic substances. Foods undergo sity for preserving food after hunting a big animal, which spoilage due to microbial, chemical, or physical actions. could not be able to eat at a time. Knowing the techniques Nutritional values, color, texture, and edibility of foods of preserving foods was the frst and most important step are susceptible to spoilage [1]. Terefore, foods are toward establishing civilization. Diferent cultures at dif- required to be preserved to retain their quality for longer ferent times and locations used almost the similar basic period of time. Food preservation is defned as the pro- techniques to preserve food items [2]. cesses or techniques undertaken in order to maintain Conventional food preservation techniques like drying, internal and external factors which may cause food spoil- freezing, chilling, pasteurization, and chemical preser- age. Te principal objective of food preservation is to vation are being used comprehensively throughout the world. Scientifc advancements and progresses are con- tributing to the evolution of existing technologies and *Correspondence: [email protected] innovation of the new ones, such as irradiation, high- †Sadat Kamal Amit and Md. Mezbah Uddin contributed pressure technology, and hurdle technology [3–5]. Te equally to this work Department of Chemical Engineering, Bangladesh University processing of food preservation has become highly inter- of Engineering and Technology (BUET), Dhaka 1000, Bangladesh disciplinary since it includes stages related to growing, © The Author(s) 2017. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Amit et al. Agric & Food Secur (2017) 6:51 Page 2 of 22 harvesting, processing, packaging, and distribution of categories of foods, components of food spoilage mech- foods. Terefore, an integrated approach would be useful anisms, food preserving and processing methods, and to preserve food items during food production and pro- global market analysis of preserved foods. Tis review cessing stages. ofers the researchers, technologists, and industry man- At present, the global market of the processed food agements a comprehensive understanding that could be items is about 7 trillion dollars, which is gradually grow- highly useful to develop efective and integrated food ing with time [6]. Rapid globalization and industrializa- preservative methods and to ensure food safety. tion are the major contributing factors for the progress of food processing industries in diferent countries. An Classifcation of foods analysis of the UNIDO Industrial Statistics Database Foods can be broadly classifed according to the shelf life, (2005) shows that food processing in developing coun- functions and nutrient value, and processing mecha- tries is an auspicious component of the manufacturing nisms (Fig. 2). Diferent categories of foods are summarized sector, and the contribution of food processing industries in Table 1 and briefy discussed in the following sections. to the national GDP increases with country’s national income [7, 8]. Food categories based on shelf life Tis review paper presents the classifcation of food Food spoilage is a natural process; through this process, items and discusses diferent physical, chemical, and bio- food gradually loses its color, texture, favor, nutritional logical factors of food spoilage. Te basics and advance- qualities, and edibility. Consumption of spoiled food can ments of diferent trivial and modern food preservation lead to illness and in the extreme situation to death [9]. techniques, which are attributed to impede food spoil- Considering the self life, food items can be classifed as age and to yield longer shelf life, are discussed here along perishable, semi-perishable, and non-perishable [10]. with their mechanisms, application conditions, advan- Perishable Foods that have shelf life ranging from sev- tages, and disadvantages. Tis article also reports the eral days to about three weeks are known as perishable. global market trend of preserved and processed food. Milk and dairy products, meats, poultry, eggs, and sea- Figure 1 summarizes a fow diagram showing various food are the examples of perishable food items. If special Based on Shelf Life Classificaon of Based on Funcons Foods and Nutrients Based on Extent and Purpose of Processing Stakeholder: Researchers, Technologists, Food Physical Spoilage Processing and Preservaon Industry Food Spoilage Mechanism and Microbial Spoilage Management, Traders and Mechanism Commercial Aspect Consumers of Food Processing and Chemical Spoilage Preservaon Physical Processing Food Preserving and Processing Biological Processing Methods Global Market Chemical Processing Analysis of Preserved Food Fig. 1 Summary of the review on mechanisms and commercial aspects of food preservation and processing Amit et al. Agric & Food Secur (2017) 6:51 Page 3 of 22 Table 1 Classifcation of foods based on functions Perishable and nutrients [13] Sources Based on Shelf Life Semi-perishabe Functions Non-perishable Body building and repairing Milk, meat, fsh, pulses, vegetables, foods and nuts Body Building and Repairing Energy-giving foods Oil, butter, sugar, cereals, dry fruits, Foods and starch foods Regulatory foods Water, raw vegetables, citrus fruits, Energy Giving Foods Based on the basis of and beverages Funcons Protective foods Milk, whole grain cereals, meat, Regulatory Foods vegetables, and fruits f o Nutrients Protecve Foods Carbohydrate-rich foods Rice, wheat, and starchy vegetables Food Protein-rich foods Milk, meat, fsh, egg, and nuts Carbohydrate rich Foods Classificaon Fat-rich foods Oils, butter, and egg yolk Vitamin- and mineral-rich foods Fruits and vegetables Protein rich Foods Based on the basis of Nutrients Fat rich Foods Food categories based on extent and purpose Vitamins & Minerals rich Foods of processing Unprocessed or Minimally Diferent food processing techniques are used by the Processed Foods food industries to turn fresh foods into food products. Based on Extent and Process Culinary or Food Foods can be classifed into three major groups based Purpose of Processing Industry Ingredients on the extent and purpose of food processing [14]: (a) Ultra Processed Food Products unprocessed or minimally processed foods, (b) pro- cessed culinary or food industry ingredients, and (c) Fig. 2 Classifcation of food, recreated from references [9–12] ultra-processed food products. Classifcation of foods based on extent and purpose of processing is presented in Table 2. preservation techniques are not apprehended, food items could be spoiled straight away [10]. Food spoilage: mechanism Semi-perishable Diferent food items can be preserved Food spoilage is the process in which food edibility for long time (about six months) under proper storage reduces. Food spoilage is related to food safety [9]. Te conditions. Tese