Food processing

Food processing, preservation, and packaging are important activities to prevent food loss, and to increase food palatability, transportability, and shelf life and thereby ensuring sufficient availability of food yearround. Improperly stored food can cause foodborne diseases if consumed and result in revenue loss. An estimated 15% of food produced is lost post-harvest. The different traditional and modern preservation techniques help to maintain food quality and safety during storage.

Processing includes mechanical, chemical, and thermal methods to transform raw ingredients into food or other intermediate products. Processing increases the variety of food products available and makes them more convenient to the consumer. Some commonly used food processing methods are chopping or slicing, mincing, liquefaction, fermentation, emulsification, cooking, mixing, and gasification, such as adding gas to bread or soft drinks.

Various factors, such as contamination by microorganisms, insect infestation, enzyme degradation, physical damage, and chemical changes, such as oxidation, can cause food spoilage. The process of food degradation that eventually leads to spoilage starts immediately after harvest or slaughter due to enzymes in the plant cells and animal tissues, mechanical damage caused during harvesting and post-harvest handling, and presence of bacteria, molds and yeasts. Preservation is the process of handling and treating food to prevent its spoilage by controling the growth of microbes, avoiding oxidation of fats (rancidity), and stopping enzyme activity to maintain the nutritional value, texture, and flavor of the food. Some traditional food preservation methods are drying, heating, cooling, fermenting, pickling, boiling, and adding sugar or salt.

Food storage is an important part of food preservation, as improper storage or transport conditions can adversely affect nutrient content, changes in color, texture, and flavor. Besides avoiding physical damage and contamination, careful control of the storage environment including factors like storage temperature and atmospheric gases (oxygen, carbon dioxide, and ethylene) can extend fresh food storag.

Negative aspects of food processing have arisen with the development of so-called ultra processed foods, which usually contain artificial ingredients to change color, texture, flavor and odor as well as ingredients like preservatives and sweeteners. Many of these products are low in nutrients and fibre but high in sugar (which is one of the cheapest preservatives), salt, and fat and therefore calorie-dense. They are pleasant to eat and often lead to overconsumption and obesity. A five-year study of over 100,000 people found that every 10 % increase in consumption of ultra processed food was associated with a 12 % higher risk for cancer.