Packaged foods are manufactured outside the home for purchase. This can be as simple as a butcher preparing meat, or as complex as a modern international food industry. Early food processing techniques were limited by available food preservation, packaging and transportation. This mainly involved salting, curing, curdling, drying, pickling, fermentation and smoking.[27] Food manufacturing arose during the industrial revolution in the 19th century.[28] This development took advantage of new mass markets and emerging new technology, such as milling, preservation, packaging and labeling and transportation. It brought the advantages of pre-prepared time saving food to the bulk of ordinary people who did not employ domestic servants.[29]

At the start of the 21st century, a two-tier structure has arisen, with a few international food processing giants controlling a wide range of well-known food brands. There also exists a wide array of small local or national food processing companies.[30] Advanced technologies have also come to change food manufacture. Computer-based control systems, sophisticated processing and packaging methods, and logistics and distribution advances, can enhance product quality, improve food safety, and reduce costs.[29]

Commercial trade