Ed used a canning process to preserve tomatoes from the harvest.

埃德用一种罐装工艺来保存收获的西红柿。

Increasing mechanization of the canning process, coupled with a huge increase in urban populations across Europe, resulted in a rising demand for canned food.

罐头加工技术的提高，加上城市人口的大幅增加，导致欧洲对罐头食品的需求不断增长。