How to preserve food for a longer time? Home › Forums › How to preserve food for a longer time? This topic contains 9 replies, has 2 voices, and was last updated by admin 1 year, 5 months ago. Viewing 1 post (of 1 total) Author Posts June 20, 2016 at 8:19 pm #2455 adminKeymaster I am selling lunch boxes, what are the approaches to preserve the food so I can sell it on the next day? Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.