Because of their oxygen/moisture barrier qualities, PETE bottles can be used as canisters to better maintain the freshness of stored dry foods. If you want to store these items for a longer time period, the use of oxygen absorbers in the PETE bottles will protect against insect infestation and help preserve quality longer.
In order to kill insects in adult, larva, and egg stages of growth, it is necessary to pull the oxygen content down to below 1% and hold it there for at least two weeks. Most types of plastic bottles are too porous, and leak too much oxygen in, but PETE bottles work well. Soda bottles and most shelf-stable juice bottles are made of PETE. Look at the recycle emblem on the bottom. It should have a #1 in the emblem and the letters PETE or PET below.