PETE plastic bottles are good containers that can be used for storage of shelf-stable, bulk dry foods that you normally keep in canisters in your pantry. Normal kitchen canisters do not have air tight seals. As a result, with changes in atmospheric pressure, air and moisture are pumped in and out of the products causing them to become stale more quickly.
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.
Step 1: Choose which types of bulk dry products you want to store
Decide on the types of products that you are going to store in PETE bottles using oxygen absorbers. These bulk items need to be dry, about 10% moisture or less and low in oil content.
Examples of suitable products are:
Grains : Oats, White Rice, Wheat, and Corn
Milled Grain Products : White Flour, Degermed Corn Meal, and Rice Flour.
Legumes : Beans, Split Peas, and Lentils
Nonfat Dry Milk: Regular and Instant
Dehydrated Fruits and Vegetables : Apples, Carrots, Onions, and Potatoes (Must be dry enough, both inside and out to snap when bent)
(Note: Bulk dry food suppliers should be able to tell you the moisture content of their products)
Examples of products that are not suitable in this type of storage are items that have high or exposed oil content, high moisture or contain leavening. Most of these foods are kept in their original containers and rotated frequently Storage time can be increased by storing them in freezer bags, in the freezer:
Oily or Moist Grains and Milled Grain Products : Brown Rice, Whole Grain Flours and Cereals, Granola etc.
Products containing leavening : Cake/pancake mixes, Biscuit mixes, etc. In the grocery stores these products are package in breathable packages that allow the gas produced by the leavenings to escape.
Home Dehydrated Fruits and Vegetables This is "reduced oxygen packaging". If moist foods, such as inadequately dried vegetables are stored this way, it could result in a botulism poisoning risk. If you have any question about the storability of a given product, contact your local County Agriculture Extension Service office.
Step 2: Start saving, washing, and drying bottles
Start saving bottles Each time you empty a PETE soda or juice bottle, wash it out, drain it, and allow it to dry out completely, For this purpose, save only bottles that have been used for food or water.
Used wide mouth PETE jars that contained items like peanut butter, mayonnaise, and nuts can also be serve as canisters. However they may not be airtight enough to use with oxygen absorbers. The remnants of the original foil seal from the jar rim can limit their ability to provide an adequate seal. You can test the seal by tightening the lid on an empty bottle, placing it under water and squeezing on it to see if any bubbles come out.
The photo below demonstrates how oxygen absorbers work. Air is about 20% oxygen and 80% nitrogen. Nitrogen does not harm food or promote insect growth and does not need to be removed. Oxygen absorbers reduce the amount of oxygen in the container to less than 1%. This results in a lower oxygen content than can be accomplished with vacuum packaging.
The sealed bottle has one AGELESS 300 oxygen absorber and a few drops of water for this demonstration. This is how it looks after one week. It shows that the bottle volume was reduced by about 20%, as the oxygen was absorbed. Do not add water with bulk dry foods when packaging. The products already have adequate moisture to activate the absorber.
Step 3: Obtain oxygen absorbers
Obtain Oxygen Absorbers To find oxygen absorbers, you can check in the yellow pages for "packaging" suppliers or search online for "oxygen absorbers". The type of oxygen absorbers I have used for over 10 years are the AGELESS 300 absorbers from Mitsubishi Gas Chemical Co. This type of oxygen absorber comes in sealed bags of 100 absorber packets each. The 300cc size, with its reserve capacity, is adequate for PETE bottles up to 1 gallon capacity, regardless of the density of the dry foods stored.
Once you are ready to use your absorbers, you will want to open the bag and place the absorbers into glass pint canning jars. One pint jar will hold 25 absorbers, as shown below. Other sizes of jars may be used, but they need to be clean glass jars with metal gasketed lids. They do not have to be new, but must have an airtight seal.
Step 4: Package bulk dry foods in bottles
Verify that the bottles are completely clean and dry before filling.
Set up the packaging area. Once you know how many bottles you are going to fill in the next 20 minutes, remove that many absorbers from your absorber supply jar, spread them out on a tray and reseal the supply jar lid.
Place an oxygen absorber into the bottom of the bottle. The absorber will work regardless of its location in the bottle. However placing it on the bottom allows for full use of its reserve capacity, once you start using out of and reclosing the bottle.
Fill the bottle . As you are filling, tap the bottle several times on the table to settle the product. Fill it all of the way to the top. The funnel shown was made from a water bottle. For products like rolled oats and beans, I prefer to use a piece of light weight cardboard formed into an open sided chute. If you were to cut a tapered 12 oz cup in half lengthwise, then remove the remaining portion of the bottom, this is about what the chute looks like. I make mine out of cardboard cut from the side of a cereal box. I form it into a "U" shape then hold it with one hand onto the mouth of the bottle. I use the other hand to pour the product out of a plastic cup into the chute and down into the bottle. Experiment with the disign and you will find what works best for you. When filling a bottle, I stand it in my wife's large stainless steel bowl, to catch the overflow. (not shown in this picturre)
Wipe off the top rim of the bottle.
Verify that the lid is clean and dry.
Tighten the lid down firmly to reseal, just like you would reseal a bottle of soda.
Label the bottle with the packaging date and, where applicable, ingredients and recipe
You may want to tape around the lid with a narrow strip of duct tape. Taping will not make up for a poor lid seal, but it can help prevent others from opening the bottle until you are ready to use the food. White duct tape or metal foil duct tape work well for this purpose.
Step 5: Storage of PETE bottles of bulk dry foods
Store bottles in a cool, dry location, away from light and heat. Fruit boxes from the grocery store are very good containers to store the filled bottles.
The photo below shows bottles of white wheat stored in a used apple box.
Step 6: PETE bottle storage Information Resources
The followng are links to other reference sources for PETE bottle storage and general infomation on bulk dry storage.
Brigham Young University
Utah State University Extension Service
Step 7: 2nd Page of PETE bottle test
This test demonstrates the capacity of PETE bottles, with oxygen absorbers, to keep a low enough oxygen content to kill insects in all forms.
The low oxygen content does not reduce, but rather helps preserve the ability of the dry grains to germinate when planted or sprouted after storage.