Prudent Food Storage

The wise store up choice food and olive oil, but fools gulp theirs down. - Proverbs 21:20

Section 3 Specific Equipment Questions
A. Storage Containers



A.2 PLASTIC PACKAGING

Before we can discuss plastic packaging it is necessary to understand what is the substance we call "plastic." Plastics are produced from basic polymers called "resins", each of which have differing physical properties. Additives may be blended in for color or to modify particular properties such as moldability, structural rigidity, resistance to light or heat or oxidation. Additionally, it is common for several different kinds of plastic to be laminated together each performing a particular desired task. One might offer structural rigidity and the other might be more impermeable to the transfer of gasses and odors. When bonded together a rigid, gas impermeable package can be made.


Whether that package is safe for food use will depend on the exact nature of the additives blended into the plastic. Some of them, notably plasticizers and dyes, can migrate from the packaging material into the food it's containing. This may be exacerbated by the food it's in contact with especially if it is high in fat, strongly acidic, or alcoholic in nature. Time and temperature may also play a prominent role in the migration of plastic additives into food. For this reason, the (US) FDA assesses the safety of packaging materials for food contact and conducts toxicological studies to establish safety standards. Only plastics that are FDA approved for a particular food type should be used for direct contact with that food.


Being FDA approved, however, may not be all of the story. It must still be determined whether the particular plastic in question has the physical properties that would make it desirable for your purpose.


As mentioned above each base resin has somewhat differing physical properties that may be modified with additives or combined by laminating with another plastic or even completely unrelated materials such as metal foils. An example of this is "Mylar", a type of polyester film. By itself, it has moderate barrier resistance to moisture and oxygen. When laminated together with aluminum foil it has very high resistance and makes an excellent material for creating long term food storage packaging. One or more other kinds of plastic with low melting points and good flow characteristics are typically bonded on the opposite side of the foil to act as a sealant ply so that the aluminized Mylar can be fashioned into bags or sealed across container openings. The combined materials have properties that make them useful for long term storage that each separately do not have.


The most common plastic that raises suitability questions is High Density PolyEthylene (HDPE). It's used in a wide array of packaging and is the material from which most plastic five and six gallon buckets are made. It has a moderate rigidity, a good resistance to fats, oils, moisture and impacts, a fair resistance to acids, but is a relatively poor barrier to oxygen.


Whether it is suitable for your purpose depends on how sensitive to oxygen your product is and how long you need it to stay in optimal condition. Foods such as whole grains are not particularly delicate in nature and will easily keep for years in nothing more than a tightly sealed HDPE bucket. Most legumes are the same way, but those that have high fat contents such as peanuts and soybeans are more sensitive to O2. Other foods such as dry milk powder might only go a year before deleterious changes are noticed. If that milk were sealed in an air-tight aluminized Mylar bag with the oxygen inside removed, the milk would keep for much longer. Better still would be to seal the milk in a metal can or glass jar. HDPE alone can be used for long term storage with one or more of the following precautions to keep a high food quality: The food should either be put on a shorter rotation cycle than packaging also using a second gas barrier such as Mylar; be periodically opened and re-purged or fresh absorbers should be inserted.


Another common plastic used in food storage is polyethylene terephthalate commonly known as PETE or PET plastic. Used to make soda, juice, and some water bottles among other products it is available for recycling into food storage containers in nearly every home. Properly cleaned and with intact screw-on lids PETE plastic containers will serve for keeping nearly any kind of food providing the containers are stored in a dark location. PETE has good barrier properties against oxygen and moisture and when used in combination with oxygen absorbers presents a complete dry-pack canning system in itself. About the only drawbacks to PETE plastics are that they are nearly always transparent to light, container volumes typically are limited to a gallon or less, and when used in conjunction with oxygen absorbers the sides will flex sufficiently to make stacking difficult though you could simply lay them on their sides.


There are other plastics and plastic laminates with good oxygen and moisture barrier properties that are suited for long term food storage, but they are not as easy to find, though some used containers might be available for reuse.


A.2.1 HOW DO I GET THE ODOR OUT OF PICKLE BUCKETS?

I've had fairly good luck doing it in the following way. As vinegar is the primary smell in pickles and it's acidic in nature, we use a base to counteract it. First we scrubbed the bucket well, inside and out, with dish detergent, most any sort will do. Then we filled the buckets with hot water and dissolved a cup of baking soda in each. Stir well, get the bucket as full as you can and put the top on. Put the bucket in the sun to keep it warm so the plastic pores stay open as much as possible. In a couple of days come back and empty the buckets. Rinse them out, fill with warm water again and add about a cup of bleach and reseal. Put back in the sun for another couple of days. Empty out and let dry with the tops off. We completely eliminated the vinegar smell this way. It might be possible to cut the time down a lot, but we haven't experimented that much.




Updated: 9/18/96; 4/16/97; 7/21/97; 10/20/97; 9/15/98; 11/02/99; 12/01/03


Copyright © 1996, 1997, 1998, 1999, 2003. Alan T. Hagan. All rights reserved.


Excluding contributions attributed to specific individuals or organizations all material in this work is copyrighted to Alan T. Hagan with all rights reserved. This work may be copied and distributed for free as long as the entire text, mine and the contributor's names and this copyright notice remain intact, unless my prior express permission has been obtained. This FAQ may not be distributed for financial gain, included in commercial collections or compilations, or included as a part of the content of any web site without prior, express permission from the author.


DISCLAIMER: Safe and effective food storage requires attention to detail, proper equipment and ingredients. The author makes no warranties and assumes no responsibility for errors or omissions in this text, or damages resulting from the use or misuse of information contained herein. This FAQ is not intended for, nor should it be used in, any commercial food applications.


Placement of or access to this work on this or any other site does not necessarily mean the author espouses or adopts any political, philosophical or metaphysical concepts that may also be expressed wherever this work appears.



Table of Contents


Acknowledgements & Foreword


Section 1 - Shelf Lives


  1. Time, Temperature, Moisture, Oxygen and Light

Section 2 - Foods


  1. Common Storage Foods

A. Grains & legumes


  1. Grains & Grain Products
  2. Legumes
  3. Availability of Grains and Legumes
  4. Storing Grains and Legumes

B. Dairy Products


  1. Dry Milks
  2. Canned Fluid Milks and Creams
  3. Butter
  4. Cheese

C. Eggs


  1. Dry Eggs

D. Sugar, Honey and Other Sweeteners


  1. Granulated Sugars
  2. Honey
  3. Cane Syrups
  4. Corn Syrup
  5. Maple Syrup

E. Fats and Oils


  1. Buying & Storing Oils and Fats
  2. Extending Shelf Life By Adding Anti-Oxidants

F. Cooking Adjuncts


  1. Baking Powder
  2. Baking Soda
  3. Herbs & Spices
  4. Salt
  5. Vinegar
  6. Yeast

G. Infant Formula


  1. Alternatives to Breastfeeding
  2. Selecting and Feeding An Infant Formula
  3. Storing Infant Formulas and Baby Foods

H. MREs - Meals, Ready to Eat


  1. U.S. Military MREs
  2. U.S. Civilian MREs
  3. British/Canadian MREs
  4. Other Self-Heating Ready To Eat Type Products

I. Ration Bars


  1. Ration Bars

Section 3 - Specific Equipment Questions


A. Storage Containers


  1. What is Food Grade Packaging?
  2. Plastic Packaging
  3. Metal Cans
  4. Glass Jars
  5. Mylar Bags
  6. Reusing or Recycling Packaging

B. CO2 and Nitrogen


  1. Dry Ice
  2. Compressed Nitrogen

C. Vacuum Sealing


  1. Vacuum Sealing Considerations

D. Freeze Treating


  1. Freeze Treating

E. Oxygen Absorbers


  1. What Is an Oxygen Absorber?
  2. How Are Oxygen Absorbers Used?

F. Moisture in Packaging and Food Storage


  1. Why Moisture is Important
  2. What Is A Desiccant?
  3. Types of Desiccants
  4. How Do I Use Desiccants?
  5. Where Do I Find Desiccants?

G. Diatomaceous Earth


  1. What is Diatomaceous Earth?
  2. Where Do I Find DE and What Type Should I Buy?
  3. How Do I Use DE in Food Storage?

Section 4 - Spoilage


A. Insect Infestations


  1. Pests of Stored Grains, Legumes and Dry Foodstuffs
  2. Control of Insect Infestations

B. Molds in Foods


  1. Minimizing Molds
  2. Molds in Canned Goods
  3. Molds in Grains and Legumes

C. Bacterial Spoilage


  1. Botulism

D. Enzymatic Action in Food Spoilage


  1. Enzymatic Action

Section 5 - Shelf Lives


A. Food Product Dates


  1. "Best Used By", "Use By" and Other Food Product Dates

B. Closed Dating


  1. Closed Dating Codes Used by Some Food Manufacturers

C. Shelf Lives


  1. Shelf Lives of Some Common Storage Foods

Section 6 - Resources


A. Books


  1. Books

B. Pamphlets


  1. Pamphlets

C. Electronic-online


  1. Information sources
  2. Software sources

D. Organizations


  1. The Church of Jesus Christ of Latter Day Saints - LDS Family Cannery Guidelines

E. Food and Equipment Suppliers


  1. Mail Ordering Storage Foods What You Should Know
  2. Addresses of Suppliers

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