Why You Should Avoid Water Glassing Eggs For Long-Term Storage

Preservation techniques like pickling vegetables, dry curing fish, and salting meats, are awesome ways to extend the lifespan of fresh foods. In the past, these methods were invaluable for survival when food was scarce during colder months. However, with the rise of modern-day scientific understanding, not all of these techniques are considered safe. Water glassing eggs for long-term storage is one such method that the FDA does not recommend because of the risk of salmonella and botulism that can cause food poisoning.

Water glassing is the process of submerging fresh eggs into an alkaline solution to hinder bacteria from getting inside the shells and prevent moisture from getting out. This solution used to be made with sodium silicate, also known as water glass, but is now more commonly made of powdered pickling lime (or calcium hydroxide). Often stored in jars or containers, these eggs are placed in a cool dark space, ready to be used when needed.

In the past, water glassing allowed homesteaders to preserve a glut of eggs laid by their chickens during the longer summer months (maximum egg production is reached in periods of the year where there are 16 hours of daylight). They could then use the eggs in their cooking during the fall and winter seasons when egg production stops or slows down, guaranteeing that they had a steady supply to get them through the year.

The FDA advises that it is unsafe to water glass eggs for long-term storage for two reasons. Firstly, the inside of the egg could be contaminated with salmonella. The risk of salmonella being present in eggs laid by hens in a smaller flock is also higher than those laid in larger commercial productions.

Secondly, there's a concern that the lime water that the eggs are stored in could become a breeding ground for the bacteria that causes botulism and penetrate the porous shells. Early settlers avoided washing their eggs before water-glassing them to maintain the natural coating on their surface, known as the bloom or cuticle, and opted to wipe them down with a dry cloth. But now, modern science has found that botulism can be present in the soil where chickens are raised, which is why it's vital to wash eggs before any form of preservation.

A safer way to maximize the lifespan of eggs is to freeze dry them (which boosts their shelf life by decades) or dehydrate them at home with a food dehydrator to remove all their moisture. All you have to do is reconstitute the powdered eggs with some liquid before incorporating them into a batter to make baked goods or pouring them into a pan to make omelets and frittatas. Pickling is another useful preservation technique, however, this requires boiling and peeling your eggs first.