Canned (shelf stable) pickled eggs that don't require refrigeration?

Question

Terminology: when I refer to "canned eggs", I'm referring to pickled/marinated eggs that have been processed, and can be stored at room temperature long term (i.e. shelf stable). When I refer to just "pickled eggs", I'm referring to pickled/marinated eggs that have been processed, but require refrigeration.

I've been pickling eggs for years now (eggs plus hot peppers and garlic plus a tiny bit of beet for red coloring), and a neighbor recently gave me a large amount as she can't sell them at the local market for the next several weeks (i.e. hundreds of eggs), so she gave them to me. I'm planning on making several dozen jars of them. I've used the process described by the "Kuntz Family Picked Eggs" article I found online years back, and never had any problems.

However, the page, citing the NCHFP, notes that it's not recommended to attempt canned (i.e. shelf stable and no refrigeration) pickled eggs. It goes on to describe a recipe that should be safe for canned eggs, provided they are kept in a dark, cool location. I've also found a lengthy StackExchange:Cooking discussion that arrives at the same conclusion: canning eggs is a no-go.

I've recently discovered a brand of pickled eggs, "Nanjo's", that is sold at the local grocery stores, and it's' canned pickled eggs (room temperature, no refrigeration). They also taste quite good.

So, is there some trick to making shelf stable pickled eggs that I don't know about (i.e. pressure canning versus just hot water boiling) that makes them guaranteed shelf stable (i.e. by a reputable authority on the subject) and safe to store (i.e. at least for 6 months) without refrigeration? I'm skeptical that such a product could be sold in major stores if it had a serious risk of botulism contamination.

Thank you.

Edit:

I found some posts by the author of the first web site I linked:

• https://www.houzz.com/discussions/1931142/canning-eggs-is-this-safe
• https://www.houzz.com/discussions/1933723/canning-pickled-eggs-can-be-safe

Answer 1

There is an article available here that discusses how shelf stable pickled eggs are made.

https://www.researchgate.net/publication/311743836_Pickling_Eggs

Egg Innovations and Strategies for Improvement: Chapter 38, Pickling Eggs

Jessie Usaga, Oscar Acosta, Elizabeth K. Sullivan and Olga I. Padilla-Zakour

I'm not an expert, but it looks like the hardest part is ensuring that the eggs are acidified enough. You would need a pH meter, periodically recalibrated at 25C, and you would need to blend up some of your pickled eggs with brine (measured to match the ratios in the final product) to make a slurry, bring the temperature of the slurry to 25C (since the pH meter depends on temperature), and the resulting pH must be below a certain value. Probably tested multiple times to account for variations in eggs (yolk ratios, etc.).

You would need to control the process to ensure that it is consistent.

It looks like there are also several laws that regulate the process (at least when done commercially), such as inspections, needing pH measurements to be written in ink, and maintaining records so product can be recalled if there is a food safety issue.

The article also has other considerations such as heat treatment, sanitizing tools and ingredients, and only using eggs that peeled without nicks. Please read the article and sources mentioned there carefully for all the details.

It looks like the process is probably too complicated to be performed properly in a home kitchen or without proper training.