Do You Need to Clean Your Eggs?

Shawn J. Houtsinger

with permission from
SPPA Bulletin, 2012, 17(3):9-10

The traditional and non-traditional methods

Our company receives numerous calls and e-mails on the question of: "Should I be cleaning my eggs?" And our stance is a resounding "yes", but with a slight pause. Why the pause? It isn't, depending upon your situation, that easy to answer. So what is the issue then? Quite simply--the issue lies with contaminated eggs that are covered with bacteria (on the shell) or penetrating into shell.

There are numerous ways to clean an egg: dry cleaning, wet cleaning, rinsing and washing. There are a majority of chicken owners that simply wipe the egg off and put it into storage. However, in the past five years, a rise in Salmonella Enteritidis has caused concern for the FDA, and hence a stricter policy enforcing better regulation on egg control ( Moreover, the process to remove bacteria and kill microbes that remains in 10% of eggs laid and remain present in the egg white or yolk ( However, the new regulations by the FDA and USDA on sanitizing require at least a four step process to eliminate all growth of bacteria. Both include in this process a sanitization method of wet washing and rinsing ( Yet, these stringent regulations apply only to the commercial industry, which leads the backyard grower to local store without any policies to enforce a proper method of sanitization.

It is important to note that the issues with the soap or chemical approach are the implication of the chemical seeping into the egg and contaminating the eggs. Before we move forward, it is important to raise the flag of bias now. We promote and stand by the all-natural use of enzymes to clean eggs.

What are Enzymes and how do they work?

The utilization of enzymes as a cleansing agent within products has been around for the last 40 years. Enzyme cleaners are non-toxic and effective; they clean better than toxic and non-toxic detergents. Enzymes cleaners remove odors by breaking down the materials causing the odor. Consumers use enzymes for stain removal & odor removal, and laundry, carpet and upholstery cleaning. The most commonly used application and manufacture of enzymes is washing agents (detergents); largest use of application in the industry. Consumers don't realize they are actively using enzymes as their washing agent whenever they use a detergent. Or, in other applications, enzymes are used as an auxiliary agent in the manufacturing process within finished products. The introduction of enzymatic formulas within the environmental and agriculture industry has been used for the past two decades. Studies performed at the University of Wisconsin have shown the recontamination, of using chemical vs. enzymes, as a conclusive result that enzymatic cleanser keeps the egg sanitized longer than conventional chemical based products.

"Just the Facts, Ma'am--just the facts."

Now that you understand where our company stands, let's go over just the facts and methodology of chicken laying, collecting and storage.

The process of egg collection extends beyond just the procedure of washing eggs. The gathering, and one commonly overlooked, is the first, and most important, step. Providing a healthy environment for your flock is vital in producing the best eggs. Clean, parasite-free, and ammonia-free environment aides in a heavier, stress-free and more productive chicken. Proper storage of your eggs is necessary to avoid further contamination. You should store the eggs in a refrigerator at a constant temperature of 45 F (7.2 C) ambient temperature if kept for more than 36 hours; eggs are susceptible to changes in temperature, which may result in a loss of quality. You can read more about how to store your eggs from the following links:

What methods are being used to clean eggs?

The current environment of how poultry owners clean their eggs is:
- No cleaning or dry cleaning
- Soap & Water
- Chemicals - chlorine or bleach
- Enzyme based products

Wet Cleaning/Wiping

An egg is covered by a waxy layer (the cuticle) that helps prevent microbes from entering the pores. While the cuticle does provide a great barrier against contaminants, it does not prevent water to penetrate past its shell pore and pose a threat to microbial penetration (Zeidler, 2002). The process of wet cleaning is to allow water to pour over the surface of the egg in a continuous flow that allows the water to drain away, while removing dirt from the surface.

Wet cleaning is prohibited by state regulation for some markets. Specifically, Minnesota regulations prohibit the sale of wet-cleaned eggs to stores. Immersion washing is not condoned and may be prohibited.

Dry cleaning using a brush, sandpaper, or a loofah sponge has fewer issues than wet cleaning, and is recommended for small producers. Or, the process of wiping is using an enzymatic product that cleans the surface of the egg, using natural enzymes, to remove contaminants and reduce the amount of time the egg is saturated with merely water.

If detergents or other additives are used for wet cleaning, they must either be non-synthetic or among the allowed synthetics on the National List at section 205.603 of the National Organic Standard. Synthetics include: chlorine, hydrogen peroxide, ozone and peracetic acid. These serve mostly as sanitizers rather than as washing agents.


Eggs need to be colder than the water they are washed in. Warmer water contracts the shell, tightening it, and providing a barrier. Eggs should be washed in water that is at least 20 degrees F warmer than the warmest eggs, and the water should be at least 90 degrees F. This is to prevent water that is cooler than the egg from forcing the egg contents to contract and pull water and microbes through the shell into the egg and cause contamination. However, the wash water should not be more than 40 degrees F above the temperature of the eggs or the eggs may experience thermal cracking. Washing eggs come with two methods: chemical or natural. The downfall of using a chemical based product with the water is risk of penetration of it past the bloom and into the yolk. However, a non-chemical, more natural approach (enzymes) causes no harm to the surface, bloom or yolk; i.e. taste, smell and quality.

Although the USDA does not condone immersion washing (soaking or standing), a majority of small producers do not have to abide or operate under the legislation.

Who uses these methods?

Organic Farms typically rinse the eggs, if dry cleaning, with water and depend upon the natural sterile process of the chicken to protect its eggs. These are your non-traditional methods and represent less than 20% of chicken owners (FDA, 2009).

Backyard owners are using a soap and water mixture or enzymes based solution. This method is traditional among the majority of chicken owners’ (FDA, 2009).

The commercial industry (store bought) standards for egg cleansing are heavily regulated by FDA and USDA. The process for cleansing eggs is to use a chemical based solution – in the form of chlorine or bleach. This explains why you receive very white (bleached) eggs in the store.


You may be asking yourself--if the commercial industry is regulated by FDA and USDA, then who overlooks the organic, backyard and local stores? The USDA will do random blue light testing to ensure eggs are contaminant free and abide by all safety standards. The blue light, when passed over a contaminated egg, will glow--this glow is the bacteria. If contamination is found, your entire stock may be pulled by the inspector.


The primary USDA egg grades are AA, A, and B. Grades are based on both exterior and interior quality. For specifics on egg grading, see the USDA-AMS Poultry Programs web site.

Grading also involves sorting eggs into weight classes or sizes (peewee, small, medium, large, extra-large and jumbo). The USDA Egg Grading Manual details what an egg of a specific class needs to weigh. Many producers do not grade but mark their eggs as mixed, unclassified, or ungraded. Farm-scale equipment for grading is available through farm supply outlets such as NASCO.


Eggs may be carton-packed according to size or as unsized. Standard packaging for direct sale is by the dozen, half-dozen, or dozen-and-a-half. Cartons are typically made of pulp paper, Styrofoam or clear plastic.


Eggs packed under federal regulations require the pack date to be displayed on the carton. It is a three digit Julian date that represents the consecutive day of the year. The carton is also dated with the 'Sell-by' or expiration date, which depends on the state requirements. Eggs with a federal grade must be sold within 30 days from day of pack.

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