Quick Answers
Homemade mayonnaise can last 3-5 days when properly refrigerated. The shelf life depends on several factors like the quality of the ingredients, storage method, and handling practices. Properly prepared mayo made with fresh eggs, oil, and lemon juice will keep for up to 1 week in the fridge.
What Makes Mayo Spoil Quickly?
Mayonnaise is an emulsion of egg yolks, oil, an acid like vinegar or lemon juice, and seasonings. It provides a nurturing environment for bacteria and can go bad quickly without proper care. Here are some factors that can make homemade mayo spoil rapidly:
Raw Eggs
Raw or undercooked egg yolks used in homemade mayo can harbor Salmonella and other bacteria that multiply rapidly at room temperature. Always use pasteurized eggs when making mayo at home.
Warm Temperatures
Mayonnaise kept at room temperature promotes bacterial growth. The emulsified nature of the condiment prevents the acidic ingredients from slowing bacteria effectively. Refrigeration is vital.
Frequent Temperature Changes
Fluctuating temperatures like repeatedly moving mayo in and out of the fridge can destabilize the emulsion. This separation of ingredients enables faster spoilage. Store mayo in a consistently cool place.
Prolonged Storage
Like any perishable food, mayonnaise will deteriorate in quality and safety over time. Discard homemade mayo stored for over 7-10 days even if refrigerated. Date and monitor batches for freshness.
Poor Sanitation
Introducing bacteria through unclean utensils, containers, hands, etc. during mayo prep gives microbes an early start. Maintain proper hygiene and carefully sanitize equipment when making homemade mayo.
How to Tell if Mayo is Bad?
Here are some common signs that indicate your homemade mayo has spoiled and should be discarded:
Change in Texture
Fresh mayo has a creamy, smooth consistency. If it becomes excessively runny, watery, lumpy, or greasy, it has likely spoiled. Properly emulsified mayo has a thick texture.
Discoloration
The color of homemade mayo made with egg yolks is rich yellow. Graying, darkening, or unnatural hues like green or blue indicate spoilage.
Sour Smell
Properly made and stored mayo has a mild eggy smell. A pungent, unpleasant, or rotten odor is a clear giveaway of spoilage.
Mold
The appearance of mold, even in spots, means homemade mayo has spoiled and become unsafe. Discard the entire batch if you notice fuzzy growth.
Bubbles
Small bubbles throughout the mayo could signal fermentation and bacterial growth. If the mayo is foamy, effervescent, or fizzy, it has gone bad.
How Long Does Refrigerated Mayo Last?
Properly stored homemade mayo made with fresh ingredients keeps well in the refrigerator for up to 1 week. Here are some tips for maximizing fridge life:
Use Quality Ingredients
Make mayo with the freshest eggs, lemon juice, vinegar, oil, and other ingredients you can find. Avoid old or questionable items.
Store in Airtight Container
Transfer homemade mayo to an airtight container, mason jar, or squeeze bottle to prevent contamination, spills, and air exposure.
Minimize Air Pockets
If storing mayo in a jar, smooth the top and eliminate any air bubbles before sealing to remove oxygen. Oxygen can accelerate spoilage.
Keep Refrigerated
Refrigerate mayo immediately after making, and keep it stored at 40°F or below. Do not leave it out on the counter.
Practice Proper Handling
Use clean utensils and containers. Limit introducing bacteria from dirty hands, surfaces, etc. that can institute spoilage.
Does Mayo Need to be Refrigerated?
Refrigeration is mandatory for maximizing the shelf life and safety of homemade mayonnaise. Leaving mayo out at room temperature for over 2 hours provides an environment for rapid bacterial growth. Below are some key reasons mayo requires refrigeration:
Raw Egg Risk
The raw or undercooked egg yolks in homemade mayo can contain Salmonella and other bacteria that thrive at warm, ambient temperatures. Refrigeration inhibits proliferation.
Ideal Bacteria Environment
The high moisture content and near-neutral pH of mayonnaise make it optimal for bacterial multiplication when left out. Refrigeration prevents this rapid growth.
Lack of Preservatives
Store-bought mayo contains preservatives to control bacteria and prolong shelf life. Homemade versions lack these additives and rely solely on refrigeration.
Prone to Separation
Sitting out at room temperature can cause the emulsified ingredients in mayo to break down and separate quicker. Refrigeration maintains emulsion stability.
Food Safety Standards
The FDA Food Code states that mayonnaise is a time/temperature control for safety food that must be kept refrigerated. Proper food safety demands refrigeration.
Can You Freeze Mayo?
While freezing is not ideal, homemade mayonnaise can be frozen and thawed for later use. Here are some guidelines:
Store in Airtight Container
Transfer mayo to a freezer-safe container leaving 1⁄2 inch headspace. Smooth top, seal lid, label, and freeze. Avoid repeated freezer burn.
Maximize Freshness First
Freeze freshly made mayo at peak quality. Use within 3-5 days refrigerated, then freeze remainder. Avoid freezing older or spoiled mayo.
Thaw Properly in Fridge
Thaw frozen mayo gradually in the refrigerator overnight or during the day. Do not thaw at room temperature.
Use Thawed within 3-4 Days
Once thawed, use homemade mayo within 3-4 days for best quality and food safety. Do not refreeze thawed mayonnaise.
Expect Texture Changes
Freezing can cause separation and changes in the emulsion of homemade mayo. Expect a thinner, looser texture after thawing.
Can You Make Mayo Ahead and Freeze It?
It is possible to prepare a batch of homemade mayonnaise in advance specifically for freezing storage:
Use Ultra-Fresh Ingredients
Make sure all eggs, lemon juice, oil, vinegar, and seasonings are optimally fresh for maximum quality.
Ensure Proper Emulsification
Take extra care to properly emulsify the mayo. Use fresh eggs and emulsion aids like mustard or salt to prevent separation issues after thawing.
Freeze Immediately
Transfer freshly made mayo directly into freezer containers. Freeze right away to seal in freshness. Avoid holding refrigerated first.
Portion for Convenience
Divide mayo into small containers rather than one large batch. This allows for easy thawing of just what you need when you need it.
Label with Dates
Clearly label each frozen mayo container with the date prepared. Track for optimal use within 4 months for best quality.
Thaw Fully Before Using
Make sure thawed mayo has regained its creamy, smooth emulsion and consistency prior to use.
Conclusion
When properly prepared and stored, homemade mayonnaise can keep for up to 1 week refrigerated. For maximum food safety and quality, use the freshest ingredients possible and refrigerate immediately in an airtight container. While freezing is an option, frozen storage can negatively impact texture. With proper handling and care however, homemade mayo can retain its delicious fresh flavor for days. Just remember to rely on visual and sensory clues like smell, texture, and appearance to determine if your homemade mayo has spoiled and needs to be discarded. With the right techniques, you can safely whip up tasty homemade mayonnaise to keep readily available for 7-10 days in the fridge.