Salad Dressing & Mayonnaise Expiry and Shelf Life: A Complete Guide

Understanding Salad Dressing & Mayonnaise Shelf Life

Salad dressings and mayonnaise are kitchen staples across the UK and EU, but their shelf life varies significantly depending on ingredients, preservatives, and storage conditions. Proper understanding helps reduce food waste and ensures safety. According to the UK Food Standards Agency, most opened condiments should be refrigerated and consumed within recommended timeframes to minimise bacterial growth.

How Long Does Salad Dressing Last?

Store-Bought Dressings

Commercially produced salad dressings contain preservatives and acidity regulators that extend their shelf life. Unopened bottles typically last 3 to 6 months when stored in a cool, dark cupboard. Once opened, refrigeration is essential:

• Creamy dressings (e.g., ranch, Caesar, blue cheese): Use within 1 to 2 months after opening.
• Vinaigrettes and oil-based dressings: Can last 2 to 3 months refrigerated due to higher acidity from vinegar or citrus.
• Dressings with alcohol (e.g., some balsamic varieties): May remain safe for up to 4 months when chilled.

Homemade Dressings

Without commercial preservatives, homemade dressings spoil quickly. The UK's Food Standards Agency advises using homemade vinaigrettes within 3 to 5 days and creamy homemade dressings (containing dairy or eggs) within 2 to 3 days. Always label with the preparation date.

Mayonnaise Expiry: What You Need to Know

Mayonnaise is particularly perishable due to its egg yolk and oil content. Unopened jars can last 1 to 2 months past the printed date if stored in a cool pantry (below 25°C). Once opened, refrigeration at 4°C or below is mandatory:

• Commercial mayonnaise: Use within 1 to 2 months after opening.
• Homemade mayonnaise: Consume within 2 to 3 days and never leave at room temperature for more than 1 hour.

The European Food Safety Authority (EFSA) notes that mayonnaise containing pasteurised eggs has a longer shelf life, but refrigeration remains critical. If mayonnaise is left out at a picnic or buffet for over 2 hours, discard it immediately.

How to Tell If Salad Dressing or Mayonnaise Has Gone Bad

Rely on your senses and these clear indicators of spoilage:

• Smell: A sour, rancid, or "off" odour means it's unsafe.
• Texture changes: Separation that doesn't re-emulsify after shaking, or a grainy, lumpy consistency in mayonnaise.
• Mould: Any visible mould on the surface or around the lid—discard the entire container.
• Colour shifts: Darkening, yellowing, or unusual discolouration.

If in doubt, follow the UK Food Standards Agency's principle: "When in doubt, throw it out." Consuming spoiled condiments can cause food poisoning, especially for vulnerable groups like pregnant women, the elderly, or those with weakened immune systems.

Best Storage Practices for Maximum Freshness

Refrigeration Rules

• Always refrigerate after opening, ideally at 4°C or below.
• Store in the main body of the fridge, not the door, where temperatures fluctuate.

Container Hygiene

• Use clean utensils every time you scoop out dressing or mayonnaise to avoid introducing bacteria.
• Transfer homemade dressings to sterilised, airtight glass jars or bottles.

Avoid Contamination

• Never return used dressing to the original container.
• Keep bottles away from heat sources like ovens, hobs, or direct sunlight.

Label and Date

• Write the opening date on store-bought bottles and the preparation date on homemade versions.

Quick Reference: Shelf Life at a Glance

For specific product queries, consult the manufacturer's label or contact their customer service. Always prioritise food safety over extending shelf life—your health is worth more than saving a jar of dressing.