Key findings
- 1Homemade mayonnaise (egg yolk, oil, acid, salt) is a short list of recognizable ingredients and takes a few minutes to make
- 2In our analysis, mayonnaise averages a Processing Score of 6.0, which is Level 3
- 3EDTA, the preservative in commercial mayo, is the same chelating compound used in industrial water treatment and medical heavy-metal detoxification
- 4"Light" mayonnaise is typically more processed than regular; it replaces fat with water, modified food starch, and additional emulsifiers to maintain texture
Why is Mayonnaise Level 3 on average?
Mayonnaise is fundamentally an emulsion; oil droplets suspended in water (from egg yolk and acid) stabilized by lecithin naturally present in the yolk. Homemade mayo requires just egg yolk, oil, lemon juice or vinegar, salt, and maybe mustard. Commercial production scales this up with significant substitutions: soybean oil replaces olive or avocado oil (cheaper, more neutral flavor, more shelf-stable), calcium disodium EDTA is added as a chelating agent that prevents metal ions from catalyzing oxidation (extending shelf life from days to months), and "natural flavors" standardize taste across batches. Some brands add sugar and modified food starch as well. The EDTA is particularly telling; it is an industrial chelating compound also used in water treatment and medical heavy-metal detoxification, repurposed here to prevent the soybean oil from going rancid. In our analysis, mayonnaise averages a Processing Score of 6.0, which is Level 3.
How 567 mayonnaise products break down
Share of products at each processing level, in our analysis.
Mayonnaise brand comparison
From least to most processed in our database.
How to read a mayonnaise label
- 1
Homemade mayo needs just: egg yolk, oil, acid (lemon or vinegar), salt; 4 ingredients
- 2
EDTA (calcium disodium EDTA) is a chelating agent that extends shelf life from days to months
- 3
Soybean oil is used for cost and stability, not because it makes better mayo
- 4
"Light" and "low-fat" mayonnaise add water, modified food starch, and additional emulsifiers to compensate for reduced oil
Ketzal for iPhone
Got Mayonnaise At Home?
Scan yours in Ketzal to see how your exact product scores, not just the average, plus a less processed swap.
Scan It Free
Frequently asked questions
Is Hellmann's mayonnaise ultra-processed?
Hellmann's uses soybean oil, whole eggs and egg yolks, vinegar, water, salt, sugar, lemon juice, calcium disodium EDTA, and natural flavors. The EDTA and natural flavors are the main industrial additions beyond a basic mayo recipe. Each product page shows its own score.
Is Duke's mayo less processed than Hellmann's?
Duke's is slightly simpler, and it does not contain sugar, which is present in Hellmann's. Both contain EDTA and soybean oil, so on ingredients alone Duke's is only marginally less processed.
Is avocado oil mayo less processed?
Brands like Primal Kitchen use avocado oil instead of soybean oil and often skip EDTA. They typically contain fewer ingredients. The oil choice does not change the processing level, but the simpler formulation does.