How Is Mayonnaise Made Commercially?
Commercial mayonnaise is built in five controlled phases. The difference between factory mayonnaise and a kitchen whisk is control of oil dosing rate, shear, temperature and air, repeated identically across every batch.
Key Takeaways
- Commercial mayonnaise is made in five controlled phases: hydrating stabilisers, dispersing the emulsifier, dosing oil under high shear, acidifying and homogenising, then deaerating and cooling.
- Oil dosing rate is the single most important process variable. Add oil faster than the emulsion can absorb it and the batch splits or inverts.
- Vacuum emulsification (removing air during mixing) is what gives commercial mayonnaise its dense, glossy, bubble-free finish and protects shelf life.
Table of Contents
- What Is Commercial Mayonnaise Made Of
- Why Factory Mayonnaise Is Not Kitchen Mayonnaise Scaled Up
- The Industrial Mayonnaise Production Process: 5 Phases
- What Equipment Is Used to Make Mayonnaise Commercially
- How Manufacturers Keep Mayonnaise From Splitting
- Eggless and Low-Fat Mayonnaise: What Changes
- Quality Control and Shelf Life
Making mayonnaise at home is forgiving. Making it 2,000 jars at a time, with the same gloss, thickness and shelf life in every jar, is a process-engineering problem. Oil has to be introduced at the rate the emulsion can absorb it, shear has to be high enough to cut droplets fine but not so high it heats and thins the batch, and air has to be kept out or the product oxidises and foams in the filler.
This guide walks through how mayonnaise is actually produced in a factory: the five phases, the parameters that matter at each one, the equipment involved, and where batches go wrong. It is written from the process reality of building and running mayonnaise plants, not from a recipe. It is the same process our Procer Mixpro mayonnaise making machine is engineered around.
What Is Commercial Mayonnaise Made Of
Commercial mayonnaise is an oil-in-water emulsion: tiny oil droplets suspended in a continuous water phase, held apart by an emulsifier so they cannot recombine and separate. By weight, oil is the dominant ingredient. In the United States, the FDA standard of identity requires a product labelled “mayonnaise” to contain not less than 65% vegetable oil (FDA 21 CFR 169.140); most commercial formulations run 70 to 80%.
| Component | Typical share | Function |
|---|---|---|
| Vegetable oil | 65-80% | The dispersed phase: body, mouthfeel, richness |
| Water / aqueous phase | 10-20% | The continuous phase that carries everything else |
| Egg yolk (or plant protein) | 4-8% | Primary emulsifier: lecithin coats droplets and prevents coalescence |
| Vinegar / acid | 2-4% | Flavour and the safety hurdle (lowers pH) |
| Salt, sugar, mustard, spices | 1-3% | Flavour; mustard also aids emulsification |
| Stabilisers (gums, starches) | 0-2% | Viscosity and long-term stability, especially in low-fat and eggless recipes |
The emulsifier is what makes it work. In classic mayonnaise that job belongs to the lecithin in egg yolk; in eggless and vegan versions it is plant proteins (soy, pea) or starch-and-gum systems doing the same job, with more difficulty, which we will come back to.
Why Factory Mayonnaise Is Not Kitchen Mayonnaise Scaled Up
A whisk introduces oil drop by drop and relies on the cook’s judgement. A production line has to guarantee the same result every time, so three things get engineered rather than eyeballed:
- Oil dosing is metered, not poured: added at a controlled rate matched to how fast the emulsion can absorb it.
- Shear is generated by a high-shear mixer or rotor-stator homogeniser, which forces the mix through a narrow gap at high tip speed to cut oil into micron-scale droplets, far finer and more uniform than a whisk can manage.
- Air is actively removed under vacuum, because entrained air oxidises the oil (rancidity, off-colour) and disrupts accurate filling.
Miss any of those and the batch either splits, comes out thin, or fails on shelf life. That is why the phases below are defined by their parameters, not just their order.
The Industrial Mayonnaise Production Process: 5 Phases
Most commercial mayonnaise is made in a vacuum emulsifying mixer: a jacketed vessel with a bottom-mounted high-shear head, vacuum capability, and slow-speed scraped-surface agitation, often paired with an inline homogeniser for final droplet refinement. The Procer Mixpro integrates all of this into a single system. Here is what happens inside it, phase by phase.
Water Phase and Stabiliser Hydration
Water, salt, sugar and any gums or starches are combined and mixed while the high-shear head disperses the powders. Stabilisers must fully hydrate here: un-hydrated gum forms lumps that never recover later in the batch. This is where lump-free powder induction earns its keep.
Checkpoint: fully dissolved, lump-free water phase; stabilisers hydrated.
Emulsifier Dispersion
Egg yolk (pasteurised) or the plant-protein/starch emulsifier system is added into the water phase and dispersed uniformly. Getting the emulsifier evenly distributed before oil arrives is what lets the emulsion form cleanly in the next phase.
Checkpoint: homogeneous emulsifier distribution, no localised concentration.
Controlled Oil Dosing Under High Shear
This is where mayonnaise is made or lost. Oil is metered in slowly and steadily while the high-shear mixer runs continuously. Add oil faster than the interface can absorb it and the emulsion inverts or breaks. In the Procer Mixpro, the high-shear rotor-stator head cuts the incoming oil into fine droplets and drives them into the water phase; typical target droplet sizes sit in the low-micron range, because finer, more uniform droplets give a thicker, more stable product.
Checkpoint: steady viscosity build, no free oil, temperature within range.
Acidification and Homogenisation
Vinegar and remaining acid are added, both for flavour and to bring pH down to roughly 3.6 to 4.0, the range that suppresses microbial growth and is central to mayonnaise’s shelf stability. The batch is then given its final shear pass (often through an inline homogeniser) to tighten droplet size distribution and lock in texture.
Checkpoint: target pH reached; final viscosity and gloss achieved.
Deaeration, Cooling and Transfer
The finished emulsion is deaerated under vacuum to strip out air incorporated during mixing, cooled if required, then gently transferred to a buffer tank and on to filling. Deaeration is what gives commercial mayonnaise its dense, bubble-free, glossy appearance and protects it from oxidation.
Checkpoint: air-free, glossy product; accurate fill weights downstream.
| Phase | Key parameter to control | What failure looks like |
|---|---|---|
| 1. Water phase | Complete stabiliser hydration | Lumps, grainy texture |
| 2. Emulsifier | Uniform dispersion | Weak, unstable emulsion |
| 3. Oil dosing | Dosing rate vs shear | Split / inverted batch, free oil |
| 4. Acidify & homogenise | pH 3.6-4.0, final shear | Poor shelf life, thin body |
| 5. Deaerate & cool | Air removal under vacuum | Foam, dull colour, fill errors |
What Equipment Is Used to Make Mayonnaise Commercially
The core machine is a vacuum emulsifying mixer with a high-shear rotor-stator head, usually supported by an inline homogeniser, jacketed vessel for temperature control, and CIP for cleaning. Small producers may run a single batch unit; larger plants add metered oil dosing, buffer tanks and automated filling into a complete line.
The heart of the process is the high-shear emulsification system. Everything else (dosing, heating and cooling, vacuum, transfer, filling) is built around producing and protecting that emulsion. A typical build maps to the phases like this:
Powder Induction + Water Phase
High-shear mixer with powder dispersion
Emulsification + Oil Incorporation
Vacuum emulsifying mixer (rotor-stator head)
Final Droplet Refinement
Inline homogeniser: Procer’s integrated DRI (Dual Rotor Inline) homogeniser
Temperature Control
Jacketed, insulated vessel
Air Removal
Vacuum system
Hygiene
CIP (clean-in-place)
Procer builds all of this into one machine, the Procer Mixpro, rather than a set of bolted-together units. You can see the full configuration, capacities and process details on our mayonnaise making machine and production line page. The reason the machine matters as much as the recipe: the same formulation run on under-powered or poorly sequenced equipment produces an inconsistent, unstable product. Process control is the product, which is why Procer offers a recipe trial on the Mixpro before you commit to a line.
How Manufacturers Keep Mayonnaise From Splitting
The short answer: by controlling the four variables that break emulsions (oil dosing rate, shear intensity, temperature and stabiliser hydration) and holding them identical batch to batch. A split batch is almost always a process fault, not a recipe fault.
The most common cause of a broken batch is oil added faster than the emulsion can absorb it in Phase 3. Other frequent culprits:
| Symptom | Most likely cause |
|---|---|
| Emulsion splits / free oil | Oil dosed too fast; insufficient shear |
| Thin, will not thicken | Under-shear; wrong phase ratio |
| Grainy / lumpy | Incomplete stabiliser hydration (Phase 1) |
| Dull, foamy | Air not removed; no deaeration |
If your line produces inconsistent batches, the fix is usually in the equipment and sequencing, not the ingredients. The signs your emulsification line needs an upgrade go through this in detail.
Eggless and Low-Fat Mayonnaise: What Changes
Removing the egg, or removing the oil, makes emulsification harder, not easier. Egg yolk is an extremely effective natural emulsifier; take it out and a starch-and-gum or plant-protein system has to do the same job with less inherent stabilising power. That demands finer shear control and careful stabiliser hydration, because the emulsion is less forgiving of error.
Low-fat mayonnaise faces the mirror problem: with less oil, water becomes the dominant phase, and body has to come from stabilisers rather than oil volume, again shifting the burden onto precise process control. Both are entirely achievable on the same equipment, which is why a well-specified vacuum emulsifying system handles both egg and eggless mayonnaise on one platform. It is the process window that has to widen, not the machine that has to change.
Quality Control and Shelf Life
Commercial mayonnaise is checked at the points the phases define: hydration and dispersion visually, viscosity and droplet quality through and after Phase 3 to 4, and pH after acidification, the single most important safety measurement, targeting roughly 3.6 to 4.0. Combined with pasteurised egg and correct sealing, that acidity is what lets shelf-stable mayonnaise sit unrefrigerated. Deaeration protects colour and delays oxidation. Consistent fill weights depend on an air-free product from Phase 5.
None of these are one-off checks. They are the parameters that get logged every batch so the thousandth jar matches the first.
Planning a Mayonnaise Line?
Procer designs and builds high-shear vacuum emulsifying systems for mayonnaise, sauces and emulsions, for low-fat, eggless and classic high-fat recipes. Book a trial with your own recipe and see the finished product before you invest, or explore our mayonnaise making machines and production lines.
Frequently Asked Questions
See Your Recipe Made at Production Scale
Book a trial on the Procer Mixpro and see a stable, repeatable mayonnaise batch before you invest in a line.