Emulsifying Mixer Selection Guide for Mayonnaise - One Week or One Year Shelf Life

This article, based on the scientific principles and industrial practices of food emulsification, systematically analyzes the selection logic of emulsifying mixer used in mayonnaise production. The focus is on comparing the technical differences and applicable scenarios between hanger-type/single-stage emulsification pumps and three-stage emulsification systems.

I. The Emulsification Science of Mayonnaise: Why Does Equipment Determine Shelf Life?

Mayonnaise is a typical oil-in-water emulsion with a high oil content of 49.00%–73.70% and a pH value between 3.37 and 4.08. Maintaining such a high proportion of oil stably dispersed in the aqueous phase and remaining unseparated for months is a technical challenge in food engineering.

The stability of the emulsion depends on the oil droplet size. Studies show that the particle size distribution [D(4,3)] of commercially available mayonnaise is typically between 4 and 12μm. When the oil droplet size is less than 5 micrometers, Brownian motion is sufficient to overcome gravitational sedimentation, allowing the emulsion to remain stable for a long period.

This is why the choice of emulsification equipment directly determines the shelf life of mayonnaise. How finely the equipment can break down the oil droplets determines how long the product can remain stable.

II. Hanger-mounted/Single-stage Emulsifying Pumps: Suitable for Short-Term Consumption Scenarios

Firstly, let us discuss the short-term mayonnaise emulsifying mixer choices.

2.1 Equipment Features

Hanger-mounted emulsifying mixer and single-stage emulsifying pump are fundamental equipment in mayonnaise production. Their core structure is a single-stage stator-rotor system, with speeds typically ranging from 0 to 2900 rpm. 

Following is the video of the hanger type mixer for mayonnaise making for your reference:

2.2 Technical Limitations

The emulsification head design and single-stage shearing capacity of single-stage emulsification pumps(below is the single-stage pump with the tank design) are limited. It is impossible to break down the water-oil mixture to the nanoscale. While lecithin in egg yolks can form a protective film around oil droplets, the stability of this film significantly decreases when the oil droplet size exceeds 20μm.

Consequence: The emulsion is unstable, and water and oil easily separate. Mayonnaise produced using this type of equipment typically has a shelf life of only about one week.

2.3 Applicable Scenarios

This device is only suitable for usage scenarios where it will be consumed within one week:

In these scenarios, mayonnaise is consumed completely within a few days, so there is no need to consider its long-term storage stability.

III. Three-Stage Emulsifying Pump and Mixing Tank: An Industrial-Scale Long Shelf-Life Solution

When you need the mayonnaise with a long shelf lift, you need to purchase the emulsifying mixer with three-stage emulsifying system.

3.1 Technical Principle

The three-stage emulsifying pump adopts a three-stage stator-rotor series design, with stator and rotor structures of different precision sequentially equipped, and the gap is controlled between 0.2-0.3mm. The material undergoes emulsification and shearing three times.

The material undergoes three stages of progressively stronger shearing, gradually breaking the oil droplets down to an extremely fine particle size.

3.2 Equipment Configuration

3.3 Comparison

Compared to split type emulsifier mixer, SLFT series(see below picture) offer greater flexibility in design and higher working efficiency:

  ● Integrated vacuum emulsifiers can be equipped with separate water and oil tanks, adding a pretreatment step and directly improving production efficiency.

  ● The combined advanced vacuum emulsifying mixer also support customized recipe storage, allowing users to preset process parameters for different consistencies and flavors.

IV. Core Comparison of the Two Schemes

V. Conclusion

The selection of mayonnaise emulsifying mixer is essentially a trade-off between shelf life requirements and investment costs.

1)Short-term consumption scenarios (within one week): Hanging or single-stage emulsification pumps are sufficient, with low investment and quick results.

2)Industrial-scale long-shelf-life scenarios (six months to one year): A three-stage emulsification system is essential.

  ● Small to medium scale: Split-type three-stage emulsification pump + mixing tank

  ● Large-scale production: Integrated three-stage vacuum emulsifier

Core principle: Do not attempt to produce long-shelf-life mayonnaise with single-stage equipment. The saved equipment costs are far outweighed by the losses from product stratification and returns. The fineness and uniformity of emulsification have a significant impact on the product's taste, shelf life, and production stability. Choosing the right emulsifying mixer for mayonnaise is the first step to the success of mayonnaise products.