Stationary. Ideal for Small to Large Batches.

Applications:

• Incorporation of CBD into foods
• Dispersion of Filter Aid Powders
• Hydration of Xanthan/Guar Gum
• Preparation of Gelatin Solutions
  
• Production of Cream Liqueurs

Portable. Ideal for Small Batches

Applications:

• Blending Raw Fruits or Vegetables with Water
• Hydration of Xanthan/Guar Gum
• Dispersion of Filter Aid Powders
• Dispersion of Starches, Alginates, etc. in Fruit Juices
• Preparation of Gelatin Solutions
  
• Production of Cream Liqueurs

Portable. Ideal for Medium to Large Batches

Applications:

• Preparation of Sugar Syrups
• Preparation of Gelatin Solutions
  
• Production of Cream Liqueurs
• Blending Raw Fruits or Vegetables with Water

Emulsions are found in many food products like low fat spreads, salad dressing, soft cheese, etc.

What Is Emulsion?

Oil and water don’t mix.

Emulsions are a dispersion system composed of two incompatible liquids, that is, a mixture of one liquid in the form of small droplets dispersed into another liquid. Emulsions are ordinarily composed of water and oil and it is customary to refer to organic liquids that are insoluble in water as oil phase.

The commercial preparation of most emulsions involves the application of :

• Mechanical device (HIGH SHEAR MIXER or colloidal mill)
• Chemical emulsifier (Emulsifiers or surfactant)

WHAT IS A HIGH SHEAR MIXER?

Rotor/Stator mixers, also called high shear mixers, are comprised of a rotor turning at high speeds within a stationary stator.

The product is suctioned through the inlet and the rotor pushes it to the stator. The mixer creates mechanical and hydraulic shear by continuously drawing product into the rotor and expelling them radially through the openings in the stator.

It is not “magic”, an emulsifier is essentially required to achieve desired stability.

Emulsion types:

Two general types of emulsions are possible:

• O/W (oil-in-water)
• W/O (water-in-oil)

• All emulsions, whether w/o or o/w, require an emulsifier to assist with stability.
• Oil in water (O/W) emulsions typically require more than one emulsifier and water in oil (W/O) emulsions only require one emulsifier.

WHAT IS DROPLET SIZE DISTRIBUTION (DSD)?

In practice, most commercial emulsions have particles ranging from about 0.2 µm to 100 µm in diameter.

• The most obvious physical characteristic of an emulsion is the size of the oil droplets.
• Droplet size distribution affect taste, smell and visual appearance, as well as shelf life and spread behavior.
• The mechanical/hydraulic action must be capable to produce a dispersed phase with a droplet size small enough to result in a finished product with the desired properties.
• The mechanical/hydraulic action breaks oil down into teeny-tiny droplets that can remain suspended in the water.
• Not all the oil droplets are the same size. A given emulsion cannot be characterized by stating a single particle size. Instead, a mean particle size, plus information on the particle size distribution, must be determined.

Can I get a homogenization with a high shear mixer?

Yes.

Homogenization is the process of making a product completely uniform in terms of particle size (Droplet size). Also, homogenization is the process of emulsifying two immiscible liquids or uniformly dispersing solid particles throughout a liquid.

The high shear (rotor/stator) is designed to reduce particle sizes based on shear forces and the results depend on the degree of particle size reduction required for your application. 

Homogenization misconceptions:

Sometimes when the people think of “homogenization” they think of milk homogenization.

Milk homogenization requires a droplet size of 0.2 – 2 microns. To achieve that usually you will need a “high pressure homogenizer”.

These is a powerful machine that uses a piston pump to force the product through a very small adjustable aperture at high pressure to reduce the oil particle size down to sub-micron size.  

What is a colloid mill?

A colloid mill is a machine used in the disintegration of solid particles or droplet size of a liquid present in suspension or emulsion.

Colloid mills work on the rotor-stator principle. The equipment breaks down materials by forming dispersion of materials in a liquid. Shearing takes place in a narrow gap between a static cone (the stator) and a rapidly rotating cone (the rotor).

The range of droplet size is 1- 8 microns. 

Equipment comparative chart

One stage high shear inline mixer

Tank turnover

The amount of mixing required to achieve equilibrium mixing is measured in tank turnover – the number of times the volume of material must pass through the high-shear zone.

Example:

Flow rate: 100 GPM

Batch size: 100 Gallons

Tank turnover equilibrium: 5 pass 

Mixing time: 5 minutes

There are three types of liquid dispersions: true solution, colloidal dispersion, and suspension.

TRUE SOLUTIONS: (< 1 nm)

True solutions are ions or small molecules (such as monosaccharides and salts) that are less than one nanometer in diameter dispersed in liquid. They are invisible under any microscope and can pass through most membranes. They are very stable, and the solutions are transparent.

COLLOIDAL DISPERSION: (1 nm to 1000 nm)

Colloids are formed when one substance (liquid, solid or gas) is dispersed through another, but does not combine to form a solution.

Emulsions are an example of colloids composed of tiny particles suspended in another immiscible (unmixable) material. Strictly speaking, the term colloidal refers to particles with at least one dimension ranging from 1 nm to 1 µm.

Examples: whipped cream, mayonnaise, milk, butter, gelatin, jelly, muddy water, plaster, colored glass, etc. 

SUSPENSIONS: (> 1000 nm)

Simply defined as a heterogeneous mixture of two substances in which one is dispersed into the other, suspensions involve particles larger than those found in solutions, typically over 1,000 nm (1 micron).

Common dispersions widely used in manufacture of food products:

powder dispersion:

Powder dispersion is the mixing process that involves the introduction of dry material into water or other liquids. Can be classified as easy to disperse and difficult to disperse.

Some examples:

Difficult-to-disperse powders:

• Xanthan gum (common in salad dressings and sauces). It helps to prevent oil separation by stabilizing the emulsion, although it is not an emulsifier. Xanthan gum also helps suspend solid particles. Xanthan gum helps create the desired texture in many ice creams.
• Pectin improves the taste and texture of yogurt by serving as a stabilizer and gelling agent and increasing the shelf life of yogurt.
• Carboxymethyl cellulose plays an emulsifying stabilizing role in drinks containing fat and protein.

easy-to-disperse powders:

Generally, do not present lumping problems and require moderate shear.

• Granulated sugar
• Milk powder

Liquid dispersion:

Dispersion of two immiscible liquids is called emulsification (Milk is a commonly cited example of an emulsion)

“The use of the right mixing equipment is key to not only prevent lumping, but also to increase productivity, enhance product quality and reduce energy costs”.

WHAT IS A HIGH SHEAR MIXER?

Rotor/Stator mixers, also called high shear mixers, are comprised of a rotor turning at high speeds within a stationary stator.

The product is suctioned through the inlet and the rotor pushes it to the stator. The mixer creates mechanical and hydraulic shear by continuously drawing product into the rotor and expelling them radially through the openings in the stator.

Why do some powder form lumps when added to water?

One problem arises when dispersing difficult powders. The powders float and begin to hydrate nearly as soon as they are added to water, this can result in the formation of sticky masses “fisheyes” or lumps with a hydrated skin and dry core, where the water couldn't penetrate.

Portable. Ideal for Small Batches

Applications: