You have learned that homogenizers are pieces of equipment that grind larger solids into the smallest possible globules, mixing them with a different substance to form a unified, crushed or liquified compound. The system of homogenization is widely relevant and useful in most industries like food and beverage, cosmetics, science and technology, and a bunch of others – industries that entail combining and emulsifying in their manufacturing process. The most common products that undergo this operation are milk, oil, water, and cream.
However, homogenization does not solely have one procedure. The materials involved to carry it out, as well as the process itself, can be different for various applications. One type can be a perfect fit for food processing but isn’t for science experimentations. That is why several types of homogenizers were made – to suit a certain kind of utilization.
Below are the chiefly used types of homogenizers under three (3) main categories which are mechanical, ultrasonic and pressure.
Three types of homogenizers fall to this category: rotor-stator homogenizers, blade type homogenizers.
What is a Rotor-Stator Homogenizer?
This type is also called colloid mill or Willems homogenizer. Works best in plant and animal tissue, it conventionally outdoes the cutting blade-type mixers. The rotor-stator homogenizer is generally used to derange microorganisms with the help of glass beads. According to Pro Scientific, cell disruption with this homogenizer demand hydraulic and mechanical shear and the process of so-called cavitation.
People would usually relate mechanical and ultrasonic categories but the only thing they share in common is the generation and usage of cavitation. What is cavitation? It is the formation of vapor cavities in a liquid stirred by a certain propeller. Once a solid element is stroked at a high speed, it is set into motion. Once movement is stimulated, cavitation is then generated. Using a rotor-stator homogenizer, the blade (rotor) acts as the stirrer of the solid sample through the liquid one at a velocity required for cavitation.
At full speed, the rotating blade (rotor) inside a static head or tube (stator) with holes draws up a cellular material into the equipment. The material is driven by a centrifugal force and prompted to plummet through the holes.
What is a Blade Type Homogenizer?
You are more familiar with this type as it is also known as a blender. It uses cutting blades which can possibly thrust in the top or bottom orientation as it rotates at a rapid speed rate. This type of apparatus can accommodate small samples to multi-gallon samples; it is less efficient than the rotor-stator type but is best used for size reduction.
Ultrasonic homogenizers are usually coined as sonicators. This type is most appropriate and effective for disintegrating cells and subcellular structures in a fluid mixture. The equipment works by releasing extreme sonic pressure waves in suspension. Through ultrasonic waves and cavitation, it disrupts cells and tissues but does not do a great job in homogenizing intact tissues.
Tiny bubbles are formed in the liquid due to streaming evoked by pressure waves. Cavitation takes place as these bubbles grow and converge to a full-bodied size, vigorously shake and then collapse. Ideally, ultrasonic homogenizers are used in science-related operations.
Various manufacturers have integrated a compressing valve with high pressure. Many high-pressure homogenizers conform to the design of a commercial machine that induces emulsions and homogenized products in the food and pharmaceutical industries. Ginhong mixers are one of them.
A heat exchanger should essentially be attached to the outlet port of pressure homogenizers because a substantial amount of heat is produced by the operation.
Through the years, high-pressure homogenizers have been used to convulse cells marked with bacteria. This method has been successful for the disruption of disparate bacteria, mycelia, and yeast – except for the ‘highly filamentous’ microorganisms.
How do high-pressure homogenizers work? By coercing suspensions through a tapered crevice or opening under a significant amount of pressure. Impingement design is present only in some types of high-pressure homogenizers. But those that possess it are more functional and powerful than those which do not.
Other factors that affect the equipment’s efficacy are pressure, temperature, the number of passes, flow rate, and valve and impingement design.
Compression, emulsion, mixing, disruption, blending, dispersion, stirring, etc. Homogenizers almost have the same objective but this can be favorably achieved through various and appropriate types, depending on the samples or content, its throughput and the system itself. This article is meant to enlighten you about the existing types of homogenizers and which best suits your cause. We hope this would help you figure out what you need.