What Is a Homogenizer?

by Patti Dees

What is a homogenizer and what does it do? These large pieces of equipment are the core of the food processing industry. However, regular maintenance is vital for consistent production and the safety of personnel and consumers alike. 

What Is a Homogenizer? 

Homogenizers are a class of machines that combine two or more distinct materials. They generate force to break down, blend, mix, emulsify, etc. Most people are familiar with home versions such as blenders and food processors. However, food processing on an industrial scale requires much larger equipment that is not only more robust but also has more advanced processing capabilities.  

Homogenizers are used to make products like mayonnaise, milk, and thousands more. For some food products, especially emulsifications like mayonnaise, the forces applied through homogenization are necessary for there to be a product at all. For others, homogenization is about delivering a consistent end product. The smaller particles produced combine more easily and are more stable at the molecular level, therefore, products are consistent over time and have a longer shelf life. 

The three most common types of homogenizers used in food processing plants are the rotor-stator mixer, the high-pressure homogenizer (HPH), and the ultrasonic homogenizer. The desired product and the form of the initial materials – solid or liquid – determine which type to use.  

The Rotor-Stator Mixer  

This is the type of homogenizer that most resembles home equipment. Rotating blades, paddles or knives turn on a shaft. The rotation creates suction, drawing materials down to the rotating parts where they are broken or chopped into smaller segments and mixed together. 

The High-Pressure Homogenizer (HPH) 

The slurry is pumped under high pressure through narrow nozzles. As the material is forced into and through the nozzles, it breaks into very small particles that mix together. Pre-processing bulky solids is required to limit nozzle clogging. 

The Ultrasonic Homogenizer  

Ultrasonic vibrations and micro-cavitation – the collapsing of small bubbles – create large shear forces. Shear forces break down the ingredient particles by sliding different particle sides in opposing directions. 

The goal of industrial-scale homogenization is the creation of a product that is consistent and easily reproduced. Brand reputation relies on the consumer experience: taste, texture, and quality. However, consumers also expect dependable supply. For this, food processing plants need reliable equipment. 

 The Role of Regular Maintenance 

All equipment, no matter the industry, benefits from regular maintenance, whether it is preventive maintenance (PM) or predictive maintenance (PdM). PM and PdM both improve efficiency and extend the life of the equipment. Additional benefits for the food processing industry are fewer process disruptions, proper sanitation, and consistent quality. 

Production Disruptions 

Production disruptions from equipment failure cost more than parts and labor. Consumers cannot buy what they cannot find, so shutting down a process line for unplanned maintenance directly hits the company’s bottom line. Fortunately, unexpected downtime due to poor maintenance practices is 100% avoidable.  

PM schedules give plant personnel control over when and if equipment needs to be shut down for required maintenance tasks. And while some surprises are unavoidable, regular maintenance helps reduce the number and severity of those disruptions. 

Quality and Consistency 

Over time parts, lines, and nozzles will suffer from buildup. Left long enough, the buildup leads to clogs or equipment jams. When parts are clogged or rotation speeds are thrown off, product quality suffers and the company’s reputation – and sales – are at stake. 

Sanitation 

Sanitation is not a common focus for most maintenance staff, but in food and drug production plants, it becomes a high priority. Corrosion and leaks within food-adjacent spaces not only jeopardize production goals, but it can also contaminate products. Sanitation requirements also impact how maintenance is completed as residues or debris from repairs can also lead to contamination or quality issues. 

Safety 

Homogenizers produce extremely powerful forces, and some processes also require high heat. Regular maintenance keeps equipment from becoming major safety hazards for plant personnel. Even if part failure is not catastrophic, the damaged parts can potentially be introduced as foreign material into the product. Aside from presenting quality issues, foreign materials can sometimes be hazardous for consumers.  

 The modern food industry relies on homogenizers. Breaking down and combining food materials on a large scale provides a more consistent and longer-lasting product. However, PM protects company investments and reputation, as well as provides safe and sanitary work areas. The professionals at Therma offer systems solutions, specialty fabrications, regular maintenance, and proactive repairs for food processing plants. 

 

Patti draws on her background as a chemical engineer to share information with readers on technology, manufacturing, and construction. 

Sources

BEE International – Food Homogenization 101: What You Need to Know

Hielscher Ultrasonics – Homogenizers – Working Principle, Use and Scale-Up

Food Research Lab – How important are Homogenizers in the FMCG Industry

Homogenizers.net – Cleaning and Maintaining a Rotor-Stator Homogenizer | Blog