Copyright © 2021 Food Research Lab. All rights reserved 1

How Important are Homogenizers in the FMCG

Industry

Dr. Nancy Agnes, Head, Technical Operations, FoodResearchLab, info@foodresearchlab.com

Keywords: Pasteurization, giant pumps, Milk

homogenization, High-pressure homogenizers,

Nano or microemulsions, thermal sterilization,

high-pressure processing, Rotor homogenizers

I. INTRODUCTION

Corona Virus pandemic has disconnected

people from their regular life, travelling, going to a

restaurant and even visiting a grocery store is a no go.

Consumers are ordering their daily bread and butter

online and it gets delivered mostly on the same day

or the next days. The person responsible for your

food to be stable for a length of time (shelf life) is

Louis Pasteur. Moreover, the method of preservation

was called Pasteurization, named after him.

Pasteurization kills the pathogens or spoilage

microorganisms present in the food and it involves

two things, temperature and time. The milk is

pasteurized in the vat at 70 ℃ for 30 minutes or at 80

℃ for 25 seconds. This is called High-Temperature

short-time pasteurization (HTST). Pasteurization

does not reduce any nutritional value of the milk,

which is a commonly asked question.

II. PASTEURIZATION

Pasteurization can also be done using water

tanks. Liquid and non-solid items can be sterilized

using a large tank filled with water. Once the package

is loaded into the tank, pressure is applied with the

help of giant pumps. The applied pressure changes

the foods cell structure which inhibits cell division

and destroys microorganisms. Using this technique,

various processed and ready to eat foods such as fruit

and vegetable juices, salsa, dressings, meat products

etc. Another advantage of using this method is that

the water tank method is capable of processing a lot

of food in every batch, making it an affordable

operation for manufacturers.

However, some studies have shown that the

pasteurization process has compromised the flavour

aspect of the food or specifically in the context of

milk. The pasteurization process does not kill all the

bacteria present in the milk, but only the harmful

bacteria. Over the years, the pasteurization process

has gained higher demand and increased usage.

Having said all this, the pasteurization process is still

better than thermal sterilization, particularly

concerning nutrient composition. These days more

food industries are starting to use high-pressure

processing which effectively removes most of the

pathogens, harmful spoilage microorganisms and

extends the shelf life significantly.

III. HOMOGENIZATION

You might have also seen milk products labelled as

HOMOGENISED milk, how different are they milk

from pasteurized milk. Milk homogenization is a

different step and usually happens after the

pasteurization. High-pressure homogenizers in food

industry will aid in delivering Nano or

microemulsions, dispersions, suspension and lipids.

Homogenization aids in breaking down the fat in

milk and stops the fat-water separation. If the

homogenization step is skipped, then fat molecules

present in milk rise to the top of the container, giving

a very bad visual appeal to the end customer.

Combining homogenization with pasteurization

allows manufacturers to effectively manage their

resources which could be served to the customers and

reduces the overall waste in the process.

Homogenization can be used for a variety of products

in the food, pharmaceutical and chemical industry;

for instance, vaccinations, anaesthetics and injections

in pharmaceutical inclinations.

IV. TYPES OF HOMOGENIZER

There are three common types of

homogenizers, which are rotor generator, high

pressure (with piston pump) and sonic disruptors in

FMCG industry. Rotor homogenizers are capable of

Copyright © 2021 Food Research Lab. All rights reserved 1

delivering large quantities of material processed

using long shafts which have angled knives at the

bottom. The knives shred the material into fine

particles and then drawn up into a stator tip and

ejected into the side. This model is capable of

handling plant and animal tissue and usually

homogenized within 60 seconds.

Liquids and semi-solids can be pasteurized with high-

pressure homogenizers which push the product

through a series of tubes. A hydraulic pump creates

enough pressure while pushing them through the

tubes and sterilizes them at 1500 bar with continuous

scale. Once this stage is complete, the product exits

through a small orifice with a drop in pressure which

forces cell rupture and tearing the product into equal

sizes which can then be equally mixed.

Sonic disruptors reduce the breakup particles with the

aid of disruptors by generating ultrasonic waves

between 18 to 50 kHz (inaudible to the human ear).

These sonic wavelengths are capable of exerting 500

atmospheres of pressure with temperatures rising to

5000 ℃. Under appropriate conditions, the pressure

waves cause microscopic bubbles to form which

grows and collapses violently after a certain point.

This implosion creates a shock wave that breaks the

cell membrane, with reduced particle size.

Copyright © 2021 Food Research Lab. All rights reserved 1

V. KEY FUNCTION OF HOMOGENIZERS

The first and foremost functionality is preventing the

separation of the top layer of cream from the rest

during new product development. This aids in

obtaining a longer shelf life and retains the finest

quality, which benefits both dairy manufacturers and

customers when milk is harder to find at a store,

especially during a pandemic.

Scientist and food manufactures are working to make

new product categories which can eliminate trans-fat,

reduced sugar and low sodium content to balance

nutrient content and to achieve customer satisfaction.

An optimal mixing protocol needs to be achieved for

each emulsion, lipids and dispersion at an economical

value. The manufacturer will develop the mixing

protocol based on the product characteristic and the

basic requirement for the product so that it is

consistent with taste, colour and appearance.

Quite a significant number of factors are considered

and attributed to foods, such as particle size and

consistency, which has an impact on food quality,

stability and shelf life. To achieve improved food

processing results, this will in turn increase the sales

of the product. For instance, a few years ago tomato

juice showed improved consistency and viscosity

because of the high shear homogenization achieved.

Secondly, this processing method also aids in food

preservation, which increases the high level of

function over traditional thermal processing methods.

Extended shelf life is achieved by high shear along

with heat kills the harmful microorganisms. This

method also destroys some nutrients from the food.

However, one alternative to this is pressure

homogenization which makes them ready to be used.

Thirdly, the quality of a food product and its

freshness is linked to food stability (molecular level).

The high-pressure shear homogenizer leads to better

chemical stability in most foods, which provides

longer periods of freshness compared to foods with

larger molecular size.

REFERENCES

1. Flores, Z., San-Martin, D., Beldarraín-Iznaga, T.,

Leiva-Vega, J., & Villalobos-Carvajal, R.

(2021). Effect of Homogenization Method and

Carvacrol Content on Microstructural and

Physical Properties of Chitosan-Based

Films. Foods, 10(1), 141.

2. Sharma, P., Gaur, V. K., Sirohi, R., Varjani, S.,

Kim, S. H., & Wong, J. W. (2021). Sustainable

processing of food waste for production of bio-

based products for circular

bioeconomy. Bioresource Technology, 124684.

3. Gazolu-Rusanova, D., Lesov, I., Tcholakova, S.,

Denkov, N., & Ahtchi, B. (2020). Food grade

nanoemulsions preparation by rotor-stator

homogenization. Food Hydrocolloids, 102,

105579.