Post on 14-May-2021
description
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.