Methods for Drying Enzyme Preparations By Eng Mustafa Ahmad Khaldoun Termanini 

1. Methods for
Drying Enzyme Preparations
Eng. Mustafa Ahmad Khaldoun Termanini

2. Proteins and enzymes for commercial use are often
driedto extendtheir shelf lives.
The dryingof enzymesis interestingto the
pharmaceutical, laundry detergent, and food processing
industriesin dryingoperationsof materialscontaining
enzymes.
The use of dehydrated enzymes for industrial
applications, especially in formulations of
pharmaceuticals and food .
Example:
Among the most used enzymes, we can mention α-
amylase. Alpha-amylase is an endoenzyme that
breaks down starch by hydrolysis to maltose
Alpha-amylase is widely used in the food and
pharmaceutical industries, laundry detergents, and in
“desizing” in textiles.

3. Methods for drying enzyme preparations
1. Spray-drying .
2. Freeze-drying (lyophilization).
3. Spray Freeze Drying (SFD).
4. Supercritical Fluid Drying (SCFD).
5. Microwave vacuum.

4. Spray-drying

5. Spray-drying
- is a process for converting a liquid into a powder by
evaporation of the solvent.
- is the most common method for drying of liquids. It is
widely used in dairy and pharmaceutical industries for
dehydration of various substances, such as: milk, whey,
antibiotics, vitamins, and enzymes.
Spray drying is a common method for producing powder
from a liquid. During the process, creating a spray of fine
droplets. The solvent quickly evaporates under these
conditions, forming dried particles. These particles are
then separated, by means of a cyclone, into a collection
container attached to the unit .

6. Spray-drying
ADVANTAGES OF SPRAY DRYING:
- Ability to quickly produce a dry powdered and
control the particle size distribution.
- More economically viable and cost-effective as it
can process larger volumes and operate at
higher energy efficiency.
- very widely applied, technical method used to
dry aqueous or organic solutions, emulsions in
industrial chemistry, and the food industry. Dry
milk powder, detergents, and dyes.

7. Spray-drying
Disadvantages OF SPRAY DRYING:
The spray drying process is more prone to damaging heat-sensitive components such
as enzymes and probiotic bacteria.
The long period of material exposure to high temperatures caused a partial activity
loss.

8. Freeze-drying
(lyophilization)

9. - is a method of preservation of food and biological
materials (enzymes, proteins, vitamins, etc.),
floral products, drugs, and whole animals.
- The material is placed on trays in a refrigerated
vacuum chamber, and heat is carefully applied by
conduction. As a result, any water in the material
is changed directly from ice to water vapor
without first changing into water.
- water is removed from the material by
sublimation while the material is still frozen.
- The frozen material is cooled to approximately -
29 °C. Freeze-drying requires pressures lower
than 5.33 bar and long drying times.
Freeze-drying (lyophilization)

10. Freeze-drying (lyophilization)
STAGES OF ENZYME LYOPHILIZATION:
(a) Initial freezing
Freezing involves the formation of ice nuclei. Depending
upon many factors, especially the cooling rate.
(b) Primary drying
This is the stage at which ice separated from the solute
phase is removed by sublimation.
(c) Secondary drying
This stage begins after all the frozen water has sublimed
and thus, can be facilitated by increasing the product
temperature.

11. Freeze-drying (lyophilization)
ADVANTAGES OF LYOPHILIZATION:
- The process of freeze-drying is recommended for the
drying of thermolabile enzymes or processes that
require the use of dehydrated enzyme with high
enzymatic activity, whose product is of high added
value.
- The most common drying method for therapeutic
proteins which has been used for many therapeutic
proteins.
- This procedure is believed to be effective to maintain
the biological activities of the material over a long
period of time.

12. DISADVANTAGES OF LYOPHILIZATION:
The freeze-drying process, the processing time and the high energy consumption can be considered
as limiting factors when choosing a technique.
Freeze-drying requires a great consumption of energy, which increases the commercial value of
dehydrated products, and a relatively long processing time.
Stabilizers can protect proteins during freezing (cryoprotectants) and lyophilization
(lyoprotectants) through water replacement and hydrogen bond formation such as glycerol,
sucrose, trehalose, and dextran.
Freeze-drying (lyophilization)

13. Spray Freeze Drying (SFD)
- is the combination of traditional Spray-drying and
Freeze-drying processes.
- involves the atomization of protein solution via a nozzle
at extremely low temperatures and has potential
applications for thermo-labile active pharmaceutical
ingredients.
- Spray Freeze Drying is a method for preparing lyophilized
protein powders with spherical microparticles.
Three phases of SFD process: atomization, fast freezing, and
drying by ice sublimation.
Types of spray freeze drying methods:
Atmospheric freezing, spray freezing with compressed
carbon dioxide, spray freezing into a vapor over a cryogenic
liquid, and spray freezing.

14. Supercritical Fluid Drying (SCFD)
- also known as critical point drying, is a process to
remove liquid in a precise and controlled way. It is
useful in the production of microelectromechanical
systems (MEMS), the drying of spices, the production
of aerogel, the decaffeination of coffee, and in the
preparation of biological specimens for scanning
electron microscopy.
- is an attractive alternative drying method because
dehydration can be rapidly accomplished in the
absence of extreme temperatures.
- may produce large amounts of dried
biopharmaceuticals with adjustable particle sizes and
morphology.

15. Microwave vacuum
- In vacuum drying, the removal of moisture
from food and bioproducts occurs under low
pressure.
- The low pressure and fast mass transfer
conferred by the vacuum incorporated with
rapid energy transfer by microwave heating
generates very rapidly, low-temperature drying
and thus has the potential to improve energy
efficiency and product quality.
- drying under a pulsed microwave vacuum is
suitable for the drying of temperature-sensitive
products such as enzymes and proteins. This
method generally results in lower energy costs
and better product quality.

16. - The major Advantages of microwave drying
are higher drying rate, energy savings, and
uniform temperature distribution, which
result in better product quality.
- an alternative method of drying to obtain
products of acceptable quality, including
foods and pharmaceutical products.
- Microwave vacuum drying combines the
advantages of both microwave heating and
vacuum drying processes.
Microwave vacuum

17. Comparison of characteristics of different drying technologies

18. References

19. References:
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20. THANK YOU
Eng. Mustafa Ahmad Khaldoun Termanini